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Cellular water can be removed to reversibly inactivate microorganisms to facilitate storage. One such method of removal is freeze-drying, which is ...

Cryo-electron Microscopy Specimen Preparation By Means Of a Focused Ion Beam

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Uppsala University

One of the most challenging issues in the characterization of magnetic materials is to obtain a quantitative analysis on the nanometer scale. Here we describe how electron magnetic circular dichroism (EMCD) measurements using the transmission electron microscope can be used for that purpose, utilizing reciprocal space maps. Applying the EMCD sum rules, an orbital to spin moment ratio of mL/mS=0.08+/-0.01 is obtained for Fe, which is consistent with the commonly accepted value. Hence, we establish EMCD as a quantitative element-specific technique for magnetic studies, using a widely available instrument with superior spatial resolution.

Quantitative magnetic information from reciprocal space maps in transmission electron microscopy.

Calcium phosphate ceramic coatings, applied on surfaces of metallic and polymeric biomaterials, can improve their performance in bone repair and regeneration. Spider silk is biocompatible, strong and elastic, and hence an attractive biomaterial for applications in connective tissue repair. Recently, artificial spider silk, with mechanical and structural characteristics similar to those of native spider silk, has been produced from recombinant minispidroins. In the present study, supersaturated simulated body fluid was used to deposit calcium phosphate coatings on recombinant spider silk fibres. The mineralization process was followed in time using scanning electron microscopy equipped with an energy dispersive x-ray (EDX) detector and Raman spectroscope. Focused ion beam technology was used to produce a cross section of a coated fibre, which was further analysed by EDX. Preliminary in vitro experiments using a culture of bone marrow-derived human mesenchymal stem cells (hMSCs) on coated fibres were also performed. This study showed that recombinant spider silk fibres were successfully coated with a homogeneous and thick crystalline calcium phosphate layer. In the course of the mineralization process from modified simulated body fluid, sodium chloride crystals were first deposited on the silk surface, followed by the deposition of a calcium phosphate layer. The coated silk fibres supported the attachment and growth of hMSCs.

Biomimetic calcium phosphate coatings on recombinant spider silk fibres.

&#x7535;&#x5B50;&#x78C1;&#x6027;&#x7684;&#x624B;&#x6027;&#x4E8C;&#x8272; (EMCD) &#x4E0E;&#x7EB3;&#x7C73;&#x51B3;&#x8BAE;&#x7684;&#x53EF;&#x80FD;&#x6027;&#x662F;&#x5229;&#x7528;&#x900F;&#x5C04;&#x7535;&#x955C; (TEM) &#x78C1;&#x7279;&#x6027;&#x5B9A;&#x91CF;&#x6D4B;&#x91CF;&#x65B0;&#x5174;&#x5DE5;&#x5177;&#x3002;&#x51E0;&#x4F55;&#x6761;&#x4EF6;&#xFF0C;&#x6570;&#x636E;&#x5904;&#x7406;&#x548C;&#x7535;&#x5B50;&#x67AA;&#x8BBE;&#x7F6E;&#x53D1;&#x73B0;&#x5F71;&#x54CD; EMCD &#x4FE1;&#x53F7;&#x3002;&#x5728;&#x672C;&#x6587;&#x4E2D;&#xFF0C;&#x7279;&#x522B;&#x6CE8;&#x610F;&#x662F;&#x91C7;&#x53D6;&#x83B7;&#x5F97;&#x53EF;&#x9760;&#x7684;&#x5B9A;&#x91CF;&#x6D4B;&#x91CF;&#x7684;&#x8F68;&#x9053;&#xFF0C;&#x81EA;&#x65CB;&#x78C1;&#x77E9;&#x4F7F;&#x7528;&#x7B5B;&#x9009;&#x7684;&#x80FD;&#x91CF;&#x884D;&#x5C04;&#x56FE;&#x6848;&#x7684;&#x6BD4;&#x7387;&#x3002;&#x4E3A;&#x6B64;&#x76EE;&#x7684;&#xFF0C;&#x6211;&#x4EEC;&#x63CF;&#x8FF0;&#x4E86;&#x6570;&#x636E;&#x5904;&#x7406;&#x3001; &#x6B63;&#x5E38;&#x5316;&#x548C;&#x955C;&#x50CF;&#x8F74;&#x9009;&#x62E9;&#x4E00;&#x79CD;&#x65B9;&#x6CD5;&#x3002;&#x5B9E;&#x9A8C;&#x7684;&#x7ED3;&#x679C;&#x5F97;&#x5230;&#x4E86;&#x52A8;&#x529B;&#x5B66;&#x884D;&#x5C04;&#x548C;&#x5BC6;&#x5EA6;&#x6CDB;&#x51FD;&#x7406;&#x8BBA;&#x7684;&#x57FA;&#x7840;&#x7684;&#x7406;&#x8BBA;&#x6A21;&#x62DF;&#x3002;&#x7279;&#x522B;&#x8BBE;&#x7F6E;&#x7684;&#x7535;&#x5B50;&#x67AA;&#xFF0C;&#x6240;&#x4EE5;&#x79F0;&#x4E3A; telefocus &#x6A21;&#x5F0F;&#xFF0C;&#x4F7F;&#x8F83;&#x9AD8;&#x5F3A;&#x5EA6;&#x7684;&#x7535;&#x5B50;&#x675F;&#xFF0C;&#x4EE5;&#x53CA;&#x51CF;&#x5C11;&#x5DE5;&#x4EF6;&#x5BF9;&#x4FE1;&#x53F7;&#x7684;&#x5F71;&#x54CD;&#x3002;&#x6211;&#x4EEC;&#x4F7F;&#x7528;&#x8FD9;&#x4E9B;&#x8BBE;&#x7F6E;&#xFF0C;&#x8BC1;&#x660E;&#x83B7;&#x53D6;&#x771F;&#x5B9E;&#x7A7A;&#x95F4;&#x5730;&#x56FE; EMCD &#x4FE1;&#x53F7;&#x7684;&#x539F;&#x5219;&#x3002;&#x8FD9;&#x4F7F;&#x5148;&#x8FDB;&#x7684;&#x8868;&#x5F81;&#x7684;&#x78C1;&#x6027;&#x6750;&#x6599;&#x4E0E;&#x4F18;&#x8D8A;&#x7684;&#x7A7A;&#x95F4;&#x5206;&#x8FA8;&#x7387;&#x3002;

&#x4E92;&#x60E0;&#x548C;&#x771F;&#x5B9E;&#x7A7A;&#x95F4;&#x6620;&#x5C04; EMCD &#x5B9E;&#x9A8C;&#x3002;

Electron magnetic chiral dichroism (EMCD) is an emerging tool for quantitative measurements of magnetic properties using the transmission electron microscope (TEM), with the possibility of nanometer resolution. The geometrical conditions, data treatment and electron gun settings are found to influence the EMCD signal. In this article, particular care is taken to obtain a reliable quantitative measurement of the ratio of orbital to spin magnetic moment using energy filtered diffraction patterns. For this purpose, we describe a method for data treatment, normalization and selection of mirror axis. The experimental results are supported by theoretical simulations based on dynamical diffraction and density functional theory. Special settings of the electron gun, so called telefocus mode, enable a higher intensity of the electron beam, as well as a reduction of the influence from artifacts on the signal. Using these settings, we demonstrate the principle of acquiring real space maps of the EMCD signal. This enables advanced characterization of magnetic materials with superior spatial resolution.

Reciprocal and real space maps for EMCD experiments.

