assembly-tuning-use-an-apertureless-near-field-infrared-microscope

Assembly, Tuning and Use of an Apertureless Near Field Infrared Microscope for Protein Imaging

This paper aims to instruct the reader in the assembly and operation of an infrared near-field microscope for imaging beyond the diffraction limit.  The ...

cooling-rate-dependent-ellipsometry-measurements-to-determine

Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films

This report aims to fully describe the experimental technique of using ellipsometry for cooling rate dependent Tg (CR-Tg) experiments. These measurements ...

University of Wisconsin

University of Pennsylvania

&#x6211;&#x4EEC;&#x5DF2;&#x7528;&#x4E8E;&#x53EF;&#x53D8;&#x51B7;&#x5374;&#x7387;&#x692D;&#x504F;&#x6D4B;&#x91CF;&#x63A2;&#x6D4B;&#x652F;&#x6301;&#x805A;&#x82EF;&#x4E59;&#x70EF;&#x8584;&#x819C;&#x4E2D;&#x6162;&#x7684;&#x52A8;&#x6001;&#x3002;&#x6700;&#x6162;&#x51B7;&#x5374;&#x7387; &#xFF08;&#x5927;&#x7EA6; 1 K/min) &#x6D4B;&#x5F97;&#x7684; Tg &#x503C;&#x51CF;&#x5C11;&#x5230;&#x4F4E;&#x4E8E; 6 nm &#x7535;&#x5F71;&#x4E0E; 341 K &#x6D4B;&#x91CF; Tg &#x7684;&#x5927;&#x5BB9;&#x91CF;&#x503C;&#x3002;&#x7531;&#x4E8E;&#x51B7;&#x5374;&#x901F;&#x5EA6;&#x589E;&#x52A0; Tg &#x51CF;&#x5C11;&#x53D8;&#x5C0F;&#x76F4;&#x81F3;&#x5728;&#x51B7;&#x5374;&#x7387; &gt; 90 K/min &#x6709;&#x53EA;&#x6709;&#x8F7B;&#x5FAE;&#x7684;&#x4F9D;&#x8D56;&#x4E8E;&#x819C;&#x7684;&#x539A;&#x5EA6; Tg &#x503C;&#x7684;&#x8BC1;&#x636E;&#x3002;&#x901A;&#x8FC7;&#x4E0E;&#x51B7;&#x5374;&#x901F;&#x5EA6;&#x6709;&#x5173;&#x7684;&#x5F1B;&#x8C6B;&#x65F6;&#x95F4;&#xFF0C;&#x6211;&#x4EEC;&#x8868;&#x660E;&#xFF0C;&#x653E;&#x5BBD;&#x8584;&#x819C;&#x52A8;&#x529B;&#x5B66;&#x4F3C;&#x4E4E;&#x6210;&#x4E3A;&#x963F;&#x4F26;&#x5C3C;&#x4E4C;&#x65AF;&#x4E0E;&#x51CF;&#x5C0F;&#x8584;&#x819C;&#x539A;&#x5EA6;&#x7684;&#x6D3B;&#x5316;&#x80FD;&#x3002;&#x6211;&#x4EEC;&#x8BA8;&#x8BBA;&#x8FD9;&#x65B9;&#x9762;&#x53EF;&#x80FD;&#x8FDE;&#x63A5;&#x5230;&#x957F;&#x5EA6;&#x89C4;&#x6A21;&#x4E3A;&#x5408;&#x4F5C;&#x7684;&#x8BAE;&#x6848;&#x3002;&#x6700;&#x540E;&#xFF0C;&#x7ED3;&#x679C;&#x53EF;&#x4EE5;&#x7528;&#x4E8E;&#x89E3;&#x51B3;&#x5927;&#x91CF;&#x7684;&#x6587;&#x732E;&#x4E2D;&#x7684;&#x7A81;&#x51FA;&#x77DB;&#x76FE;&#x62A5;&#x9053;&#x3002;

&#x63A2;&#x8BA8;&#x6162;&#x52A8;&#x6001;&#x652F;&#x6301;&#x8584;&#x7684;&#x805A;&#x5408;&#x7269;&#x8584;&#x819C;&#x3002;

We have used variable cooling rate ellipsometric measurements to probe the slow dynamics in thin supported polystyrene films. For the slowest cooling rates (approximately 1 K/min) the measured Tg values are reduced below the bulk value with the measured Tg of 341 K for a 6 nm film. As the cooling rate is increased the Tg reductions become smaller until at cooling rates >90 K/min there is only slight evidence for a film-thickness-dependent Tg value. By relating the cooling rate to a relaxation time, we show that the relaxation dynamics of the thin films appears to become Arrhenius with an activation energy that decreases with decreasing film thickness. We discuss this in terms of a possible connection to a length scale for cooperative motion. Finally, the results can be used to resolve a number of outstanding contradictory reports in the literature.

Probing slow dynamics in supported thin polymer films.

Nous avons utilis&eacute; la variable refroidissement mesures ellipsom&eacute;trique de vitesse pour sonder la dynamique lente en couches minces de polystyr&egrave;ne pris en charge. Pour le taux de refroidissement plus lent (environ 1 K/min), les valeurs mesur&eacute;es de la Tg diminuent au-dessous de la valeur en vrac avec le Tg mesur&eacute;e de 341 K pour un film de 6 nm. Lorsque le taux de refroidissement est accru les r&eacute;ductions Tg sont amenuisent jusqu&#39;au taux de refroidissement &gt; 90 K/min il y a seulement une l&eacute;g&egrave;re preuve pour une valeur de Tg &eacute;paisseur d&eacute;pendante-film. Concernant le taux de refroidissement d&#39;un temps de relaxation, nous montrons que la relaxation dynamique des films minces semble devenir Arrhenius avec une &eacute;nergie d&#39;activation qui d&eacute;cro&icirc;t avec la diminution d&#39;&eacute;paisseur du film. Nous discutons de cela en ce qui concerne une connexion possible &agrave; une &eacute;chelle de longueur pour le mouvement coop&eacute;ratif. Enfin, les r&eacute;sultats peuvent servir &agrave; r&eacute;soudre un certain nombre de rapports contradictoires dans la litt&eacute;rature.

Palpage dynamique lente dans des films polym&egrave;res minces pris en charge.

Probing langsame Dynamik in d&#xFC;nnen Polymerschichten unterst&#xFC;tzt.

Abbiamo utilizzato misure ellipsometric tasso variabile di raffreddamento per sondare la dinamica lenta in pellicole sottili di polistirene supportati. Per le tariffe pi&ugrave; lento raffreddamento (circa 1 K/min) i valori misurati di Tg sono ridotti sotto il valore di massa con il Tg misurato di K 341 per un film 6 nm. Come viene aumentata la velocit&agrave; di raffreddamento le riduzioni Tg diventano pi&ugrave; piccole fino a raffreddamento tariffe &amp;gt; 90 K/min c&#39;&egrave; solo lieve evidenza per un valore di Tg film-spessore-dipendente. Mettendo in relazione la velocit&agrave; di raffreddamento per un momento di relax, ci mostrano che il rilassamento dinamica delle pellicole sottili sembra diventare Arrhenius con un&#39;energia di attivazione diminuisce con la diminuzione dello spessore del film. Discutiamo di questo in termini di una possibile connessione con una scala di lunghezza per il movimento cooperativo. Infine, i risultati possono essere utilizzati per risolvere una serie di notizie contraddittorie eccezionale nella letteratura.

Sondaggio dinamica lenta in film polimerici sottili supportati.

&#x30B5;&#x30DD;&#x30FC;&#x30C8;&#x3055;&#x308C;&#x3066;&#x3044;&#x308B;&#x30DD;&#x30EA;&#x30B9;&#x30C1;&#x30EC;&#x30F3;&#x8584;&#x819C;&#x306B;&#x304A;&#x3051;&#x308B;&#x9045;&#x3044;&#x30C0;&#x30A4;&#x30CA;&#x30DF;&#x30AF;&#x30B9;&#x3092;&#x30D7;&#x30ED;&#x30FC;&#x30D6;&#x306B;&#x53EF;&#x5909;&#x51B7;&#x5374;&#x7387;&#x30A8;&#x30EA;&#x30D7;&#x30BD;&#x30E1;&#x30C8;&#x30EA;&#x30FC;&#x6E2C;&#x5B9A;&#x3092;&#x4F7F;&#x3044;&#x307E;&#x3057;&#x305F;&#x3002;&#x6700;&#x3082;&#x9045;&#x3044;&#x51B7;&#x5374;&#x7387; &#xFF08;&#x7D04; 1 K/&#x5206;&#xFF09; &#x306E;&#x6E2C;&#x5B9A;&#x306E; Tg &#x5024; 341 K &#x306E;&#x6E2C;&#x5B9A;&#x306E; Tg &#x3068;&#x30D0;&#x30EB;&#x30AF;&#x5024; 6 nm &#x30D5;&#x30A3;&#x30EB;&#x30E0;&#x306E;&#x4E0B;&#x306B;&#x524A;&#x6E1B;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002;&#x51B7;&#x5374;&#x901F;&#x5EA6;&#x304C;&#x5897;&#x52A0;&#x3059;&#x308B;&#x3068; Tg &#x306E;&#x524A;&#x6E1B;&#x306F;&#x51B7;&#x5374;&#x901F;&#x5EA6;&#x3067;&#x5C0F;&#x3055;&#x304F;&#x307E;&#x3067;&#x306A;&#x308B;&#x76EE; 90 K/&#x5206;&#x304C;&#x3042;&#x308B;&#x306E;&#x307F;&#x308F;&#x305A;&#x304B;&#x306A;&#x8A3C;&#x62E0;&#x306E;&#x819C;&#x539A;&#x4F9D;&#x5B58; Tg &#x5024;&#x3002;&#x51B7;&#x5374;&#x901F;&#x5EA6;&#x3092;&#x7DE9;&#x548C;&#x6642;&#x9593;&#x306B;&#x95A2;&#x3059;&#x308B;&#x3053;&#x3068;&#x7DE9;&#x548C;&#x3092;&#x793A;&#x3059;&#x8584;&#x819C;&#x306E;&#x30C0;&#x30A4;&#x30CA;&#x30DF;&#x30AF;&#x30B9;&#x306F;&#x3001;&#x30A2;&#x30EC;&#x30CB;&#x30A6;&#x30B9;&#x819C;&#x539A;&#x306E;&#x6E1B;&#x5C11;&#x3068;&#x3068;&#x3082;&#x306B;&#x4F4E;&#x4E0B;&#x6D3B;&#x6027;&#x5316;&#x30A8;&#x30CD;&#x30EB;&#x30AE;&#x30FC;&#x3068;&#x306A;&#x3063;&#x3066;&#x8868;&#x793A;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002;&#x6211;&#x3005; &#x306F;&#x9577;&#x3055;&#x30B9;&#x30B1;&#x30FC;&#x30EB;&#x5354;&#x8ABF;&#x904B;&#x52D5;&#x306E;&#x305F;&#x3081;&#x306B;&#x53EF;&#x80FD;&#x306A;&#x63A5;&#x7D9A;&#x306E;&#x9762;&#x3067;&#x3053;&#x308C;&#x3092;&#x8A71;&#x3057;&#x5408;&#x3044;&#x307E;&#x3059;&#x3002;&#x6700;&#x5F8C;&#x306B;&#x3001;&#x7D50;&#x679C;&#x306F;&#x9855;&#x8457;&#x306A;&#x77DB;&#x76FE;&#x306E;&#x30EC;&#x30DD;&#x30FC;&#x30C8;&#x3001;&#x6587;&#x5B66;&#x306E;&#x6570;&#x3092;&#x89E3;&#x6C7A;&#x3059;&#x308B;&#x3092;&#x4F7F;&#x7528;&#x3067;&#x304D;&#x307E;&#x3059;&#x3002;