Dichro&iuml;sme chiral magn&eacute;tique d&#39;&eacute;lectrons (EMCD) est un outil &eacute;mergent pour des mesures quantitatives des propri&eacute;t&eacute;s magn&eacute;tiques &agrave; l&#39;aide du microscope &eacute;lectronique &agrave; transmission (TEM), avec la possibilit&eacute; de r&eacute;solution nanom&eacute;trique. Les conditions g&eacute;om&eacute;triques, param&egrave;tres de traitement et de Canon &agrave; &eacute;lectrons de donn&eacute;es sont trouvent &agrave; influencer le signal EMCD. Dans cet article, un soin tout particulier est pris pour obtenir une mesure quantitative fiable du ratio d&#39;orbitale pour filer le moment magn&eacute;tique &agrave; l&#39;aide de la diffraction de l&#39;&eacute;nergie filtr&eacute;. &Agrave; cette fin, nous d&eacute;crivons une m&eacute;thode de traitement de donn&eacute;es, de normalisation et de s&eacute;lection de l&#39;axe du miroir. Les r&eacute;sultats exp&eacute;rimentaux sont pris en charge par des simulations th&eacute;oriques bas&eacute;es sur la diffraction dynamique et la th&eacute;orie fonctionnelle de la densit&eacute;. Param&egrave;tres sp&eacute;ciaux du canon &agrave; &eacute;lectrons, ce qu&#39;on appelle le mode de telefocus, permettent une plus grande intensit&eacute; du faisceau d&#39;&eacute;lectrons, ainsi qu&#39;une r&eacute;duction de l&#39;influence d&#39;artefacts sur le signal. &Agrave; l&#39;aide de ces param&egrave;tres, nous d&eacute;montrons le principe de l&#39;acquisition de cartes de l&#39;espace r&eacute;el du signal EMCD. Cela permet des avanc&eacute;es de caract&eacute;risation des mat&eacute;riaux magn&eacute;tiques avec une r&eacute;solution spatiale sup&eacute;rieure.

Espace r&eacute;ciproque et r&eacute;el des cartes pour EMCD exp&eacute;riences.

Elektron magnetische chirale Dichroismus (EMCD) ist ein aufstrebenden Werkzeug f&uuml;r quantitative Messungen der magnetischen Eigenschaften mithilfe der Transmissions-Elektronenmikroskop (TEM), mit der M&ouml;glichkeit der Nanometer-Aufl&ouml;sung. Die geometrischen Bedingungen, Behandlung und Elektronenkanone Dateneinstellungen festgestellt das EMCD Signal beeinflussen. In diesem Artikel ist besondere Sorgfalt, zuverl&auml;ssige quantitative Messung des Verh&auml;ltnisses von Orbital, magnetisches Moment mit gefiltert Beugung Energiemuster spin zu erhalten. Zu diesem Zweck beschreiben wir eine Methode f&uuml;r die Behandlung der Daten, Normalisierung und Auswahl der Spiegelachse. Die experimentellen Ergebnisse werden durch theoretische Simulationen auf der Grundlage von dynamischen Beugung und Dichtefunktionaltheorie unterst&uuml;tzt. Spezielle Einstellungen f&uuml;r die Elektronenkanone, so genannte Telefocus Modus, erm&ouml;glichen eine h&ouml;here Intensit&auml;t des Elektronenstrahls, sowie eine Reduzierung des Einflusses von Artefakten auf das Signal. Verwenden diese Einstellungen, demonstrieren wir das Prinzip der realen Raum Karten des Signals EMCD zu erwerben. Dadurch erweiterte Charakterisierung von Magnetwerkstoffen mit &uuml;berlegener r&auml;umlicher Aufl&ouml;sung.

Wechselseitige und realer Raum Karten f&uuml;r EMCD Experimente.

Dicroismo chirale magnetico (EMCD) di elettroni &egrave; uno strumento emergente per le misure quantitative delle propriet&agrave; magnetiche utilizzando il microscopio elettronico a trasmissione (TEM), con la possibilit&agrave; di risoluzione nanometrica. Le condizioni geometriche, impostazioni di trattamento e cannone elettronico di dati si trovano ad per influenzare il segnale EMCD. In questo articolo, &egrave; prestare particolare attenzione per ottenere una misurazione quantitativa affidabile del rapporto tra orbitali di spin momento magnetico utilizzando modelli di diffrazione energia filtrata. Per questo scopo, si descrive un metodo per il trattamento dei dati, normalizzazione e selezione dell&#39;asse specchio. I risultati sperimentali sono supportati da simulazioni teorici basati sulla diffrazione dinamici e teoria del funzionale della densit&agrave;. Impostazioni speciali della pistola di elettrone, cos&igrave; chiamato telefocus modalit&agrave;, consentono una maggiore intensit&agrave; del fascio di elettroni, cos&igrave; come una riduzione dell&#39;influenza da artefatti sul segnale. Utilizzando queste impostazioni, dimostriamo il principio di acquisizione di mappe dello spazio reale del segnale EMCD. In questo modo avanzato caratterizzazione di materiali magnetici con risoluzione spaziale superiore.

Spazio reale e reciproco mappe per EMCD esperimenti.

&#x96FB;&#x5B50;&#x78C1;&#x6C17;&#x30AB;&#x30A4;&#x30E9;&#x30EB;&#x4E8C;&#x8272;&#x6027; (EMCD) &#x96FB;&#x5B50;&#x9855;&#x5FAE;&#x93E1; (TEM) &#x306B;&#x3088;&#x308B;&#x78C1;&#x6C17;&#x7279;&#x6027;&#x306E;&#x5B9A;&#x91CF;&#x7684;&#x306A;&#x6E2C;&#x5B9A;&#x306E;&#x305F;&#x3081;&#x306E;&#x65B0;&#x8208;&#x30C4;&#x30FC;&#x30EB;&#x3092;&#x30CA;&#x30CE;&#x30E1;&#x30FC;&#x30C8;&#x30EB;&#x5206;&#x89E3;&#x80FD;&#x306E;&#x53EF;&#x80FD;&#x6027;&#x3067;&#x3059;&#x3002;&#x5E7E;&#x4F55;&#x5B66;&#x7684;&#x6761;&#x4EF6;&#x3001;&#x30C7;&#x30FC;&#x30BF;&#x51E6;&#x7406;&#x30FB;&#x96FB;&#x5B50;&#x9283;&#x8A2D;&#x5B9A;&#x306F; EMCD &#x4FE1;&#x53F7;&#x306B;&#x5F71;&#x97FF;&#x3092;&#x4E0E;&#x3048;&#x308B;&#x3053;&#x3068;&#x306B;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;&#x3053;&#x306E;&#x8A18;&#x4E8B;&#x3067;&#x306F;&#x3001;&#x7279;&#x5B9A;&#x306E;&#x30B1;&#x30A2;&#x306F;&#x30D5;&#x30A3;&#x30EB;&#x30BF;&#x30FC; &#x30A8;&#x30CD;&#x30EB;&#x30AE;&#x30FC;&#x56DE;&#x6298;&#x30D1;&#x30BF;&#x30FC;&#x30F3;&#x3092;&#x7528;&#x3044;&#x305F;&#x78C1;&#x6C17;&#x30E2;&#x30FC;&#x30E1;&#x30F3;&#x30C8;&#x306E;&#x30B9;&#x30D4;&#x30F3;&#x8ECC;&#x9053;&#x306E;&#x6BD4;&#x7387;&#x306E;&#x4FE1;&#x983C;&#x6027;&#x306E;&#x9AD8;&#x3044;&#x5B9A;&#x91CF;&#x7684;&#x6E2C;&#x5B9A;&#x3092;&#x53D6;&#x5F97;&#x3059;&#x308B;&#x64AE;&#x5F71;&#x3067;&#x3059;&#x3002;&#x3053;&#x306E;&#x76EE;&#x7684;&#x306E;&#x305F;&#x3081;&#x306B;&#x3001;&#x30C7;&#x30FC;&#x30BF;&#x51E6;&#x7406;&#x3001;&#x6B63;&#x898F;&#x5316;&#x304A;&#x3088;&#x3073;&#x30DF;&#x30E9;&#x30FC;&#x306E;&#x8EF8;&#x306E;&#x9078;&#x629E;&#x65B9;&#x6CD5;&#x306B;&#x3064;&#x3044;&#x3066;&#x8AAC;&#x660E;&#x3057;&#x307E;&#x3059;&#x3002;&#x5B9F;&#x9A13;&#x306E;&#x7D50;&#x679C;&#x306F;&#x52D5;&#x529B;&#x5B66;&#x56DE;&#x6298;&#x3068;&#x5BC6;&#x5EA6;&#x6C4E;&#x95A2;&#x6570;&#x7406;&#x8AD6;&#x306B;&#x57FA;&#x3065;&#x304F;&#x7406;&#x8AD6;&#x30B7;&#x30DF;&#x30E5;&#x30EC;&#x30FC;&#x30B7;&#x30E7;&#x30F3;&#x306B;&#x3088;&#x3063;&#x3066;&#x30B5;&#x30DD;&#x30FC;&#x30C8;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002;&#x96FB;&#x5B50;&#x9283;&#x306E;&#x7279;&#x5225;&#x306A;&#x8A2D;&#x5B9A;&#x306F;&#x3001;&#x3060;&#x304B;&#x3089; telefocus &#x30E2;&#x30FC;&#x30C9;&#x3068;&#x547C;&#x3070;&#x308C;&#x308B;&#x3001;&#x96FB;&#x5B50;&#x30D3;&#x30FC;&#x30E0;&#x306E;&#x9AD8;&#x5F37;&#x5EA6;&#x3060;&#x3051;&#x3067;&#x306A;&#x304F;&#x3001;&#x4FE1;&#x53F7;&#x306F;&#x3001;&#x6210;&#x679C;&#x7269;&#x304B;&#x3089;&#x306E;&#x5F71;&#x97FF;&#x306E;&#x524A;&#x6E1B;&#x3092;&#x6709;&#x52B9;&#x306B;&#x3057;&#x307E;&#x3059;&#x3002;&#x3053;&#x308C;&#x3089;&#x306E;&#x8A2D;&#x5B9A;&#x3092;&#x4F7F;&#x7528;&#x3057;&#x3066;&#x3001;EMCD &#x4FE1;&#x53F7;&#x306E;&#x5B9F;&#x7A7A;&#x9593;&#x30DE;&#x30C3;&#x30D7;&#x3092;&#x53D6;&#x5F97;&#x3059;&#x308B;&#x539F;&#x7406;&#x3092;&#x793A;&#x3057;&#x307E;&#x3059;&#x3002;&#x3053;&#x308C;&#x306F;&#x512A;&#x308C;&#x305F;&#x7A7A;&#x9593;&#x5206;&#x89E3;&#x80FD;&#x78C1;&#x6027;&#x6750;&#x6599;&#x306E;&#x9AD8;&#x5EA6;&#x306A;&#x8A55;&#x4FA1;&#x3092;&#x3067;&#x304D;&#x307E;&#x3059;&#x3002;

&#x76F8;&#x4E92;&#x30FB;&#x5B9F;&#x7A7A;&#x9593; EMCD &#x5B9F;&#x9A13;&#x3092;&#x30DE;&#x30C3;&#x30D7;&#x3057;&#x307E;&#x3059;&#x3002;

&#xC804;&#xC790; &#xB9C8;&#xADF8;&#xB124;&#xD2F1; &#xD0A4; &#xB784; &#xC591;&#xC0C9;&#xC131; (EMCD) &#xAC00;&#xB2A5;&#xC131;&#xC744; &#xB098;&#xB178;&#xBBF8;&#xD130; &#xBD84;&#xD574;&#xB2A5; &#xC804;&#xC1A1; &#xC804;&#xC790; &#xD604;&#xBBF8;&#xACBD; (TEM)&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xC790;&#xAE30; &#xD2B9;&#xC131;&#xC758; &#xC815;&#xB7C9;&#xC801; &#xCE21;&#xC815;&#xC744; &#xC704;&#xD55C; &#xC0C8;&#xB85C;&#xC6B4; &#xB3C4;&#xAD6C;&#xC785;&#xB2C8;&#xB2E4;. &#xAE30;&#xD558;&#xD559;&#xC801; &#xC870;&#xAC74; &#xB370;&#xC774;&#xD130; &#xCC98;&#xB9AC; &#xBC0F; &#xC804;&#xC790; &#xCD1D; &#xC124;&#xC815; EMCD &#xC2E0;&#xD638;&#xC5D0; &#xC601;&#xD5A5;&#xC744; &#xCC3E;&#xC744; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;. &#xC774; &#xBB38;&#xC11C;&#xC5D0;&#xC11C;&#xB294; &#xD2B9;&#xC815; &#xC8FC;&#xC758; &#xC5D0;&#xB108;&#xC9C0; &#xD544;&#xD130;&#xB9C1; &#xB41C; &#xD68C;&#xC808; &#xD328;&#xD134;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xC790;&#xAE30; &#xBAA8;&#xBA58;&#xD2B8; &#xC2A4;&#xD540; &#xADA4;&#xB3C4; &#xBE44;&#xC728;&#xC758; &#xC2E0;&#xB8B0;&#xD560; &#xC218; &#xC788;&#xB294; &#xC815;&#xB7C9;&#xC801; &#xCE21;&#xC815; &#xD558;&#xB824;&#xBA74;. &#xC774; &#xC704;&#xD574; &#xB370;&#xC774;&#xD130; &#xCC98;&#xB9AC;, &#xD45C;&#xC900;&#xD654; &#xBC0F; &#xBBF8;&#xB7EC; &#xCD95; &#xC911; &#xD558;&#xB098;&#xB97C; &#xC120;&#xD0DD; &#xD558;&#xB294; &#xBC29;&#xBC95;&#xC744; &#xC124;&#xBA85;&#xD569;&#xB2C8;&#xB2E4;. &#xC2E4;&#xD5D8; &#xACB0;&#xACFC; &#xC5ED; &#xB3D9; &#xD68C;&#xC808; &#xBC0F; &#xBC00;&#xB3C4; &#xAE30;&#xB2A5; &#xC774;&#xB860;&#xC5D0; &#xAE30;&#xBC18; &#xD558;&#xB294; &#xC774;&#xB860;&#xC801; &#xC2DC;&#xBBAC;&#xB808;&#xC774;&#xC158;&#xC5D0; &#xC758;&#xD574; &#xC9C0;&#xC6D0; &#xB429;&#xB2C8;&#xB2E4;. &#xC804;&#xC790; &#xCD1D;&#xC758; &#xD2B9;&#xBCC4; &#xD55C; &#xC124;&#xC815;&#xC744; &#xC18C;&#xC704; telefocus &#xBAA8;&#xB4DC;, &#xC804;&#xC790; &#xBE54;&#xC758; &#xB192;&#xC740; &#xAC15;&#xB3C4; &#xBFD0;&#xB9CC; &#xC544;&#xB2C8;&#xB77C; &#xC2E0;&#xD638;&#xC5D0; &#xBD88;&#xD544;&#xC694; &#xD55C; &#xC601;&#xD5A5;&#xC758; &#xAC10;&#xC18C;&#xB97C; &#xC0AC;&#xC6A9; &#xD558;&#xB3C4;&#xB85D; &#xC124;&#xC815; &#xD569;&#xB2C8;&#xB2E4;. &#xC774;&#xB7EC;&#xD55C; &#xC124;&#xC815;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC;, &#xC6B0;&#xB9AC; EMCD &#xC2E0;&#xD638;&#xC758; &#xC2E4;&#xC81C; &#xACF5;&#xAC04; &#xC9C0;&#xB3C4; &#xD68D;&#xB4DD; &#xD558;&#xB294; &#xC6D0;&#xCE59;&#xC744; &#xBCF4;&#xC5EC; &#xC90D;&#xB2C8;&#xB2E4;. &#xC6B0;&#xC218;&#xD55C; &#xACF5;&#xAC04; &#xD574;&#xC0C1;&#xB3C4;&#xC640; &#xC790;&#xC131; &#xC7AC;&#xB8CC;&#xC758; &#xACE0;&#xAE09; &#xD2B9;&#xC131;&#xC744; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;.

&#xC0C1;&#xD638;&#xC640; &#xC2E4;&#xC81C; &#xACF5;&#xAC04; EMCD &#xC2E4;&#xD5D8;&#xC5D0; &#xB300; &#xD55C; &#xC9C0;&#xB3C4;.