&#x30B5;&#x30DD;&#x30FC;&#x30C8;&#x3055;&#x308C;&#x3066;&#x3044;&#x308B;&#x9AD8;&#x5206;&#x5B50;&#x8584;&#x819C;&#x306B;&#x304A;&#x3051;&#x308B;&#x30B9;&#x30ED;&#x30FC;&#x30C0;&#x30A4;&#x30CA;&#x3092;&#x30D7;&#x30ED;&#x30FC;&#x30D3;&#x30F3;&#x30B0;&#x3002;

&#xC9C0;&#xC6D0; &#xB418;&#xB294; &#xD3F4;&#xB9AC;&#xC2A4; &#xD2F0; &#xB80C; &#xBC15;&#xB9C9;&#xC758; &#xB290;&#xB9B0; &#xC5ED;&#xD559; &#xC870;&#xC0AC;&#xB97C; &#xB0C9;&#xAC01; &#xC18D;&#xB3C4; ellipsometric &#xCE21;&#xC815; &#xBCC0;&#xC218; &#xC0AC;&#xC6A9;. &#xAC00;&#xC7A5; &#xB290;&#xB9B0; &#xB0C9;&#xAC01; &#xC18D;&#xB3C4; (&#xC57D; 1 K/min)&#xC5D0; &#xB300; &#xD55C; &#xCE21;&#xC815;&#xB41C; Tg &#xAC12; 6 nm &#xD544;&#xB984; 341 K&#xC758; &#xCE21;&#xC815; &#xB41C; Tg&#xC640; &#xB300;&#xB7C9; &#xAC12; &#xC544;&#xB798; &#xC904;&#xC77C; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;. &#xB0C9;&#xAC01; &#xC18D;&#xB3C4;&#xAC00; &#xC99D;&#xAC00; Tg &#xAC10;&#xC18C; &#xB420; &#xB0C9;&#xAC01; &#xC18D;&#xB3C4;&#xC5D0; &#xC791;&#xC740; &amp;gt; 90 K/min&#xAC00;&#xB294; &#xD544;&#xB984; &#xB450;&#xAED8; &#xC885;&#xC18D; Tg &#xAC12;&#xC5D0; &#xB300; &#xD55C; &#xC99D;&#xAC70;&#xC5D0;&#xB9CC; &#xC57D;&#xAC04;&#xC758;. &#xC6B0;&#xB9AC;&#xAC00; &#xBCF4;&#xC5EC;&#xC8FC;&#xB294; &#xD734;&#xC2DD; &#xD734;&#xC2DD; &#xC2DC;&#xAC04;, &#xB0C9;&#xAC01; &#xC18D;&#xB3C4; &#xAD00;&#xB828; &#xD558; &#xC5EC; &#xC5ED;&#xD559;&#xC740; &#xBC15;&#xB9C9;&#xC758; &#xD65C;&#xC131;&#xD654; &#xC5D0;&#xB108;&#xC9C0;&#xB294; &#xAC10;&#xC18C; &#xD558;&#xB294; &#xB9C9; &#xB450;&#xAED8; &#xAC10;&#xC18C;&#xC640; Arrhenius &#xB420; &#xB098;&#xD0C0;&#xB0A9;&#xB2C8;&#xB2E4;. &#xC6B0;&#xB9AC; &#xD611;&#xB825; &#xBAA8;&#xC158;&#xC758; &#xAE38;&#xC774; &#xADDC;&#xBAA8;&#xC5D0; &#xAC00;&#xB2A5;&#xD55C; &#xC5F0;&#xACB0;&#xC758; &#xAD00;&#xC810;&#xC5D0;&#xC11C;&#xC774; &#xBB38;&#xC81C;&#xB97C; &#xB17C;&#xC758; &#xD569;&#xB2C8;&#xB2E4;. &#xB9C8;&#xC9C0;&#xB9C9;&#xC73C;&#xB85C;, &#xACB0;&#xACFC; &#xBB38;&#xD559;&#xC5D0; &#xB6F0;&#xC5B4;&#xB09C; &#xBAA8;&#xC21C; &#xB41C; &#xBCF4;&#xACE0;&#xC11C; &#xC218;&#xB97C; &#xD574;&#xACB0; &#xD558;&#xAE30; &#xC704;&#xD574; &#xC0AC;&#xC6A9;&#xD560; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;.

&#xC9C0;&#xC6D0; &#xB418;&#xB294; &#xC587;&#xC740; &#xD3F4;&#xB9AC;&#xBA38; &#xD544;&#xB984;&#xC5D0; &#xB290;&#xB9B0; &#xC5ED;&#xD559; &#xC870;&#xC0AC;.

Hemos utilizado las medidas Elipsom&eacute;trica de tasa de refrigeraci&oacute;n variable para sondear la din&aacute;mica lenta en pel&iacute;culas delgadas de poliestireno compatibles. Para las tarifas m&aacute;s lento enfriamiento (aproximadamente 1 K/min), los valores medidos de Tg se reducen por debajo del valor de a granel con el Tg medido de 341 K para una pel&iacute;cula de 6 nm. Medida que se aumenta la velocidad de enfriamiento las reducciones de Tg se hacen m&aacute;s peque&ntilde;as hasta en las tasas de enfriamiento &gt; 90 K/min hay s&oacute;lo leve evidencia de un valor de Tg de pel&iacute;cula-grueso-dependiente. Al relacionar la velocidad de enfriamiento para un tiempo de relajaci&oacute;n, demostramos que la relajaci&oacute;n din&aacute;mica de las pel&iacute;culas delgadas parece ser Arrhenius con una energ&iacute;a de activaci&oacute;n que disminuye con la disminuci&oacute;n de espesor del film. Discutimos esto en t&eacute;rminos de una posible conexi&oacute;n con una escala de longitud para el movimiento cooperativo. Finalmente, los resultados pueden utilizarse para resolver una serie de extraordinarios informes contradictorios en la literatura.

Sondear din&aacute;mica lenta en pel&iacute;culas de pol&iacute;mero delgada compatibles.

&#x4F7F;&#x7528; apertureless &#x7684;&#x8FD1;&#x573A;&#x7EA2;&#x5916;&#x663E;&#x5FAE;&#x955C;&#xFF0C;poly(methyl methacrylate)-b-&#x805A;&#x82EF;&#x4E59;&#x70EF; (PS-b-&#x805A;&#x7532;&#x57FA;&#x4E19;&#x70EF;&#x9178;&#x7532;&#x916F;) &#x5D4C;&#x6BB5;&#x5171;&#x805A;&#x7269;&#x8584;&#x819C;&#x7684;&#x8868;&#x9762;&#x7EB3;&#x7C73;&#x5316;&#x5B66;&#x6210;&#x5206;&#x53D8;&#x5316;&#x5BF9;&#x6B64;&#x8FDB;&#x884C;&#x8C03;&#x67E5;&#x3002;&#x8C03;&#x5236;&#x7684;&#x539F;&#x5B50;&#x529B;&#x663E;&#x5FAE;&#x955C; &#xFF08;AFM&#xFF09; &#x63D0;&#x793A;&#x7684;&#x4E8B;&#x4EF6;&#x7EA2;&#x5916;&#x7EBF;&#x5149;&#x675F;&#x6563;&#x5C04;&#x63A2;&#x6D4B;&#x5728;&#x63D0;&#x793A;&#x632F;&#x8361;&#x9891;&#x7387;&#x4F7F;&#x7528;&#x96F6;&#x5DEE;&#x68C0;&#x6D4B;&#x548C;&#x89E3;&#x8C03;&#x3002;&#x7EA2;&#x5916;&#x8870;&#x51CF;&#x589E;&#x52A0;&#x5BCC;&#x542B;&#x805A;&#x7532;&#x57FA;&#x4E19;&#x70EF;&#x9178;&#x7532;&#x916F;&#x7684;&#x57DF;&#x4E2D;&#x89C2;&#x5BDF;&#x5230;&#x7B26;&#x5408;&#x6563;&#x88C5;&#x5438;&#x6536;&#x8C31;&#x7684;&#x6CE2;&#x6570;&#x4F9D;&#x8D56;&#x3002;&#x7ED3;&#x679C;&#x8868;&#x660E;&#xFF0C;&#x5373;&#x4F7F;&#x8FD1;&#x573A;&#x56FE;&#x50CF;&#x4E2D;&#xFF0C;&#x53EF;&#x4EE5;&#x770B;&#x5230;&#x5C0F;&#x5730;&#x5F62;&#x5F15;&#x8D77;&#x7684;&#x4F2A;&#x5F71;&#xFF0C;&#x6E05;&#x695A;&#x68C0;&#x6D4B;&#x6837;&#x54C1;&#x7684;&#x5316;&#x5B66;&#x7B7E;&#x540D;&#x3002;

&#x5316;&#x5B66;&#x6210;&#x50CF;&#x8868;&#x9762;&#x7684;&#x81EA;&#x7EC4;&#x88C5;&#x4F7F;&#x7528; apertureless &#x7684;&#x805A;&#x82EF;&#x4E59;&#x70EF;-b-poly(methyl methacrylate) &#x5D4C;&#x6BB5;&#x5171;&#x805A;&#x7269;&#x8584;&#x819C;&#x8FD1;&#x573A;&#x7EA2;&#x5916;&#x663E;&#x5FAE;&#x955C;&#x3002;

The nanoscale chemical composition variations of the surfaces of thin films of polystyrene- b-poly(methyl methacrylate) (PS- b-PMMA) diblock copolymers are investigated using apertureless near-field IR microscopy. The scattering of the incident infrared beam from a modulated atomic force microscopy (AFM) tip is probed using homodyne detection and demodulation at the tip oscillation frequency. An increase in the IR attenuation is observed in the PMMA-rich domains with a wavenumber dependence that is consistent with the bulk absorption spectrum. The results indicate that even though a small topography-induced artifact can be observed in the near-field images, the chemical signature of the sample is detected clearly.