Dicro&iacute;smo quiral magn&eacute;tico de electr&oacute;n (EMCD) es una herramienta emergente para mediciones cuantitativas de propiedades magn&eacute;ticas utilizando el microscopio electr&oacute;nico de transmisi&oacute;n (TEM), con la posibilidad de resoluci&oacute;n del nan&oacute;metro. Las condiciones geom&eacute;tricas, configuraci&oacute;n de datos tratamiento y arma de electr&oacute;n se encuentra para influir en la se&ntilde;al EMCD. En este art&iacute;culo, se toma especial cuidado para obtener una medida cuantitativa fiable de la relaci&oacute;n de orbital al momento magn&eacute;tico, utilizando patrones de difracci&oacute;n de energ&iacute;a filtrada de la vuelta. Para ello, se describe un m&eacute;todo para el tratamiento de los datos, la normalizaci&oacute;n y la selecci&oacute;n del eje del espejo. Los resultados experimentales son apoyados por simulaciones te&oacute;ricas basadas en la difracci&oacute;n din&aacute;mico y la teor&iacute;a funcional de la densidad. Ajustes especiales de la arma de electr&oacute;n, denominados telefocus modo, permiten una mayor intensidad de los haces de electrones, as&iacute; como una reducci&oacute;n de la influencia de los artefactos en la se&ntilde;al. Estos par&aacute;metros, demostramos el principio de adquirir mapas de espacio real de la se&ntilde;al EMCD. Esto permite caracterizaci&oacute;n avanzada de materiales magn&eacute;ticos con resoluci&oacute;n espacial superior.

Espacio rec&iacute;proco y real los mapas EMCD experimentos.

The present work provides the first real-space analysis of nanobead-DNA coil interactions. Immobilization of oligonucleotide-functionalized magnetic nanobeads in rolling circle amplified DNA-coils was studied by complex magnetization measurements and transmission electron microscopy (TEM), and a statistical analysis of the number of beads hybridized to the DNA-coils was performed. The average number of beads per DNA-coil using the results from both methods was found to be around 6 and slightly above 2 for samples with 40 and 130 nm beads, respectively. The TEM analysis supported an earlier hypothesis that 40 nm beads are preferably immobilized in the interior of DNA-coils whereas 130 nm beads, to a larger extent, are immobilized closer to the exterior of the coils. The methodology demonstrated in the present work should open up new possibilities for characterization of interactions of a large variety of functionalized nanoparticles with macromolecules, useful for gaining more fundamental understanding of such interactions as well as for optimizing a number of biosensor applications.

Real-space transmission electron microscopy investigations of attachment of functionalized magnetic nanoparticles to DNA-coils acting as a biosensor.

&#x80FD;&#x91CF;&#x8FC7;&#x6EE4;&#x900F;&#x5C04;&#x7535;&#x955C; (EFTEM) &#x6280;&#x672F;&#x5DF2;&#x88AB;&#x7528;&#x6765;&#x7814;&#x7A76;&#x5728;&#x5BFC;&#x7535;&#x9AD8;&#x5206;&#x5B50;&#x590D;&#x5408;&#x7EB3;&#x7C73;&#x7EA4;&#x7EF4;&#x79BB;&#x5B50;&#x4EA4;&#x6362;&#x8FC7;&#x7A0B;&#x3002;&#x78B3;&#x3001; &#x6C2E;&#x3001; &#x6C27;&#x3001; &#x6C2F;&#x3001; &#x787C;&#x3001; &#x78F7;&#x3001; &#x94BC;&#x3001; &#x786B;&#x805A;&#x5421;&#x54AF;&#x7EA4;&#x7EF4;&#x7D20;&#x7EB3;&#x7C73;&#x7EA4;&#x7EF4;&#xFF0C;&#x7528;&#x4F5C;&#x6F5C;&#x529B;&#x63A7;&#x5236;&#x7535;&#x5316;&#x5B66;&#x56FA;&#x76F8;&#x63D0;&#x53D6;&#x5A92;&#x4F53;&#x5185;&#x7684;&#x5143;&#x7D20;&#x5206;&#x5E03;&#x4EA6;&#x66FE;&#x7531; EFTEM&#x3002;&#x805A;&#x5421;&#x54AF;&#x7EA4;&#x7EF4;&#x7D20;&#x7EB3;&#x7C73;&#x7EA4;&#x7EF4;&#x5185;&#x79BB;&#x5B50;&#x7684;&#x5206;&#x5E03;&#x548C;&#x7A7F;&#x900F;&#x6DF1;&#x5EA6;&#x7684;&#x79BB;&#x5B50;&#x8FDB;&#x5165;&#x5927;&#x5C0F;&#x7684;&#x51FD;&#x6570;&#x548C;&#x6536;&#x8D39;&#x7684;&#x540E;&#x8005;&#x4F5C;&#x4E3A;&#x6750;&#x6599;&#x8FDB;&#x884C;&#x4E86;&#x8C03;&#x67E5;&#x3002;&#x8FDB;&#x4E00;&#x6B65;&#xFF0C;&#x7A7A;&#x95F4;&#x5206;&#x5E03;&#x7684;&#x805A;&#x5421;&#x54AF;&#x7EA4;&#x7EF4;&#x7D20;&#x7EB3;&#x7C73;&#x7EA4;&#x7EF4;&#x5185;&#x5355;&#x7EDE; DNA hexamers &#x88AB;&#x6620;&#x5C04;&#x540E;&#x7684; DNA &#x7535;&#x5316;&#x5B66;&#x63A7;&#x5236;&#x63D0;&#x53D6;&#x787C;&#x9178;&#x76D0;&#x7F13;&#x51B2;&#x6EB6;&#x6DB2;&#x3002;&#x8C03;&#x67E5;&#x7ED3;&#x679C;&#x663E;&#x793A; EFTEM &#x6D4B;&#x7ED8;&#x6280;&#x672F; unpreceded &#x4E3A;&#x63D0;&#x4F9B;&#x4E86;&#x53EF;&#x80FD;&#x6027;&#x7684;&#x5185;&#x90E8;&#x5BFC;&#x7535;&#x9AD8;&#x5206;&#x5B50;&#x590D;&#x5408;&#x6750;&#x6599;&#x79BB;&#x5B50;&#x5206;&#x5E03;&#x7684;&#x7814;&#x7A76;&#x3002;

&#x805A;&#x5421;&#x54AF;&#x7EA4;&#x7EF4;&#x7D20;&#x7EB3;&#x7C73;&#x7EA4;&#x7EF4;&#x4F7F;&#x7528;&#x80FD;&#x91CF;&#x8FC7;&#x6EE4;&#x900F;&#x5C04;&#x7535;&#x5B50;&#x663E;&#x5FAE;&#x955C;&#x4E2D;&#x7684;&#x5143;&#x7D20;&#x5206;&#x5E03;&#x7684;&#x7A7A;&#x95F4;&#x6620;&#x5C04;&#x3002;

The energy-filtered transmission electron microscopy (EFTEM) technique has been used to study ion-exchange processes in conductive polymer composite nanofibers. The elemental distributions of carbon, nitrogen, oxygen, chlorine, boron, phosphorus, molybdenum, and sulfur within polypyrrole-cellulose nanofibers, used as potential controlled electrochemical solid phase extraction media, have been studied by EFTEM. The distribution of ions within the polypyrrole-cellulose nanofibers and the penetration depth of ions into the material as a function of the size and charge of the latter were investigated. Further, the spatial distribution of single stranded DNA hexamers inside polypyrrole-cellulose nanofibers was mapped subsequent to the electrochemically controlled extraction of DNA from a borate buffer solution. The results show that the EFTEM mapping technique provides unpreceded possibilities for studies of the distribution of ions inside conductive polymer composites.

Spatial mapping of elemental distributions in polypyrrole-cellulose nanofibers using energy-filtered transmission electron microscopy.