Chemical imaging of the surface of self-assembled polystyrene-b-poly(methyl methacrylate) diblock copolymer films using apertureless near-field IR microscopy.

Les variations de composition chimique de l&#x26;#39;&#xE9;chelle nanom&#xE9;trique les surfaces de films minces de polystyr&#xE8;ne-b-poly (m&#xE9;thacrylate de m&#xE9;thyle) (PS-b-PMMA) copolym&#xE8;res diblocs sont interpr&#xE9;t&#xE9;es par ouverture pour microscopie en champ proche infrarouge. La dispersion du faisceau infrarouge incident &#xE0; partir d&#x26;#39;un microscope &#xE0; force atomique modul&#xE9; (AFM) est sond&#xE9; embout utilisant une d&#xE9;tection homodyne et de d&#xE9;modulation &#xE0; la fr&#xE9;quence d&#x26;#39;oscillation la pointe. Une augmentation de l&#x26;#39;att&#xE9;nuation IR est observ&#xE9;e dans les domaines riches en PMMA avec une d&#xE9;pendance nombre d&#x26;#39;onde qui est compatible avec le spectre d&#x26;#39;absorption en vrac. Les r&#xE9;sultats indiquent que m&#xEA;me si une petite topographie induite par artefact peut &#xEA;tre observ&#xE9; dans les images en champ proche, la signature chimique de l&#x26;#39;&#xE9;chantillon est d&#xE9;tect&#xE9;e clairement.

Imagerie chimique de la surface de l&#x26;#39;auto-assembl&#xE9;s en polystyr&#xE8;ne-b-poly (m&#xE9;thacrylate de m&#xE9;thyle) Films copolym&#xE8;re dibloc Utilisation sans ouverture microscopie en champ proche IR

Die nanoskaligen chemische Zusammensetzung Variationen der Oberfl&auml;chen d&uuml;nner Schichten von Polystyrol-b-Poly(methylmethacrylat) (PS-b-PMMA) Diblock Copolymere werden untersucht mit apertureless Nahfeld-IR-Mikroskopie. Die Streuung des einfallenden Infrarotstrahl aus einer modulierten Rasterkraft-Mikroskopie (AFM)-Tipp ist mit Homodyne Detektion und Demodulation auf die Tipp-Schwingungsfrequenz sondiert. Eine Zunahme der IR-D&auml;mpfung wird in den PMMA-Reich-Dom&auml;nen mit Wellenzahl Abh&auml;ngigkeit beobachtet, die die Massen-Absorptionsspektrum entspricht. Die Ergebnisse zeigen, dass, obwohl eine kleine Topographie-induzierte Artefakt in die Nahfeld-Bilder zu beobachten ist, die chemische Signatur des Beispiels klar erkannt wird.

Chemische Aufnahmen von der Oberfl&auml;che der monomolekularen Nahfeld-Polystyrol-b-Poly(methylmethacrylat) Diblock Copolymer Filme mit apertureless IR-Mikroskopie.

Le variazioni di composizione chimica su scala nanometrica delle superfici delle pellicole sottili di copolimeri diblock di polistirolo-b-poly(methyl methacrylate) (PMMA-PS-b) sono studiate utilizzando la microscopia di IR apertureless near-field. La dispersione del raggio infrarosso incidente da una punta di modulato atomic force microscopy (AFM) &egrave; sondata tramite rilevamento omodino e demodulazione alla frequenza di oscillazione di punta. &Egrave; osservato un aumento dell&#39;attenuazione IR nei domini PMMA-ricco con una dipendenza dal numero d&#39;onda che &egrave; coerenza con lo spettro di assorbimento di massa. I risultati indicano che, anche se un piccolo artefatto topografia-indotta pu&ograve; essere osservato nelle immagini di campo vicino, viene rilevata chiaramente la firma chimica del campione.

Chimica della superficie della auto-assemblati di imaging film di copolimero diblock polistirolo-b-poly(methyl methacrylate) utilizzando apertureless IR microscopia a campo.

&#xFF08;PS-B-PMMA&#xFF09;&#xFF08;&#x30E1;&#x30C1;&#x30EB;&#x30E1;&#x30BF;&#x30AF;&#x30EA;&#x30EC;&#x30FC;&#x30C8;&#xFF09;&#x3001;&#x30DD;&#x30EA;&#x30B9;&#x30C1;&#x30EC;&#x30F3;-b-&#x30DD;&#x30EA;&#x30B8;&#x30D6;&#x30ED;&#x30C3;&#x30AF;&#x5171;&#x91CD;&#x5408;&#x4F53;&#x306E;&#x8584;&#x819C;&#x8868;&#x9762;&#x306E;&#x30CA;&#x30CE;&#x30B9;&#x30B1;&#x30FC;&#x30EB;&#x306E;&#x5316;&#x5B66;&#x7D44;&#x6210;&#x306E;&#x5909;&#x52D5;&#x306F;apertureless&#x8FD1;&#x63A5;&#x5834;&#x8D64;&#x5916;&#x9855;&#x5FAE;&#x93E1;&#x3092;&#x7528;&#x3044;&#x3066;&#x8ABF;&#x3079;&#x305F;&#x3002;&#x5909;&#x8ABF;&#x3055;&#x308C;&#x305F;&#x539F;&#x5B50;&#x9593;&#x529B;&#x9855;&#x5FAE;&#x93E1;&#xFF08;AFM&#xFF09;&#x306E;&#x5148;&#x7AEF;&#x304B;&#x3089;&#x5165;&#x5C04;&#x3059;&#x308B;&#x8D64;&#x5916;&#x7DDA;&#x30D3;&#x30FC;&#x30E0;&#x306E;&#x6563;&#x4E71;&#x306F;&#x3001;&#x5148;&#x7AEF;&#x306E;&#x767A;&#x632F;&#x5468;&#x6CE2;&#x6570;&#x3067;&#x30DB;&#x30E2;&#x30C0;&#x30A4;&#x30F3;&#x691C;&#x51FA;&#x3068;&#x5FA9;&#x8ABF;&#x3092;&#x4F7F;&#x7528;&#x3057;&#x3066;&#x30D7;&#x30ED;&#x30FC;&#x30D6;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002; IR&#x6E1B;&#x8870;&#x306E;&#x5897;&#x52A0;&#x306F;&#x3001;&#x30D0;&#x30EB;&#x30AF;&#x306E;&#x5438;&#x53CE;&#x30B9;&#x30DA;&#x30AF;&#x30C8;&#x30EB;&#x3068;&#x4E00;&#x81F4;&#x3057;&#x3066;&#x3044;&#x308B;&#x6CE2;&#x6570;&#x4F9D;&#x5B58;&#x6027;&#x3092;&#x6301;&#x3064;PMMA-&#x30EA;&#x30C3;&#x30C1;&#x30C9;&#x30E1;&#x30A4;&#x30F3;&#x3067;&#x89B3;&#x5BDF;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x7D50;&#x679C;&#x306F;&#x3001;&#x5C0F;&#x5730;&#x5F62;&#x306B;&#x3088;&#x3063;&#x3066;&#x8A98;&#x767A;&#x3055;&#x308C;&#x308B;&#x30A2;&#x30FC;&#x30C6;&#x30A3;&#x30D5;&#x30A1;&#x30AF;&#x30C8;&#x306F;&#x3001;&#x30CB;&#x30A2;&#x30D5;&#x30A3;&#x30FC;&#x30EB;&#x30C9;&#x306E;&#x753B;&#x50CF;&#x3067;&#x89B3;&#x5BDF;&#x3059;&#x308B;&#x3053;&#x3068;&#x304C;&#x3067;&#x304D;&#x308B;&#x306B;&#x3082;&#x304B;&#x304B;&#x308F;&#x3089;&#x305A;&#x3001;&#x30B5;&#x30F3;&#x30D7;&#x30EB;&#x306E;&#x5316;&#x5B66;&#x7F72;&#x540D;&#x304C;&#x660E;&#x78BA;&#x306B;&#x691C;&#x51FA;&#x3055;&#x308C;&#x305F;&#x3053;&#x3068;&#x3092;&#x793A;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;

Apertureless&#x8FD1;&#x63A5;&#x5834;&#x8D64;&#x5916;&#x9855;&#x5FAE;&#x93E1;&#x3092;&#x7528;&#x3044;&#x305F;&#x81EA;&#x5DF1;&#x7D44;&#x7E54;&#x5316;&#x30DD;&#x30EA;&#x30B9;&#x30C1;&#x30EC;&#x30F3;-b-&#x30DD;&#x30EA;&#xFF08;&#x30E1;&#x30C1;&#x30EB;&#x30E1;&#x30BF;&#x30AF;&#x30EA;&#x30EC;&#x30FC;&#x30C8;&#xFF09;&#x30B8;&#x30D6;&#x30ED;&#x30C3;&#x30AF;&#x5171;&#x91CD;&#x5408;&#x4F53;&#x8584;&#x819C;&#x306E;&#x8868;&#x9762;&#x306E;&#x5316;&#x5B66;&#x7684;&#x30A4;&#x30E1;&#x30FC;&#x30B8;&#x30F3;&#x30B0;