La technique de microscopie &eacute;lectronique (EFTEM) de transmission d&#39;&eacute;nergie filtr&eacute;e a &eacute;t&eacute; utilis&eacute;e pour &eacute;tudier les processus d&#39;&eacute;change d&#39;ions en nanofibres composite polym&egrave;re conducteur. Les distributions &eacute;l&eacute;mentaires de carbone, azote, oxyg&egrave;ne, chlore, bore, phosphore, molybd&egrave;ne et soufre dans des nanofibres de polypyrrole-cellulose, utilis&eacute;es comme potentiel limit&eacute; de m&eacute;dias d&#39;extraction en phase solide &eacute;lectrochimique, ont &eacute;t&eacute; &eacute;tudi&eacute;es par EFTEM. La distribution des ions dans les nanofibres cellulosiques polypyrrole et la profondeur de la p&eacute;n&eacute;tration des ions dans le mat&eacute;riau en fonction de la taille et les frais de ce dernier ont &eacute;t&eacute; &eacute;tudi&eacute;s. En outre, la r&eacute;partition spatiale des simple brin ADN hexam&egrave;res &agrave; l&#39;int&eacute;rieur des nanofibres de polypyrrole-cellulose a &eacute;t&eacute; localis&eacute;e &agrave; la suite de l&#39;extraction par voie &eacute;lectrochimique contr&ocirc;l&eacute;e de l&#39;ADN d&#39;une solution tampon de borate. Les r&eacute;sultats montrent que la technique de cartographie EFTEM fournit des possibilit&eacute;s unpreceded pour l&#39;&eacute;tude de la distribution des ions &agrave; l&#39;int&eacute;rieur des composites polym&egrave;res conducteurs.

Cartographie spatiale des distributions &eacute;l&eacute;mentaires en nanofibres de polypyrrole-cellulose &agrave; l&#39;aide de la microscopie &eacute;lectronique &agrave; transmission &eacute;nerg&eacute;tique filtr&eacute;.

Die Elektronenmikroskopie (EFTEM) &Uuml;bertragungstechnik Energie-gefiltert ist verwendet worden, Ionenaustausch Prozesse in leitf&auml;higen Polymer zusammengesetzte Nanofasern zu studieren. Die elementaren-Distributionen von Kohlenstoff, Stickstoff, Sauerstoff, Chlor, Bor, Phosphor, Molybd&auml;n und Schwefel innerhalb Polypyrrol-Cellulose-Nanofasern, verwendet als Potenzial elektrochemische Festphasen-Extraktion-Medien, beherrscht wurden von EFTEM untersucht. Die Verteilung der Ionen innerhalb der Polypyrrol-Cellulose-Nanofasern und die Eindringtiefe der Ionen in das Material als eine Funktion der Gr&ouml;&szlig;e und Ladung der letzteren wurden untersucht. Des weiteren wurde die r&auml;umliche Verteilung der einzelne angeschwemmte DNA Hexamers innen Polypyrrol-Cellulose-Nanofasern im Anschluss an die Elektrochemisch gesteuerte Extraktion von DNA aus einer Pufferl&ouml;sung Borat zugeordnet. Die Ergebnisse zeigen, dass die EFTEM-Zuordnung-Technik unpreceded M&ouml;glichkeiten f&uuml;r Studien der Verteilung von Ionen in leitf&auml;higen Polymer Composites bietet.

R&auml;umliche Zuordnung von Elementarwesen Verteilungen in Polypyrrol-Cellulose-Nanofasern mit Energie-gefiltert Transmissionselektronenmikroskopie.

La tecnica di microscopia elettronica (EFTEM) trasmissione filtrati energetiche &egrave; stata utilizzata per studiare i processi di scambio ionico in nanofibre compositi polimero conduttivo. Le distribuzioni elementali di carbonio, azoto, ossigeno, cloro, boro, fosforo, molibdeno e zolfo entro le nanofibre di polipirrolo-cellulosa, utilizzate come potenziale controllato media estrazione in fase solida elettrochimico, sono state studiate da EFTEM. La distribuzione degli ioni all&#39;interno le nanofibre di polipirrolo-cellulosa e la profondit&agrave; di penetrazione degli ioni nel materiale in funzione della dimensione e carica di quest&#39;ultimo sono stati studiati. Ulteriormente, &egrave; stata mappata la distribuzione spaziale dei single stranded DNA esameri all&#39;interno di nanofibre di polipirrolo-cellulosa successivamente elettrochimicamente controllata estrazione di DNA da una soluzione tampone borato. I risultati mostrano che la tecnica di mappatura EFTEM prevede la possibilit&agrave; di unpreceded per gli studi della distribuzione degli ioni all&#39;interno di materiali compositi polimero conduttivo.

Mappatura spaziale delle distribuzioni elementali in nanofibre di polipirrolo-cellulosa mediante microscopia elettronica della trasmissione di energia filtrata.

&#x5C0E;&#x96FB;&#x6027;&#x9AD8;&#x5206;&#x5B50;&#x8907;&#x5408;&#x30CA;&#x30CE;&#x30D5;&#x30A1;&#x30A4;&#x30D0;&#x30FC;&#x306E;&#x30A4;&#x30AA;&#x30F3;&#x4EA4;&#x63DB;&#x30D7;&#x30ED;&#x30BB;&#x30B9;&#x3092;&#x7814;&#x7A76;&#x3059;&#x308B;&#x30A8;&#x30CD;&#x30EB;&#x30AE;&#x30FC; &#x30D5;&#x30A3;&#x30EB;&#x30BF;&#x30FC;&#x96FB;&#x5B50;&#x9855;&#x5FAE;&#x93E1; (&#x900F;&#x904E;) &#x6280;&#x8853;&#x304C;&#x4F7F;&#x7528;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x5143;&#x7D20;&#x5206;&#x5E03;&#x306E;&#x70AD;&#x7D20;&#x3001;&#x7A92;&#x7D20;&#x3001;&#x9178;&#x7D20;&#x3001;&#x5869;&#x7D20;&#x3001;&#x30DB;&#x30A6;&#x7D20;&#x3001;&#x30EA;&#x30F3;, &#x30E2;&#x30EA;&#x30D6;&#x30C7;&#x30F3;, &#x786B;&#x9EC4;&#x30DD;&#x30C6;&#x30F3;&#x30B7;&#x30E3;&#x30EB;&#x5236;&#x5FA1;&#x96FB;&#x6C17;&#x5316;&#x5B66;&#x306E;&#x56FA;&#x76F8;&#x62BD;&#x51FA;&#x5A92;&#x4F53;&#x3068;&#x3057;&#x3066;&#x4F7F;&#x7528;&#x3001;&#x30DD;&#x30EA;&#x30D4;&#x30ED;&#x30FC;&#x30EB; &#x30BB;&#x30EB;&#x30ED;&#x30FC;&#x30B9; &#x30CA;&#x30CE;&#x30D5;&#x30A1;&#x30A4;&#x30D0;&#x30FC;&#x5185;&#x900F;&#x904E;&#x306B;&#x3088;&#x3063;&#x3066;&#x7814;&#x7A76;&#x3055;&#x308C;&#x3066;&#x3044;&#x308B;.&#x30DD;&#x30EA;&#x30D4;&#x30ED;&#x30FC;&#x30EB; &#x30BB;&#x30EB;&#x30ED;&#x30FC;&#x30B9; &#x30CA;&#x30CE;&#x30D5;&#x30A1;&#x30A4;&#x30D0;&#x30FC;&#x5185;&#x30A4;&#x30AA;&#x30F3;&#x5206;&#x5E03;&#x306B;&#x5F8C;&#x8005;&#x306E;&#x96FB;&#x8377;&#x3068;&#x30B5;&#x30A4;&#x30BA;&#x306E;&#x95A2;&#x6570;&#x3068;&#x3057;&#x3066;&#x6750;&#x6599;&#x306E;&#x30A4;&#x30AA;&#x30F3;&#x306E;&#x6D78;&#x900F;&#x6DF1;&#x3055;&#x3092;&#x691C;&#x8A0E;&#x3057;&#x305F;.&#x3055;&#x3089;&#x306B;&#x3001;&#x5358;&#x4E00;&#x306E;&#x5B64;&#x7ACB;&#x3057;&#x305F; DNA hexamers &#x30DD;&#x30EA;&#x30D4;&#x30ED;&#x30FC;&#x30EB; &#x30BB;&#x30EB;&#x30ED;&#x30FC;&#x30B9; &#x30CA;&#x30CE;&#x30D5;&#x30A1;&#x30A4;&#x30D0;&#x30FC;&#x306E;&#x5185;&#x5074;&#x306E;&#x7A7A;&#x9593;&#x5206;&#x5E03;&#x306F;&#x30DB;&#x30A6;&#x9178;&#x7DE9;&#x885D;&#x6DB2;&#x304B;&#x3089;&#x306E; DNA &#x306E;&#x96FB;&#x6C17;&#x5316;&#x5B66;&#x7684;&#x306B;&#x5236;&#x5FA1;&#x3055;&#x308C;&#x305F;&#x62BD;&#x51FA;&#x5F8C;&#x306B;&#x30DE;&#x30C3;&#x30D7;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;&#x900F;&#x904E;&#x30DE;&#x30C3;&#x30D4;&#x30F3;&#x30B0;&#x6280;&#x8853;&#x306E;&#x30A4;&#x30AA;&#x30F3;&#x5C0E;&#x96FB;&#x6027;&#x9AD8;&#x5206;&#x5B50;&#x8907;&#x5408;&#x4F53;&#x4E2D;&#x306E;&#x5206;&#x5E03;&#x306E;&#x7814;&#x7A76;&#x306E;&#x305F;&#x3081;&#x306E; unpreceded &#x306E;&#x53EF;&#x80FD;&#x6027;&#x3092;&#x63D0;&#x4F9B;&#x3059;&#x308B;&#x3053;&#x3068;&#x304C;&#x793A;&#x5506;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;