&#xD3F4;&#xB9AC;&#xC2A4; &#xD2F0; &#xB80C; b poly(methyl methacrylate) (PS-b-PMMA) diblock &#xACF5;&#xC911; &#xD569;&#xCCB4;&#xC758; &#xBC15;&#xB9C9;&#xC758; &#xD45C;&#xBA74; &#xB098;&#xB178; &#xD654;&#xD559; &#xC131;&#xBD84; &#xBCC0;&#xD654;&#xB294; apertureless &#xD544;&#xB4DC; &#xADFC;&#xCC98; IR &#xD604;&#xBBF8;&#xACBD;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xC870;&#xC0AC; &#xD588;&#xB2E4;. &#xBCC0;&#xC870; &#xB41C; &#xC6D0;&#xC790; &#xD798; &#xD604;&#xBBF8;&#xACBD; (AFM) &#xB05D;&#xC5D0;&#xC11C; &#xC0AC;&#xACE0; &#xC801;&#xC678;&#xC120; &#xBE54; &#xC0B0;&#xB780; &#xD301; &#xBC1C;&#xC9C4; &#xC8FC;&#xD30C;&#xC218; homodyne &#xAC80;&#xCD9C; &#xD558; &#xACE0; &#xBCF5;&#xC870;&#xB97C; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xC870;&#xC0AC; &#xC774;&#xB2E4;. IR &#xAC10;&#xC1E0; &#xC99D;&#xAC00; &#xB300;&#xB7C9; &#xD761;&#xC218; &#xC2A4;&#xD399;&#xD2B8;&#xB7FC;&#xACFC; &#xC77C;&#xCE58; wavenumber &#xC758;&#xC874;&#xB3C4;&#xC640; PMMA &#xD48D;&#xBD80;&#xD55C; &#xB3C4;&#xBA54;&#xC778;&#xC5D0;&#xC11C; &#xAD00;&#xCC30; &#xB429;&#xB2C8;&#xB2E4;. &#xACB0;&#xACFC; &#xBE44;&#xB85D; &#xC791;&#xC740; &#xC9C0;&#xD615; &#xC720;&#xB3C4; &#xC544;&#xD2F0;&#xD329;&#xD2B8; &#xADFC;&#xCC98; &#xD544;&#xB4DC; &#xC774;&#xBBF8;&#xC9C0;&#xC5D0;&#xC11C; &#xAD00;&#xCC30;&#xD560; &#xC218; &#xC788;&#xB2E4;, &#xC0D8;&#xD50C;&#xC758; &#xD654;&#xD559; &#xC11C;&#xBA85;&#xC774; &#xBA85;&#xD655; &#xD558; &#xAC8C; &#xAC10;&#xC9C0; &#xB418; &#xB098;&#xD0C0;&#xB0C5;&#xB2C8;&#xB2E4;.

&#xD654;&#xD559; &#xD14C;&#xD06C;&#xB180;&#xB85C;&#xC9C0;&#xC758; &#xC774;&#xBBF8;&#xC9D5; apertureless&#xB97C; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xD3F4;&#xB9AC;&#xC2A4; &#xD2F0; &#xB80C; b poly(methyl methacrylate) diblock &#xCF54; &#xD3F4;&#xB9AC;&#xBA38; &#xD544;&#xB984; &#xADFC;&#xCC98;-&#xD544;&#xB4DC; &#xC801;&#xC678;&#xC120; &#xD604;&#xBBF8;&#xACBD;.

Las variaciones qu&#xED;micas nanoescala composici&#xF3;n de las superficies de las pel&#xED;culas delgadas de poliestireno-b-poli (metacrilato de metilo) (PS-b-PMMA) copol&#xED;meros de dos bloques se investig&#xF3; mediante apertureless microscop&#xED;a de campo cercano IR. La dispersi&#xF3;n del haz incidente infrarroja de un microscopio de fuerza modulada at&#xF3;mica (AFM) de punta se explora mediante la detecci&#xF3;n de homodino y demodulaci&#xF3;n de la frecuencia de oscilaci&#xF3;n punta. Un aumento de la atenuaci&#xF3;n de IR se observa en los dominios de PMMA ricos con una dependencia n&#xFA;mero de onda que sea coherente con el espectro de absorci&#xF3;n a granel. Los resultados indican que, aunque una peque&#xF1;a topograf&#xED;a inducida artefacto se puede observar en las im&#xE1;genes de campo pr&#xF3;ximo, la firma qu&#xED;mica de la muestra se detecta con claridad.

Qu&#xED;mica im&#xE1;genes de la superficie de la auto-ensambladas de poliestireno-b-poli (metacrilato de metilo) Pel&#xED;culas copol&#xED;mero dibloque Apertureless Usando microscop&#xED;a de campo cercano IR

&#x6DC0;&#x7C89;&#x6837;&#x7EA4;&#x7EF4;&#x75BE;&#x75C5;&#x7684;&#x7279;&#x70B9;&#x662F;&#x5F02;&#x5E38;&#x751F;&#x4EA7;&#x7684;&#x805A;&#x5408;&#x86CB;&#x767D;&#x548C;&#x4E0E;&#x8BB8;&#x591A;&#x7C7B;&#x578B;&#x7684;&#x795E;&#x7ECF;&#x548C;&#x8EAB;&#x4F53;&#x4E0A;&#x7684;&#x9000;&#x884C;&#x6027;&#x75BE;&#x75C5;&#x76F8;&#x5173;&#x8054;&#x3002;X &#x5C04;&#x7EBF;&#x884D;&#x5C04;&#x6280;&#x672F;&#x3001; &#x56FA;&#x6001;&#x9B54;&#x672F;&#x89D2;&#x65CB;&#x8F6C;&#x6838;&#x78C1;&#x5171;&#x632F;&#x5149;&#x8C31;&#x3001; &#x5706;&#x4E8C;&#x8272; (CD) &#x5149;&#x8C31;&#x548C;&#x900F;&#x5C04;&#x7535;&#x5B50;&#x663E;&#x5FAE;&#x955C;&#x7814;&#x7A76;&#x5DF2;&#x7528;&#x4E8E;&#x68C0;&#x6D4B;&#x548C;&#x68C0;&#x67E5;&#x7684;&#x5316;&#x5B66;&#x3001; &#x7535;&#x5B50;&#x3001; &#x6750;&#x6599;&#x548C;&#x7ED3;&#x6784;&#x7279;&#x6027;&#x7684;&#x6DC0;&#x7C89;&#x6837;&#x7EA4;&#x7EF4;&#x5728;&#x57C3;&#x7A7A;&#x95F4;&#x5206;&#x8FA8;&#x7387;&#x3002;&#x4E0D;&#x8FC7;&#xFF0C;x &#x5C04;&#x7EBF;&#x884D;&#x5C04;&#x7814;&#x7A76;&#x9700;&#x8981;&#x6676;&#x4F53;&#x7EA4;&#x7EF4;&#x8981;&#x5206;&#x6790;&#xFF0C;&#x867D;&#x7136;&#x5176;&#x4ED6;&#x6280;&#x672F;&#x53EF;&#x4EE5;&#x53EA;&#x63A2;&#x6D4B;&#x5668;&#x6279;&#x91CF;&#x89E3;&#x51B3;&#x65B9;&#x6848;&#x6216;&#x56FA;&#x4F53;&#x6837;&#x54C1;&#x3002;&#x5728;&#x8FD9;&#x91CC;&#x62A5;&#x544A;&#x7684;&#x5DE5;&#x4F5C;&#xFF0C;apertureless &#x8FD1;&#x573A;&#x7EA2;&#x5916;&#x663E;&#x5FAE;&#x955C; &#xFF08;ANSIM&#xFF09; &#x7528;&#x6765;&#x63A2;&#x6D4B;&#x4E2A;&#x522B;&#x6DC0;&#x7C89;&#x6837;&#x7EA4;&#x7EF4;&#x4ECE;&#x4F53;&#x5916;&#x89E3;&#x51B3;&#x65B9;&#x6848;&#x6240;&#x4F5C;&#x7684;&#x4E8C;&#x7EA7;&#x7ED3;&#x6784;&#x3002;&#x540C;&#x65F6;&#x5730;&#x5F62;&#x548C;&#x7EA2;&#x5916;&#x56FE;&#x50CF;&#x7684;&#x4E2A;&#x522B;&#x6DC0;&#x7C89;&#x6837;&#x7EA4;&#x7EF4;&#x5408;&#x6210; #21-31 &#x80BD;&#x7247;&#x6BB5;&#x7684; &beta; 2-&#x5FAE;&#x7403;&#x86CB;&#x767D;&#x83B7;&#x5F97;&#x3002;&#x4F7F;&#x7528;&#x6B64;&#x6280;&#x672F;&#xFF0C;&#x6DC0;&#x7C89;&#x6837;&#x7EA4;&#x7EF4;&#x7684;&#x7EA2;&#x5916;&#x5149;&#x8C31;&#x83B7;&#x5F97;&#x7A7A;&#x95F4;&#x5206;&#x8FA8;&#x7387;&#x5C0F;&#x4E8E; 30 nm&#x3002;&#x9700;&#x8981;&#x6307;&#x51FA;&#x7684;&#x662F;&#x5B9E;&#x9A8C;&#x5206;&#x6563;&#x5916;&#x5730;&#x8C31;&#x76F8;&#x5173;&#x56E0;&#x7D20;&#x5F3A;&#x70C8;&#x4E0E;&#x8BA1;&#x7B97;&#x4F7F;&#x7528;&#x8FDC;&#x573A;&#x5438;&#x6536;&#x8C31;&#x3002;&#x6DC0;&#x7C89;&#x6837;&#x7EA4;&#x7EF4;&#x7684;&#x8FD1;&#x573A;&#x56FE;&#x50CF;&#x8868;&#x73B0;&#x51FA;&#x5F88;&#x591A;&#x4F4E;&#x6563;&#x5C04;&#x7684;&#x7EA6; 16 &#x65F6; 30 cm(-1) &#x7EA2;&#x5916;&#x8F90;&#x5C04;&#x3002;&#x6B64;&#x5916;&#xFF0C;&#x8FD1;&#x573A;&#x56FE;&#x50CF;&#x8FD8;&#x8868;&#x660E;&#x4E2A;&#x4EBA;&#x6DC0;&#x7C89;&#x6837;&#x7EA4;&#x7EF4;&#x6210;&#x5206;&#x548C;/&#x6216;&#x7ED3;&#x6784;&#x53D8;&#x5F02;&#x5728;&#x573A;&#x3002;

&#x6210;&#x50CF;&#x4E2A;&#x522B;&#x6DC0;&#x7C89;&#x6837;&#x7EA4;&#x7EF4;&#x7684;&#x4F7F;&#x7528;&#x8FD1;&#x573A;&#x7EA2;&#x5916;&#x5149;&#x8C31;&#x7684; &beta; 2-&#x5FAE;&#x7403;&#x86CB;&#x767D;&#x7247;&#x6BB5;&#x7684;&#x4E8C;&#x7EA7;&#x7684;&#x7ED3;&#x6784;&#x3002;

Amyloid fibril diseases are characterized by the abnormal production of aggregated proteins and are associated with many types of neuro- and physically degenerative diseases. X-ray diffraction techniques, solid-state magic-angle spinning NMR spectroscopy, circular dichroism (CD) spectroscopy, and transmission electron microscopy studies have been utilized to detect and examine the chemical, electronic, material, and structural properties of amyloid fibrils at up to angstrom spatial resolution. However, X-ray diffraction studies require crystals of the fibril to be analyzed, while other techniques can only probe the bulk solution or solid samples. In the work reported here, apertureless near-field scanning infrared microscopy (ANSIM) was used to probe the secondary structure of individual amyloid fibrils made from an in vitro solution. Simultaneous topographic and infrared images of individual amyloid fibrils synthesized from the #21-31 peptide fragment of Î²(2)-microglobulin were acquired. Using this technique, IR spectra of the amyloid fibrils were obtained with a spatial resolution of less than 30 nm. It is observed that the experimental scattered field spectrum correlates strongly with that calculated using the far-field absorption spectrum. The near-field images of the amyloid fibrils exhibit much lower scattering of the IR radiation at approximately 1630 cm(-1). In addition, the near-field images also indicate that composition and/or structural variations among individual amyloid fibrils were present.

Imaging secondary structure of individual amyloid fibrils of a Î²2-microglobulin fragment using near-field infrared spectroscopy.

Amylo&#xEF;des fibrilles maladies sont caract&#xE9;ris&#xE9;es par la production anormale de prot&#xE9;ines agr&#xE9;g&#xE9;es et sont associ&#xE9;s &#xE0; de nombreux types de maladies neuro-d&#xE9;g&#xE9;n&#xE9;ratives et physiquement. Des techniques de diffraction des rayons X, &#xE0; l&#x26;#39;&#xE9;tat solide &#xE0; l&#x26;#39;angle magique tournant spectroscopie RMN, dichro&#xEF;sme circulaire (CD) de la spectroscopie, et des &#xE9;tudes microscopie &#xE9;lectronique en transmission ont &#xE9;t&#xE9; utilis&#xE9;s pour d&#xE9;tecter et examiner la chimie, l&#x26;#39;&#xE9;lectronique, les mat&#xE9;riaux et les propri&#xE9;t&#xE9;s structurales de fibrilles amylo&#xEF;des jusqu&#x26;#39;&#xE0; &#xE0; angstr&#xF6;m r&#xE9;solution spatiale. Cependant, des &#xE9;tudes de diffraction des rayons X n&#xE9;cessitent des cristaux de la fibrille &#xE0; analyser, tandis que d&#x26;#39;autres techniques ne peuvent sonder la solution en vrac ou des &#xE9;chantillons solides. Dans le travail pr&#xE9;sent&#xE9; ici, sans ouverture microscopie &#xE0; balayage &#xE0; champ proche infrarouge (ANSIM) a &#xE9;t&#xE9; utilis&#xE9; pour sonder la structure secondaire de fibrilles amylo&#xEF;des individuelles faites &#xE0; partir d&#x26;#39;une solution dans in vitro. Simultan&#xE9;es images topographiques et infrarouge de fibrilles amylo&#xEF;des individuels synth&#xE9;tis&#xE9;s &#xE0; partir du fragment peptidique de 21 &#xE0; 31 # &#x3B2; (2)-microglobuline ont &#xE9;t&#xE9; acquises. En utilisant cette technique, les spectres IR des fibrilles amylo&#xEF;des ont &#xE9;t&#xE9; obtenus avec une r&#xE9;solution spatiale de moins de 30 nm. On observe que le spectre du champ exp&#xE9;rimental diffus&#xE9;e est fortement corr&#xE9;l&#xE9; avec celui calcul&#xE9; en utilisant le spectre d&#x26;#39;absorption en champ lointain. Les images en champ proche des fibrilles amylo&#xEF;des pr&#xE9;sentent diffusion beaucoup plus faible du rayonnement IR &#xE0; environ 1630 cm -1). En outre, les images en champ proche aussi indiquer que la composition et / ou des variations structurelles entre les fibrilles amylo&#xEF;des individuels &#xE9;taient pr&#xE9;sents.

Imagerie structure secondaire des fibrilles amylo&#xEF;des individuels d&#x26;#39;un fragment &#x3B2;2-microglobuline aide en champ proche spectroscopie infrarouge

Amyloid Fibrille Krankheiten zeichnen sich durch die abnormale Produktion von aggregierten Proteinen und viele Arten von Neuro- und physisch degenerativen Krankheiten zugeordnet sind. R&ouml;ntgenbeugung Techniken, Solid-State-Magic-Angle-Spinning-NMR-Spektroskopie, Circulardichroismus (CD)-Spektroskopie und Elektronenmikroskopie Untersuchungen zur &Uuml;bertragung haben erkennen und untersuchen, chemische, elektronische, Material und strukturellen Eigenschaften des Amyloid-Fibrillen bei Angstr&ouml;m r&auml;umliche Aufl&ouml;sung bis verwandt worden. -R&ouml;ntgenbeugung erfordern jedoch Kristalle von der Fibrille analysiert werden, w&auml;hrend andere Techniken nur der Gro&szlig;teil L&ouml;sung oder festen Proben Pr&uuml;fpunkt k&ouml;nnen. In der Arbeit, die hier berichteten wurde apertureless Nahfeld-Infrarot-Elektronenmikroskopie (ANSIM) zur Sonde die Sekund&auml;rstruktur einzelne Amyloid-Fibrillen gebildet von einer in-vitro-L&ouml;sung. Gleichzeitige Topographische und Infrarot-Bilder einzelner Amyloid-Fibrillen synthetisiert aus der #21-31-Peptid-Fragment des &beta;-2-Mikroglobulin wurden erworben. Mit dieser Technik, IR-Spektren der Amyloid-Fibrillen wurden erzielt mit einer r&auml;umlichen Aufl&ouml;sung von weniger als 30 nm. Es wird beobachtet, dass das experimentelle Feld Spektrum korreliert mit dem anhand der Fernfeld Absorptionsspektrum stark verstreut. Die Nahfeld-Bilder der Amyloid-Fibrillen zeigen viel geringere Streuung der IR-Strahlung bei ca. 1630 cm(-1). Dar&uuml;ber hinaus zeigen die Nahfeld-Bilder auch, dass die Zusammensetzung und/oder strukturelle Unterschiede zwischen den einzelnen Amyloid-Fibrillen anwesend waren.

Imaging Sekund&auml;rstruktur einzelne Amyloid-Fibrillen eines &szlig;2-Mikroglobulin-Fragment mit Nahfeld-IR-Spektroskopie.

Fibrillare amiloide malattie sono caratterizzate da una produzione anormale di proteine aggregate e sono associate con molti tipi di neuro - e malattie degenerative fisicamente. Tecniche di diffrazione a raggi x, spettroscopia NMR allo stato solido magic angle spinning, spettroscopia di Dicroismo circolare (CD) e gli studi di microscopia elettronica di trasmissione sono stati utilizzati per individuare ed esaminare le propriet&agrave; strutturali di fibrille amiloidi a fino a risoluzione spaziale angstrom e materiale chimico, elettronico. Tuttavia, studi di diffrazione a raggi x richiedono cristalli di fibrillare per essere analizzati, mentre altre tecniche possono solo sonda la soluzione alla rinfusa o campioni solidi. Nel lavoro riportato qui, apertureless campo vicino microscopia a raggi infrarossi (ANSIM) &egrave; stato usato per sondare la struttura secondaria di fibrille amiloidi individuale fatta da una soluzione in vitro. Simultanee immagini topografiche e ad infrarossi di singole fibrille amiloidi sintetizzati dalla #21-31 frammento peptidico di &beta; (2)-microglobulina sono stati acquisiti. Utilizzando questa tecnica, gli spettri IR di fibrille amiloidi sono stati ottenuti con una risoluzione spaziale di meno di 30 nm. &Egrave; stato osservato che la sperimentale sparsi campo dello spettro &egrave; correlata fortemente con quello calcolato utilizzando lo spettro di assorbimento di campo lontano. Le immagini del vicino-campo di fibrille amiloidi esibiscono molto bassa dispersione della radiazione IR a cm(-1) circa 1630. Inoltre, le immagini del vicino-campo indicano che variazioni di composizione e/o strutturali tra fibrille amiloidi individuali erano presenti.

Struttura secondaria di fibrille amiloidi individuale di un frammento di &beta;2-microglobulina mediante spettroscopia infrarossa vicino-campo di Imaging.