&#x30A8;&#x30CD;&#x30EB;&#x30AE;&#x30FC; &#x30D5;&#x30A3;&#x30EB;&#x30BF;&#x30FC;&#x96FB;&#x5B50;&#x9855;&#x5FAE;&#x93E1;&#x3092;&#x7528;&#x3044;&#x305F;&#x30DD;&#x30EA;&#x30D4;&#x30ED;&#x30FC;&#x30EB; &#x30BB;&#x30EB;&#x30ED;&#x30FC;&#x30B9; &#x30CA;&#x30CE;&#x30D5;&#x30A1;&#x30A4;&#x30D0;&#x30FC;&#x306B;&#x304A;&#x3051;&#x308B;&#x5143;&#x7D20;&#x5206;&#x5E03;&#x306E;&#x7A7A;&#x9593;&#x30DE;&#x30C3;&#x30D4;&#x30F3;&#x30B0;&#x3002;

&#xC804;&#xB3C4;&#xC131; &#xACE0;&#xBD84;&#xC790; &#xD569;&#xC131; nanofibers&#xC5D0;&#xC11C; &#xC774;&#xC628; &#xAD50;&#xD658; &#xACFC;&#xC815;&#xC744; &#xACF5;&#xBD80; &#xC5D0;&#xB108;&#xC9C0; &#xD544;&#xD130;&#xB9C1; &#xC804;&#xC1A1; &#xC804;&#xC790; &#xD604;&#xBBF8;&#xACBD; &#xAC80;&#xC0AC; &#xBC95; (EFTEM) &#xAE30;&#xC220;&#xC744; &#xC0AC;&#xC6A9; &#xB418;&#xC5C8;&#xC2B5;&#xB2C8;&#xB2E4;. &#xD0C4;&#xC18C;, &#xC9C8;&#xC18C;, &#xC0B0;&#xC18C;, &#xC5FC;&#xC18C;, &#xBD95; &#xC18C;, &#xC778;, &#xBAB0; &#xB9AC;&#xBE0C; &#xB374;, &#xBC0F; polypyrrole &#xC140; &#xB8F0; &#xB85C;&#xC2A4; nanofibers, &#xC7A0;&#xC7AC;&#xC801;&#xC778; &#xC81C;&#xC5B4; &#xC804;&#xAE30; &#xD654;&#xD559; &#xACE0;&#xCCB4; &#xB2E8;&#xACC4; &#xCD94;&#xCD9C; &#xBBF8;&#xB514;&#xC5B4;&#xB85C; &#xC0AC;&#xC6A9; &#xB418;&#xB294; &#xB0B4;&#xC5D0;&#xC11C; &#xC720;&#xD669;&#xC758; &#xC6D0;&#xC18C; &#xBD84;&#xD3EC;&#xB294; EFTEM&#xB85C; &#xACF5;&#xBD80; &#xD588;&#xC2B5;&#xB2C8;&#xB2E4;. Polypyrrole-&#xC140; &#xB8F0; &#xB85C;&#xC2A4; nanofibers &#xB0B4;&#xC5D0;&#xC11C; &#xC774;&#xC628;&#xC758; &#xBD84;&#xD3EC;&#xC640; &#xD06C;&#xAE30;&#xC758; &#xD568;&#xC218;&#xC640; &#xD6C4;&#xC790;&#xC758; &#xC694;&#xAE08;&#xC73C;&#xB85C; &#xC18C;&#xC7AC;&#xC5D0; &#xC774;&#xC628;&#xC758; &#xCE68;&#xD22C; &#xAE4A;&#xC774; &#xC870;&#xC0AC; &#xD588;&#xB2E4;. &#xB610;&#xD55C;, &#xB2E8;&#xC77C; &#xC88C;&#xCD08; DNA hexamers polypyrrole-&#xC140; &#xB8F0; &#xB85C;&#xC2A4; nanofibers &#xB0B4;&#xBD80; &#xACF5;&#xAC04; &#xBD84;&#xD3EC; borate &#xBC84;&#xD37C; &#xC194;&#xB8E8;&#xC158;&#xC5D0;&#xC11C; DNA&#xC758; &#xD654;&#xD559;&#xC801; &#xC81C;&#xC5B4; &#xCD94;&#xCD9C; &#xD6C4; &#xB9E4;&#xD551;&#xB41C;. &#xACB0;&#xACFC; EFTEM &#xB9E4;&#xD551; &#xAE30;&#xC220;&#xC740; &#xC804;&#xB3C4;&#xC131; &#xACE0;&#xBD84;&#xC790; &#xBCF5;&#xD569; &#xC7AC;&#xB8CC; &#xB0B4;&#xBD80; &#xC774;&#xC628;&#xC758; &#xBD84;&#xD3EC;&#xC758; &#xC5F0;&#xAD6C; unpreceded &#xAC00;&#xB2A5;&#xC131;&#xC744; &#xC81C;&#xACF5; &#xD569;&#xB2C8;&#xB2E4;.

Polypyrrole-&#xC140; &#xB8F0; &#xB85C;&#xC2A4; nanofibers &#xC5D0;&#xB108;&#xC9C0; &#xD544;&#xD130;&#xB9C1; &#xC804;&#xC1A1; &#xC804;&#xC790; &#xD604;&#xBBF8;&#xACBD; &#xAC80;&#xC0AC; &#xBC95;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xC6D0;&#xC18C; &#xBD84;&#xD3EC;&#xC758; &#xACF5;&#xAC04;&#xC801; &#xB9E4;&#xD551;.