&#x30A2;&#x30DF;&#x30ED;&#x30A4;&#x30C9;&#x7DDA;&#x7DAD;&#x306E;&#x75BE;&#x60A3;&#x306F;&#x3001;&#x51DD;&#x96C6;&#x3057;&#x305F;&#x30BF;&#x30F3;&#x30D1;&#x30AF;&#x8CEA;&#x306E;&#x7570;&#x5E38;&#x306A;&#x7523;&#x751F;&#x306B;&#x3088;&#x3063;&#x3066;&#x7279;&#x5FB4;&#x4ED8;&#x3051;&#x3089;&#x308C;&#x3001;&#x795E;&#x7D4C;&#x3001;&#x7269;&#x7406;&#x7684;&#x306B;&#x5909;&#x6027;&#x75BE;&#x60A3;&#x306E;&#x591A;&#x304F;&#x306E;&#x7A2E;&#x985E;&#x306B;&#x95A2;&#x9023;&#x4ED8;&#x3051;&#x3089;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002; X&#x7DDA;&#x56DE;&#x6298;&#x6280;&#x8853;&#x3001;&#x30BD;&#x30EA;&#x30C3;&#x30C9;&#xB7;&#x30B9;&#x30C6;&#x30FC;&#x30C8;&#xB7;&#x30DE;&#x30B8;&#x30C3;&#x30AF;&#x89D2;NMR&#x5206;&#x5149;&#x6CD5;&#x3001;&#x5186;&#x504F;&#x5149;&#x4E8C;&#x8272;&#x6027;&#xFF08;CD&#xFF09;&#x5206;&#x5149;&#x6CD5;&#x3092;&#x56DE;&#x8EE2;&#x3057;&#x3001;&#x900F;&#x904E;&#x578B;&#x96FB;&#x5B50;&#x9855;&#x5FAE;&#x93E1;&#x306E;&#x7814;&#x7A76;&#x306F;&#x3001;&#x6700;&#x5927;&#x3067;&#x5316;&#x5B66;&#x3001;&#x96FB;&#x5B50;&#x3001;&#x6750;&#x6599;&#x3001;&#x304A;&#x3088;&#x3073;&#x30A2;&#x30DF;&#x30ED;&#x30A4;&#x30C9;&#x7DDA;&#x7DAD;&#x306E;&#x69CB;&#x9020;&#x7279;&#x6027;&#x3092;&#x691C;&#x51FA;&#x3057;&#x3066;&#x8ABF;&#x3079;&#x308B;&#x305F;&#x3081;&#x306B;&#x5229;&#x7528;&#x3055;&#x308C;&#x3066;&#x3044;&#x308B;&#x30AA;&#x30F3;&#x30B0;&#x30B9;&#x30C8;&#x30ED;&#x30FC;&#x30E0;&#x306E;&#x7A7A;&#x9593;&#x5206;&#x89E3;&#x80FD;&#x3002;&#x3057;&#x304B;&#x3057;&#x3001;X&#x7DDA;&#x56DE;&#x6298;&#x306E;&#x7814;&#x7A76;&#x3067;&#x306F;&#x3001;&#x4ED6;&#x306E;&#x30C6;&#x30AF;&#x30CB;&#x30C3;&#x30AF;&#x3060;&#x3051;&#x3067;&#x30D0;&#x30EB;&#x30AF;&#x6EB6;&#x6DB2;&#x307E;&#x305F;&#x306F;&#x56FA;&#x4F53;&#x8A66;&#x6599;&#x3092;&#x8ABF;&#x3079;&#x308B;&#x3053;&#x3068;&#x304C;&#x3067;&#x304D;&#x307E;&#x3059;&#x304C;&#x7DDA;&#x7DAD;&#x306E;&#x7D50;&#x6676;&#x306F;&#x3001;&#x5206;&#x6790;&#x3059;&#x308B;&#x5FC5;&#x8981;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;&#x3053;&#x3053;&#x3067;&#x5831;&#x544A;&#x3055;&#x308C;&#x305F;&#x7814;&#x7A76;&#x3067;&#x306F;&#x3001;&#x8D64;&#x5916;&#x7DDA;&#x9855;&#x5FAE;&#x93E1;&#xFF08;ANSIM&#xFF09;&#x3092;&#x30B9;&#x30AD;&#x30E3;&#x30F3;apertureless&#x30CB;&#x30A2;&#x30D5;&#x30A3;&#x30FC;&#x30EB;&#x30C9;&#x306F;&#x3001;in vitro&#x3067;&#x306E;&#x30BD;&#x30EA;&#x30E5;&#x30FC;&#x30B7;&#x30E7;&#x30F3;&#x304B;&#x3089;&#x4F5C;&#x3089;&#x308C;&#x305F;&#x500B;&#x3005;&#x306E;&#x30A2;&#x30DF;&#x30ED;&#x30A4;&#x30C9;&#x7DDA;&#x7DAD;&#x306E;&#x4E8C;&#x6B21;&#x69CB;&#x9020;&#x3092;&#x8ABF;&#x3079;&#x308B;&#x305F;&#x3081;&#x306B;&#x4F7F;&#x7528;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3057;&#x305F;&#x3002; &#x3B2;&#xFF08;2&#xFF09;&#x30DF;&#x30AF;&#x30ED;&#x30B0;&#x30ED;&#x30D6;&#x30EA;&#x30F3;&#x306E;&#xFF03;21&#x304B;&#x3089;31&#x30DA;&#x30D7;&#x30C1;&#x30C9;&#x65AD;&#x7247;&#x304B;&#x3089;&#x5408;&#x6210;&#x3055;&#x308C;&#x305F;&#x500B;&#x3005;&#x306E;&#x30A2;&#x30DF;&#x30ED;&#x30A4;&#x30C9;&#x7DDA;&#x7DAD;&#x306E;&#x540C;&#x6642;&#x5730;&#x5F62;&#x3068;&#x8D64;&#x5916;&#x7DDA;&#x753B;&#x50CF;&#x3092;&#x53D6;&#x5F97;&#x3057;&#x305F;&#x3002;&#x3053;&#x306E;&#x30C6;&#x30AF;&#x30CB;&#x30C3;&#x30AF;&#x3092;&#x4F7F;&#x7528;&#x3057;&#x3066;&#x3001;&#x30A2;&#x30DF;&#x30ED;&#x30A4;&#x30C9;&#x7DDA;&#x7DAD;&#x306E;IR&#x30B9;&#x30DA;&#x30AF;&#x30C8;&#x30EB;&#x306F;&#x3001;30nm&#x672A;&#x6E80;&#x306E;&#x7A7A;&#x9593;&#x5206;&#x89E3;&#x80FD;&#x304C;&#x5F97;&#x3089;&#x308C;&#x305F;&#x3002;&#x305D;&#x308C;&#x306F;&#x5B9F;&#x9A13;&#x7684;&#x306A;&#x6563;&#x4E71;&#x754C;&#x30B9;&#x30DA;&#x30AF;&#x30C8;&#x30EB;&#x306F;&#x9060;&#x65B9;&#x754C;&#x5438;&#x53CE;&#x30B9;&#x30DA;&#x30AF;&#x30C8;&#x30EB;&#x3092;&#x7528;&#x3044;&#x3066;&#x8A08;&#x7B97;&#x3057;&#x3066;&#x3044;&#x308B;&#x3068;&#x5F37;&#x304F;&#x76F8;&#x95A2;&#x3059;&#x308B;&#x3053;&#x3068;&#x304C;&#x89B3;&#x5BDF;&#x3055;&#x308C;&#x308B;&#x3002;&#x30A2;&#x30DF;&#x30ED;&#x30A4;&#x30C9;&#x7DDA;&#x7DAD;&#x306E;&#x8FD1;&#x8996;&#x91CE;&#x200B;&#x200B;&#x50CF;&#x306F;&#x3001;&#x7D04;1630&#x30BB;&#x30F3;&#x30C1;&#x30E1;&#x30FC;&#x30C8;&#x30EB;&#xFF08;-1&#xFF09;&#x3067;&#x8D64;&#x5916;&#x7DDA;&#x653E;&#x5C04;&#x306E;&#x306F;&#x308B;&#x304B;&#x306B;&#x4F4E;&#x3044;&#x6563;&#x4E71;&#x3092;&#x793A;&#x3059;&#x3002;&#x3055;&#x3089;&#x306B;&#x3001;&#x30CB;&#x30A2;&#x30D5;&#x30A3;&#x30FC;&#x30EB;&#x30C9;&#x306E;&#x30A4;&#x30E1;&#x30FC;&#x30B8;&#x306F;&#x307E;&#x305F;&#x3001;&#x7D44;&#x6210;&#x7269;&#x304A;&#x3088;&#x3073;/&#x307E;&#x305F;&#x306F;&#x500B;&#x3005;&#x306E;&#x30A2;&#x30DF;&#x30ED;&#x30A4;&#x30C9;&#x7DDA;&#x7DAD;&#x306E;&#x69CB;&#x9020;&#x7684;&#x5909;&#x5316;&#x304C;&#x5B58;&#x5728;&#x3057;&#x3066;&#x3044;&#x305F;&#x3053;&#x3068;&#x3092;&#x793A;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;

&#x8FD1;&#x63A5;&#x5834;&#x8D64;&#x5916;&#x5206;&#x5149;&#x6CD5;&#x3092;&#x7528;&#x3044;&#x305F;&#x3B2;2-&#x30DF;&#x30AF;&#x30ED;&#x30B0;&#x30ED;&#x30D6;&#x30EA;&#x30F3;&#x306E;&#x30D5;&#x30E9;&#x30B0;&#x30E1;&#x30F3;&#x30C8;&#x306E;&#x500B;&#x3005;&#x306E;&#x30A2;&#x30DF;&#x30ED;&#x30A4;&#x30C9;&#x7DDA;&#x7DAD;&#x306E;&#x30A4;&#x30E1;&#x30FC;&#x30B8;&#x30F3;&#x30B0;&#x4E8C;&#x6B21;&#x69CB;&#x9020;