La t&eacute;cnica de microscop&iacute;a electr&oacute;nica (EFTEM) de transmisi&oacute;n de energ&iacute;a filtrada se ha utilizado para estudiar los procesos de intercambio i&oacute;nico en nanofibras compuesto de pol&iacute;mero conductor. Las distribuciones elementales de carbono, nitr&oacute;geno, ox&iacute;geno, cloro, boro, f&oacute;sforo, molibdeno y azufre dentro de polypyrrole-celulosa nanofibras, utilizado como potencial hab&iacute;a controlado por medios de la extracci&oacute;n de fase s&oacute;lida electroqu&iacute;mica, han sido estudiadas por EFTEM. La distribuci&oacute;n de iones dentro de las nanofibras polypyrrole-celulosa y la profundidad de la penetraci&oacute;n de iones en el material como una funci&oacute;n del tama&ntilde;o y la carga de estos &uacute;ltimos fueron investigados. Adem&aacute;s, la distribuci&oacute;n espacial de solo hexamers trenzado de ADN dentro de polypyrrole-celulosa nanofibras fue trazada con posterioridad a la extracci&oacute;n electroqu&iacute;micamente controlada de ADN de un tamp&oacute;n de borato. Los resultados muestran que la t&eacute;cnica de mapeo de EFTEM proporciona posibilidades unpreceded de estudios de la distribuci&oacute;n de iones dentro de los compuestos del pol&iacute;mero conductor.

Asignaci&oacute;n espacial de distribuciones elementales en nanofibras de polypyrrole-celulosa utilizando microscop&iacute;a electr&oacute;nica de transmisi&oacute;n de energ&iacute;a filtrada.

&#x53CC;&#x7CD6;&#x662F;&#xFF0C;&#x4E00;&#x822C;&#x60C5;&#x51B5;&#x4E0B;&#xFF0C;&#x4F5C;&#x4E3A;&#x5236;&#x8BA2;&#x7684;&#x7B2C;&#x4E00;&#x9009;&#x62E9;&#x5316;&#x5408;&#x7269;&#x65F6;&#x51B7;&#x51BB;&#x5E72;&#x71E5;&#x5FAE;&#x751F;&#x7269;&#x3002;&#x867D;&#x7136;&#x548C;&#x5176;&#x4ED6;&#x751F;&#x7269;&#x5927;&#x5206;&#x5B50;&#x591A;&#x7CD6;&#x88AB;&#x8BA4;&#x4E3A;&#x592A;&#x5927;&#xFF0C;&#x7A33;&#x5B9A;&#x548C;&#x53CC;&#x7CD6;&#x76F8;&#x540C;&#x7684;&#x6709;&#x76CA;&#x65B9;&#x5F0F;&#x4E0E;&#x7535;&#x6C60;&#x7EC4;&#x4EF6;&#x7684;&#x4EA4;&#x4E92;&#xFF0C;&#x5DF2;&#x62A5;&#x544A;&#x805A;&#x5408;&#x7269;&#x652F;&#x6301;&#x7EC6;&#x80DE;&#x5B58;&#x6D3B;&#x3002;&#x5728;&#x672C;&#x7814;&#x7A76;&#x4E2D;&#x6211;&#x4EEC;&#x6BD4;&#x8F83;&#x8517;&#x7CD6;&#x548C; Ficoll&#x3001; &#x7F9F;&#x4E59;&#x57FA;&#x3001; hydroxypropylmethylcellulose &#x548C;&#x805A;&#x4E59;&#x70EF;&#x652F;&#x6301;&#x751F;&#x5B58;&#x671F;&#x95F4;&#x4E09;&#x682A;&#x7EC6;&#x83CC;&#x7684;&#x51B7;&#x51BB;&#x5E72;&#x71E5;&#x7684;&#x805A;&#x5408;&#x7269;&#x7684;&#x6548;&#x7387;&#x3002;&#x521D;&#x59CB;&#x6E17;&#x900F;&#x6761;&#x4EF6;&#x88AB;&#x8C03;&#x6574;&#x4E3A;&#x7C7B;&#x4F3C;&#x6240;&#x6709;&#x5236;&#x5242;&#x3002;&#x5236;&#x5B9A;&#x4F20;&#x9500;&#x88AB;&#x7528;&#x6765;&#x89E3;&#x91CA;&#x4E0D;&#x540C;&#x7684;&#x5316;&#x5408;&#x7269;&#x6027;&#x8D28;&#x5BF9;&#x7EC6;&#x80DE;&#x5B58;&#x6D3B;&#x7684;&#x5F71;&#x54CD;&#x3002;

&#x77E9;&#x9635;&#x5C5E;&#x6027;&#x4E0A;&#x7684;&#x51BB;&#x5E72;&#x7EC6;&#x83CC;&#x751F;&#x5B58;&#x7684;&#x5F71;&#x54CD;&#x3002;

Disaccharides are, in general, the first choice as formulation compounds when freeze-drying microorganisms. Although polysaccharides and other biopolymers are considered too large to stabilise and interact with cell components in the same beneficial way as disaccharides, polymers have been reported to support cell survival. In the present study we compare the efficiency of sucrose and the polymers Ficoll, hydroxyethylcellulose, hydroxypropylmethylcellulose and polyvinylalcohol to support the survival of three bacterial strains during freeze drying. The initial osmotic conditions were adjusted to be similar for all formulations. Formulation characterisation was used to interpret the impact that different compound properties had on cell survival.

Impact of matrix properties on the survival of freeze-dried bacteria.

Disaccharides sont, en g&eacute;n&eacute;ral, le premier choix comme formulation compos&eacute;s lorsque la lyophilisation des micro-organismes. Polysaccharides et autres biopolym&egrave;res sont consid&eacute;r&eacute;es comme trop gros pour stabiliser et interagir avec les composants de la cellule de la m&ecirc;me mani&egrave;re b&eacute;n&eacute;fique comme disaccharides, polym&egrave;res ont &eacute;t&eacute; signal&eacute;s &agrave; l&#39;appui de la survie cellulaire. Dans la pr&eacute;sente &eacute;tude, nous comparons l&#39;efficacit&eacute; du saccharose et les polym&egrave;res Ficoll, Hydroxy&eacute;thylcellulose, hydroxypropylm&eacute;thylcellulose et alcool polyvinylique pour soutenir la survie des trois souches bact&eacute;riennes lors de lyophilisation. Les conditions osmotiques initiales ont &eacute;t&eacute; ajust&eacute;es pour &ecirc;tre semblable pour toutes les pr&eacute;parations. Caract&eacute;risation de la formulation a &eacute;t&eacute; utilis&eacute;e pour interpr&eacute;ter l&#39;impact que diff&eacute;rentes propri&eacute;t&eacute;s compos&eacute;es sur la survie des cellules.

Incidence des propri&eacute;t&eacute;s de la matrice sur la survie des bact&eacute;ries lyophilis&eacute;es.

Disaccharide sind in der Regel die erste Wahl als Formulierung Verbindungen beim Gefriertrocknen von Mikroorganismen. Obgleich Polysaccharide und andere Biopolymere zu gro&szlig; betrachtet sind, zu stabilisieren und die Interaktion mit dem Zellbestandteile vorteilhaft wie Disaccharide, wurde Polymere berichtet, Zelle &uuml;berleben zu unterst&uuml;tzen. In der vorliegenden Studie vergleichen wir die Effizienz der Saccharose und die Polymere Ficoll, Hydroxyethylcellulose, Hydroxypropylmethylcellulose und Polyvinylalcohol zu unterst&uuml;tzen, das &Uuml;berleben der drei Bakterienst&auml;mme w&auml;hrend der Trocknung Einfrieren. Osmotischen Anfangsbedingungen wurden angepasst, um f&uuml;r alle Formulierungen &auml;hnlich sein. Formulierung Charakterisierung wurde verwendet, um die Auswirkungen zu interpretieren, dass verschiedene zusammengesetzte Eigenschaften auf das &Uuml;berleben der Zelle hatte.

Auswirkungen der Matrix-Eigenschaften auf das &Uuml;berleben der gefriergetrockneten Bakterien.

Disaccaridi sono, in generale, la prima scelta come formulazione composti quando liofilizzazione microrganismi. Sebbene polisaccaridi e altri biopolimeri sono considerati troppo grandi per stabilizzare e interagire con i componenti delle cellule allo stesso modo benefico come disaccaridi, polimeri sono stati segnalati per sostenere la sopravvivenza delle cellule. Nel presente studio abbiamo confrontare l&#39;efficienza di saccarosio e polimeri di Ficoll, hydroxyethylcellulose, idrossipropilmetil e polyvinylalcohol per sostenere la sopravvivenza di tre ceppi batterici durante liofilizzazione. Le condizioni iniziali osmotiche sono state adeguate per essere simile per tutte le formulazioni. Caratterizzazione di formulazione venne utilizzato per interpretare l&#39;impatto che diverse propriet&agrave; composto aveva sulla sopravvivenza delle cellule.