&#xB179;&#xB9D0; &#xCCB4; fibril &#xC9C8;&#xBCD1; &#xC9D1;&#xACC4; &#xB41C; &#xB2E8;&#xBC31;&#xC9C8;&#xC758; &#xBE44;&#xC815;&#xC0C1;&#xC801;&#xC778; &#xC0DD;&#xC0B0;&#xC5D0; &#xC758;&#xD574; &#xD2B9;&#xC9D5; &#xBC0F; &#xB9CE;&#xC740; &#xC885;&#xB958;&#xC758; &#xC2E0;&#xACBD;-&#xC640; &#xBB3C;&#xB9AC;&#xC801;&#xC73C;&#xB85C; &#xD1F4;&#xD589; &#xC131; &#xC9C8;&#xD658;&#xC5D0; &#xC5F0;&#xAD00; &#xB41C;. X-&#xC120; &#xD68C;&#xC808; &#xAE30;&#xBC95;, &#xACE0;&#xCCB4; &#xB9E4;&#xC9C1; &#xC575;&#xAE00; &#xD68C;&#xC804; NMR &#xBD84;&#xAD11;&#xD559;, &#xC6D0;&#xD615; &#xC591;&#xC0C9;&#xC131; (CD) &#xBD84;&#xAD11;&#xD559; &#xBC0F; &#xC804;&#xC1A1; &#xC804;&#xC790; &#xD604;&#xBBF8;&#xACBD; &#xC5F0;&#xAD6C; &#xAC10;&#xC9C0; &#xD558; &#xC5EC; &#xD654;&#xD559;, &#xC804;&#xC790;, &#xC18C;&#xC7AC; &#xBC0F; &#xCD5C;&#xB300; angstrom &#xACF5;&#xAC04; &#xD574;&#xC0C1;&#xB3C4;&#xC5D0; &#xB179;&#xB9D0; &#xCCB4; &#xC18C;&#xC758; &#xAD6C;&#xC870;&#xC801; &#xC18D;&#xC131; &#xAC80;&#xC0AC; &#xD65C;&#xC6A9; &#xB418;&#xC5C8;&#xC2B5;&#xB2C8;&#xB2E4;. &#xADF8;&#xB7EC;&#xB098;, x-&#xC120; &#xD68C;&#xC808; &#xC5F0;&#xAD6C; &#xB2E4;&#xB978; &#xAE30;&#xC220;&#xC744; &#xB300;&#xB7C9; &#xC194;&#xB8E8;&#xC158; &#xB610;&#xB294; &#xACE0;&#xCCB4; &#xC0D8;&#xD50C; &#xD504;&#xB85C;&#xBE0C;&#xB9CC; &#xC218; &#xD558;&#xB294; &#xB3D9;&#xC548; &#xBD84;&#xC11D; fibril &#xACB0;&#xC815; &#xD544;&#xC694;. &#xC5EC;&#xAE30; &#xBCF4;&#xACE0; &#xC791;&#xC5C5; &#xD544;&#xB4DC; &#xC2A4;&#xCE94; &#xC801;&#xC678;&#xC120; &#xD604;&#xBBF8;&#xACBD; &#xAC80;&#xC0AC; &#xBC95; (&#xC548;&#xC2EC;) &#xADFC;&#xCC98; apertureless &#xCCB4; &#xC678; &#xC194;&#xB8E8;&#xC158;&#xC5D0;&#xC11C; &#xB9CC;&#xB4E0; &#xAC1C;&#xBCC4; &#xB179;&#xB9D0; &#xCCB4; &#xC18C;&#xC758; 2 &#xCC28; &#xAD6C;&#xC870;&#xB97C; &#xC870;&#xC0AC; &#xD558; &#xC0AC;&#xC6A9; &#xB418;&#xC5C8;&#xB2E4;. &#xAC1C;&#xBCC4; &#xB179;&#xB9D0; &#xCCB4; &#xC18C;&#xB294; #21&#xC5D0;&#xC11C; &#xD569;&#xC131;&#xC758; &#xB3D9;&#xC2DC; &#xC9C0;&#xD615; &#xBC0F; &#xC801;&#xC678;&#xC120; &#xC774;&#xBBF8;&#xC9C0;-31 &#xD3A9; &#xD2F0; &#xB4DC; &#xC870;&#xAC01; &beta; (2)-microglobulin&#xC758; &#xC778;&#xC218; &#xD588;&#xB2E4;. &#xB179;&#xB9D0; &#xCCB4; &#xC18C;&#xC758; IR &#xC2A4;&#xD399;&#xD2B8;&#xB7FC; 30 &#xBBF8;&#xB9CC;&#xC758;&#xC758; &#xACF5;&#xAC04; &#xD574;&#xC0C1;&#xB3C4;&#xC640; &#xAC00;&#xC838;&#xC628;&#xC774; &#xAE30;&#xBC95;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC;, &#xB274; &#xBA55;&#xC2DC;&#xCF54;. &#xADF8;&#xB294; &#xC2E4;&#xD5D8;&#xC801;&#xC778; &#xD769;&#xC5B4;&#xC838; &#xD544;&#xB4DC; &#xC2A4;&#xD399;&#xD2B8;&#xB7FC; &#xC5F0;&#xAD00; &#xAC15;&#xB825; &#xD558; &#xAC8C; &#xADF8; &#xBA3C; &#xD544;&#xB4DC; &#xD761;&#xC218; &#xC2A4;&#xD399;&#xD2B8;&#xB7FC;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xACC4;&#xC0B0;&#xC744; &#xAD00;&#xCC30; &#xD569;&#xB2C8;&#xB2E4;. &#xB179;&#xB9D0; &#xCCB4; &#xC18C;&#xC758; &#xADFC;&#xCC98;-&#xD544;&#xB4DC; &#xC774;&#xBBF8;&#xC9C0; &#xC804;&#xC2DC; &#xC57D; 1630 cm(-1)&#xC5D0;&#xC11C; IR &#xBC29;&#xC0AC;&#xC120;&#xC758; &#xD6E8;&#xC52C; &#xB354; &#xB0AE;&#xC740; &#xC0B0;&#xB780;. &#xB610;&#xD55C;, &#xADFC;&#xCC98; &#xD544;&#xB4DC; &#xC774;&#xBBF8;&#xC9C0;&#xB294; &#xB610;&#xD55C; &#xAC1C;&#xBCC4; &#xB179;&#xB9D0; &#xCCB4; &#xC18C; &#xAC00;&#xC6B4;&#xB370; &#xC870;&#xC131; &#xBC0F; &#xAD6C;&#xC870; &#xBCC0;&#xD615;&#xC744; &#xCC38;&#xC11D; &#xD588;&#xB2E4; &#xB098;&#xD0C0;&#xB0C5;&#xB2C8;&#xB2E4;.

&#xADFC;&#xCC98;-&#xD544;&#xB4DC; &#xC801;&#xC678;&#xC120; &#xBD84;&#xAD11;&#xD559;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &beta;2 microglobulin &#xC870;&#xAC01;&#xC758; &#xAC1C;&#xBCC4; &#xB179;&#xB9D0; &#xCCB4; &#xC18C;&#xC758; 2 &#xCC28; &#xAD6C;&#xC870; &#xC774;&#xBBF8;&#xC9D5;.

Amiloides enfermedades fibrilla se caracteriza por la producci&#xF3;n anormal de agregados de prote&#xED;nas y est&#xE1;n asociados con muchos tipos de enfermedades neuro-degenerativas y f&#xED;sicamente. T&#xE9;cnicas de rayos X de difracci&#xF3;n, de estado s&#xF3;lido m&#xE1;gica de &#xE1;ngulo hilado espectroscop&#xED;a de RMN, dicro&#xED;smo circular (DC) espectroscopia, y estudios de microscop&#xED;a electr&#xF3;nica de transmisi&#xF3;n se han utilizado para detectar y analizar la qu&#xED;mica, electr&#xF3;nica, materiales, y las propiedades estructurales de fibrillas amiloides en hasta a angstrom resoluci&#xF3;n espacial. Sin embargo, estudios de rayos X de difracci&#xF3;n requieren cristales de la fibrilla para ser analizada, mientras que otras t&#xE9;cnicas s&#xF3;lo puede sondear la soluci&#xF3;n a granel o muestras s&#xF3;lidas. En el trabajo aqu&#xED;, apertureless microscop&#xED;a de campo cercano de escaneado por infrarrojos (ANSIM) se utiliz&#xF3; para investigar la estructura secundaria de las fibrillas amiloides individuales elaborados a partir de una en una soluci&#xF3;n in vitro. Simult&#xE1;nea de im&#xE1;genes topogr&#xE1;ficas y de infrarrojos de fibrillas de amiloide individuales sintetizados a partir del fragmento # 21-31 p&#xE9;ptido de &#x3B2; (2)-microglobulina se adquirieron. Usando esta t&#xE9;cnica, los espectros IR de las fibrillas de amiloide se obtuvieron con una resoluci&#xF3;n espacial de menos de 30 nm. Se observa que el espectro experimental campo dispersa se correlaciona fuertemente con la calculada utilizando el espectro de absorci&#xF3;n de campo lejano. Las im&#xE1;genes de campo pr&#xF3;ximo de las fibrillas amiloides exhiben dispersi&#xF3;n mucho menor de la radiaci&#xF3;n IR a aproximadamente 1630 cm -1). Adem&#xE1;s, las im&#xE1;genes de campo cercano tambi&#xE9;n indican que la composici&#xF3;n y / o variaciones estructurales entre fibrillas amiloides individuales estaban presentes.

Imagen de estructura secundaria de fibrillas de amiloide individuales de un fragmento de &#x3B2;2-microglobulina Uso de campo cercano Espectroscop&#xED;a Infrarroja

Spectroscopic ellipsometry has been used to understand the properties of α,α,β-trisnaphthylbenzene (ααβ-TNB) glasses vapor-deposited at a substrate temperature of 295 K (0.85 T(g)). In a single temperature ramping experiment, a range of properties of the as-deposited glass can be measured, including density, fictive temperature, onset temperature, thermal expansion coefficient, and birefringence. The vapor-deposited ααβ-TNB glass is 1.3% more dense than the ordinary glass prepared by cooling at 1 K/min, is found to be birefringent, has a fictive temperature 35 K below that of the ordinary glass, and an onset temperature 20 K above that of the ordinary glass. The thermal expansion coefficient of the vapor-deposited ααβ-TNB glass is 14% lower than that of the ordinary glass, indicating that lower portions of the potential energy landscape have more harmonic potential minima than the parts accessible to the ordinary glass.

Density and birefringence of a highly stable α,α,β-trisnaphthylbenzene glass.

A method for the high-throughput preparation and characterization of vapor-deposited organic glasses is presented. Depositing directly onto a substrate with a large temperature gradient allows many different glasses to be prepared simultaneously. Ellipsometry is used to characterize these glasses, allowing the determination of density, birefringence, and kinetic stability as a function of substrate temperature. For indomethacin, a model glass former, materials up to 1.4% more dense than the liquid-cooled glass can be formed with a continuously tunable range of molecular orientations as determined by the birefringence. By comparing measurements of many properties, we observe three phenomenological temperature regimes. For substrate temperatures from Tg + 11 K to Tg - 8 K, equilibrium states are produced. Between Tg - 8 K and Tg - 31 K, the vapor-deposited materials have the macroscopic properties expected for the equilibrium supercooled liquid while showing local structural anisotropy. At lower substrate temperatures, the properties of the vapor-deposited glasses are strongly influenced by kinetic factors. Different macroscopic properties are no longer correlated with each other in this regime, allowing unusual combinations of properties.

High-throughput ellipsometric characterization of vapor-deposited indomethacin glasses.

Dark, nonradiating plasmonic modes are important in the Raman enhancement efficiency of nanostructures. However, it is challenging to engineer such hotspots with predictable enhancement efficiency through synthesis routes. Here, we demonstrate that spiky nanoshells have designable quadrupole resonances that efficiently enhance Raman scattering with unprecedented reproducibility on the single particle level. The efficiency and reproducibility of Quadrupole Enhanced Raman Scattering (QERS) is due to their heterogeneous structure, which broadens the quadrupole resonance both spatially and spectrally. This spectral breadth allows for simultaneous enhancement of both the excitation and Stokes frequencies. The quadrupole resonance can be tuned by simple modifications of the nanoshell geometry. The combination of tunability, high efficiency, and reproducibility makes these nanoshells an excellent candidate for applications such as biosensing, nanoantennaes, and photovoltaics.

Quadrupole-enhanced Raman scattering.

Here we present a label-free method for studying the mechanism of surface effects on amyloid aggregation. In this method, spin-coating is used to rapidly dry samples, in a homogeneous manner, after various incubation times. This technique allows the control of important parameters for self-assembly, such as the surface concentration. Atomic force microscopy is then used to obtain high-resolution images of the morphology. While imaging under dry conditions, we show that the morphologies of self-assembled aggregates of a model amyloid-β peptide, Aβ(12-28), are strongly influenced by the local surface concentration. On mica surfaces, where the peptides can freely diffuse, homogeneous, self-assembled protofibrils formed spontaneously and grew longer with longer subsequent incubation. The surface fibrillization rate was much faster than the rates of fibril formation observed in solution, with initiation occurring at much lower concentrations. These data suggest an alternative pathway for amyloid formation on surfaces where the nucleation stage is either bypassed entirely or too fast to measure. This simple preparation procedure for high-resolution atomic force microscopy imaging of amyloid oligomers and protofibrils should be applicable to any amyloidogenic protein species.

Surface effects mediate self-assembly of amyloid-β peptides.

In this article, we use cooling-rate dependent Tg measurements (CR-Tg) to indirectly probe the relaxation dynamics of supported polystyrene thin films of various molecular weights, all chosen to be above the entanglement molecular weight. We show that the dynamics in these films deviate from bulk dynamics below a temperature T(*) = Tg + 6 K = 380  K ± 1  K. We show that T(*) for films of all thicknesses and molecular weights is the same as the temperature at which the free surface dynamics deviate from the bulk dynamics. The apparent activation barrier of the glass transition in thin films decreases towards that of the free surface as the film thickness decreases. This provides strong evidence that thin film dynamics are facilitated by the enhanced mobility at the free surface. The observation of T(*) can help resolve some seemingly contradictory data by suggesting that studies performed at higher temperatures (T > T(*)), or which probe shorter relaxation times (τ < τ(*) ∼ 1 s) would not observe properties that deviate from bulk values. We also demonstrate that the relaxation dynamics of supported entangled polystyrene films slow down slightly as the molecular weight of polystyrene increases. An eight nanometer film of Mw =2240 kg/mol polystyrene shows a Tg reduction of 27 K at a cooling rate of 1 K/min, while a film of the same thickness made of Mw =45.8 kg/mol polystyrene has a 36 K reduction of Tg compared to the bulk film at the same cooling rate. We hypothesize this is either due to the density of a dynamically "dead" layer near the substrate increasing with molecular weight, or partial anchoring of long chains, which could hinder segmental diffusion near the free surface.

Facilitation of interfacial dynamics in entangled polymer films.

We report a synthetic approach to produce raspberry-like plasmonic nanostructures with unusually strong magnetic resonances, termed raspberry-like metamolecules (raspberry-MMs). The synthesis based on the surfactant-assisted templated seed-growth method allows for the simultaneous one-step synthesis and assembly of well-insulated gold nanoparticles. The aromatic surfactant used for the syntheses forms a thin protective layer around the nanoparticles, preventing them from touching each other and making it possible to pack discrete nanoparticles at close distances in a single cluster. The resulting isotropic gold nanoparticle clusters (i.e., raspberry-MMs) exhibit unusually broad extinction spectra in the visible and near-IR region. Finite-difference time-domain (FDTD) modeling showed that the raspberry-MMs support strong magnetic resonances that contribute significantly to the broadband spectra. The strong magnetic scattering was also verified by far-field scattering measurements, which show that in the near-IR region the magnetic dipole resonance can be even stronger than the electric dipole resonance in these raspberry-MMs. Structural parameters such as the size and the number of gold nanoparticles composing raspberry-MMs can be readily tuned in our synthetic method. A series of syntheses with varying structure parameters, along with FDTD modeling and mode analyses of corresponding model structures, showed that the close packing of a large number of metal nanoparticles in raspberry-MMs is responsible for the unusually strong magnetic resonances observed here.

Raspberry-like metamolecules exhibiting strong magnetic resonances.

Near-field enhancement of the electric field by metallic nanostructures is important in non-linear optical applications such as surface enhanced Raman scattering. One approach to producing strong localization of the electric field is to couple a dark, non-radiating plasmonic mode with a broad dipolar resonator that is detectable in the far-field. However, characterizing or predicting the degree of the coupling between these modes for a complicated nanostructure can be quite challenging. Here we develop a robust method to solve the T-matrix, the matrix that predicts the scattered electric fields of the incident light, based on finite-difference time-domain (FDTD) simulations and least square fitting algorithms. This method allows us to simultaneously calculate the T-matrix for a broad spectral range. Using this method, the coupling between the electric dipole and quadrupole modes of spiky nanoshells is evaluated. It is shown that the built-in disorder in the structure of these nanoshells allows for coupling between the dipole modes of various orientations as well as coupling between the dipole and the quadrupole modes. A coupling strength of about 5% between these modes can explain the apparent interference features observed in the single particle scattering spectrum. This effect is experimentally verified by single particle backscattering measurements of spiky nanoshells. The modal interference in disordered spiky nanoshells can explain the origin of the spectrally broad quadrupole resonances that result in strong Quadrupole Enhanced Raman Scattering (QERS) in these nanoparticles.

Modal interference in spiky nanoshells.

We report the synthesis and characterization of an analogous series of small organic molecules derived from a well-known glass former, 1,3-bis(1-naphthyl)-5-(2-naphthyl)benzene (α,α,β-TNB). Synthesized molecules include α,α,β-TNB, 3,5-di(naphthalen-1-yl)-1-phenylbenzene (α,α-P), 9-(3,5-di(naphthalen-1-yl)phenyl)anthracene (α,α-A), 9,9'-(5-(naphthalen-2-yl)-1,3-phenylene)dianthracene (β-AA) and 3,3',5,5'-tetra(naphthalen-1-yl)-1,1'-biphenyl (α,α,α,α-TNBP). The design of molecules was based on increasing molecular weight with varied π-π interactions in one or more substituents. The synthesis is based on Suzuki cross-coupling of 1-bromo-3-chloro-5-iodobenzene with arylboronic acids, which allows attachment of various substituents to tailor the chemical structure. The bulk compounds were characterized using NMR spectroscopy and differential scanning calorimetry (DSC). Thin films of these compounds were produced using physical vapor deposition and were subsequently annealed above the glass transition temperatures (Tg). For each molecular glass, cooling rate-dependent glass transition temperature measurements (CR-Tg) were performed using ellipsometry as a high-throughput method to characterize thin film properties. CR-Tg allows rapid characterization of glassy properties, such as Tg, apparent thermal expansion coefficients, apparent activation energy at Tg and fragility. DSC measurements confirmed the general trend that increasing molecular weight leads to increasing melting point (Tm) and Tg. Furthermore, CR-Tg provided evidence that the introduction of stronger π-interacting substituents in the chosen set of structural analogues increases fragility and decreases the ability to form glasses, such that β-AA has the largest fragility and highest tendency to crystallize among all the compounds. These strong interactions also significantly elevate Tg and promote more harmonic intermolecular potentials, as observed by decreasing value of the apparent thermal expansion coefficient.

Synthesis and high-throughput characterization of structural analogues of molecular glassformers: 1,3,5-trisarylbenzenes.

We detail the formation and properties associated with stable glasses (SG) formed by a series of structural analogues of 1,3-bis(1-naphthyl)-5-(2-naphthyl)benzene (α,α,β-TNB), a well-studied SG former. Five compounds with similar structural properties were synthesized and physical vapor-deposited with a constant deposition rate at various substrate temperatures (Tdep) in the range between 0.73 Tg and 0.96 Tg. These molecules include α,α,β-TNB, 3,5-di(naphthalen-1-yl)-1-phenylbenzene (α,α-P), 9-(3,5-di(naphthalen-1-yl)phenyl)anthracene (α,α-A), 9,9'-(5-(naphthalen-2-yl)-1,3-phenylene)dianthracene (β-AA), and 3,3',5,5'-tetra(naphthalen-1-yl)-1,1'-biphenyl (α,α,α,α-TNBP). Ellipsometry was used to study the transformations from the as-deposited glasses into ordinary glasses (OG). The stability of each film was evaluated by measuring the fictive temperature (Tf) and density difference between the as-deposited glass and OG. It is demonstrated that all five molecules can form SGs upon vapor deposition in this temperature range. In-depth studies on the dependence of the stability of as-deposited glasses upon Tdep were performed with three molecules, α,α,β-TNB, α,α-P, and α,α-A. The general trends of stability were comparable at the same Tdep/Tg for these three compounds. Similar to previous studies on α,α,β-TNB, vapor-deposited glasses of α,α-P and α,α-A formed the most stable structures around Tdep = 0.8-0.85 Tg. The most stable glass of each molecule showed the lowest thermal expansion coefficient compared to OG and a positive optical birefringence. However, the SGs of α,α-A were less stable compared to α,α-P and α,α,β-TNB at the relative Tdep/Tg. Based on Arrhenius extrapolation of the aging time, as a measure of stability, the most stable α,α-A glass was only aged for a few years as opposed to hundreds or thousands of years for other glasses. We hypothesize that the reduced stability is due to slower mobility at the free surface of α,α-A glass compared to the other two molecules.

Zahra Fakhraai

Department of Chemistry

University of Wisconsin

Assembly, Tuning and Use of an Apertureless Near Field Infrared Microscope for Protein Imaging

Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films

Zahra Fakhraai

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Chemistry

University of Wisconsin

Assembly, Tuning and Use of an Apertureless Near Field Infrared Microscope for Protein Imaging

Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films

Department of Chemistry