Impatto delle propriet&agrave; matrix sulla sopravvivenza dei batteri liofilizzati.

&#x4E8C;&#x7CD6;&#x985E;&#x306F;&#x3001;&#x4E00;&#x822C;&#x7684;&#x306B;&#x306F;&#x3001;&#x6700;&#x521D;&#x306E;&#x9078;&#x629E;&#x80A2;&#x3068;&#x3057;&#x3066;&#x5B9A;&#x5F0F;&#x5316;&#x5316;&#x5408;&#x7269;&#x306E;&#x5FAE;&#x751F;&#x7269;&#x3092;&#x51CD;&#x7D50;&#x4E7E;&#x71E5;&#x3059;&#x308B;&#x3068;&#x304D;&#x3002;&#x591A;&#x7CD6;&#x985E;&#x3068;&#x4ED6;&#x306E;&#x751F;&#x4F53;&#x9AD8;&#x5206;&#x5B50;&#x3092;&#x5B89;&#x5B9A;&#x3055;&#x305B;&#x308B;&#x3057;&#x3001;&#x4E8C;&#x7CD6;&#x985E;&#x3068;&#x3057;&#x3066;&#x540C;&#x3058;&#x306E;&#x6709;&#x76CA;&#x306A;&#x65B9;&#x6CD5;&#x3067;&#x7D30;&#x80DE;&#x30B3;&#x30F3;&#x30DD;&#x30FC;&#x30CD;&#x30F3;&#x30C8;&#x3068;&#x3084;&#x308A;&#x53D6;&#x308A;&#x3059;&#x308B;&#x306E;&#x306B;&#x306F;&#x5927;&#x304D;&#x3059;&#x304E;&#x308B;&#x3068;&#x898B;&#x306A;&#x3055;&#x308C;&#x307E;&#x3059;&#x304C;&#x3001;&#x30DD;&#x30EA;&#x30DE;&#x30FC;&#x306F;&#x3001;&#x7D30;&#x80DE;&#x306E;&#x751F;&#x5B58;&#x3092;&#x30B5;&#x30DD;&#x30FC;&#x30C8;&#x3059;&#x308B;&#x305F;&#x3081;&#x306B;&#x5831;&#x544A;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x672C;&#x7814;&#x7A76;&#x3067;&#x306F;&#x30B9;&#x30AF;&#x30ED;&#x30FC;&#x30B9;&#x3068; Ficoll&#x3001;hydroxyethylcellulose&#x3001;&#x30D2;&#x30C9;&#x30ED;&#x30AD;&#x30B7;&#x30D7;&#x30ED;&#x30D4;&#x30EB;&#x30E1;&#x30C1;&#x30EB; &#x30BB;&#x30EB;&#x30ED;&#x30FC;&#x30B9;&#x3001;&#x30DD;&#x30EA;&#x30D3;&#x30CB;&#x30EB; &#x30A2;&#x30EB;&#x30B3;&#x30FC;&#x30EB;&#x4E2D;&#x306E; 3 &#x3064;&#x306E;&#x7D30;&#x83CC;&#x306E;&#x7DCA;&#x5F35;&#x306E;&#x751F;&#x5B58;&#x3092;&#x30B5;&#x30DD;&#x30FC;&#x30C8;&#x3059;&#x308B;&#x51CD;&#x7D50;&#x4E7E;&#x71E5;&#x30DD;&#x30EA;&#x30DE;&#x30FC;&#x306E;&#x52B9;&#x7387;&#x3092;&#x6BD4;&#x8F03;&#x3057;&#x307E;&#x3059;&#x3002;&#x521D;&#x671F;&#x306E;&#x6D78;&#x900F;&#x5727;&#x306E;&#x6761;&#x4EF6;&#x306F;&#x3059;&#x3079;&#x3066;&#x88FD;&#x5264;&#x306E;&#x4F3C;&#x3066;&#x3044;&#x308B;&#x3088;&#x3046;&#x306B;&#x8ABF;&#x6574;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;&#x5B9A;&#x5F0F;&#x5316;&#x306E;&#x6027;&#x683C;&#x63CF;&#x5199;&#x306B;&#x8907;&#x5408;&#x7279;&#x6027;&#x306E;&#x7570;&#x306A;&#x308B;&#x7D30;&#x80DE;&#x306E;&#x751F;&#x5B58;&#x306B;&#x4E0E;&#x3048;&#x305F;&#x5F71;&#x97FF;&#x3092;&#x89E3;&#x91C8;&#x3059;&#x308B;&#x4F7F;&#x7528;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;

&#x30DE;&#x30C8;&#x30EA;&#x30C3;&#x30AF;&#x30B9; &#x30D7;&#x30ED;&#x30D1;&#x30C6;&#x30A3;&#x51CD;&#x7D50;&#x4E7E;&#x71E5;&#x30D0;&#x30AF;&#x30C6;&#x30EA;&#x30A2;&#x306E;&#x751F;&#x5B58;&#x306B;&#x53CA;&#x307C;&#x3059;&#x5F71;&#x97FF;&#x3002;

Disaccharides&#xB294;, &#xC77C;&#xBC18;&#xC801;&#xC73C;&#xB85C; &#xBC30;&#xD569;&#xC73C;&#xB85C; &#xCCAB; &#xC120;&#xD0DD; &#xB54C; &#xBBF8;&#xC0DD;&#xBB3C; freeze-drying &#xD654;&#xD569;&#xBB3C;. &#xB2E4; &#xB2F9; &#xB958; &#xBC0F; &#xAE30;&#xD0C0; biopolymers &#xC548;&#xC815; disaccharides&#xB85C; &#xAC19;&#xC740; &#xC720;&#xC775;&#xD55C; &#xBC29;&#xC2DD;&#xC5D0;&#xC11C; &#xC140; &#xAD6C;&#xC131; &#xC694;&#xC18C; &#xC0C1;&#xD638; &#xC791;&#xC6A9;&#xC744; &#xB108;&#xBB34; &#xCEE4;&#xC11C; &#xAC04;&#xC8FC; &#xB429;&#xB2C8;&#xB2E4;, &#xC788;&#xC9C0;&#xB9CC; &#xACE0;&#xBD84;&#xC790; &#xC140; &#xC0DD;&#xC874;&#xC744; &#xC9C0;&#xC6D0; &#xD558;&#xAE30; &#xC704;&#xD574; &#xBCF4;&#xACE0; &#xB418;&#xC5C8;&#xC2B5;&#xB2C8;&#xB2E4;. &#xD604;&#xC7AC;&#xC758; &#xC5F0;&#xAD6C;&#xC5D0; &#xC6B0;&#xB9AC; &#xC790;&#xB2F9; &#xBC0F; &#xACE0;&#xBD84;&#xC790; Ficoll, hydroxyethylcellulose, hydroxypropylmethylcellulose &#xBC0F; polyvinylalcohol &#xC911; 3 &#xAC1C;&#xC758; &#xC138;&#xADE0;&#xC131; &#xAE34;&#xC7A5;&#xC758; &#xC0DD;&#xC874;&#xC744; &#xC9C0;&#xC6D0; &#xD558;&#xAE30; &#xC704;&#xD574; &#xB3D9;&#xACB0; &#xAC74;&#xC870;&#xC758; &#xD6A8;&#xC728;&#xC131;&#xC744; &#xBE44;&#xAD50;. &#xCD08;&#xAE30; &#xC0BC; &#xD22C; &#xC870;&#xAC74;&#xC774; &#xBE44;&#xC2B7;&#xD55C; &#xBAA8;&#xB4E0; &#xC81C;&#xD615;&#xC5D0; &#xB300; &#xD55C; &#xC870;&#xC815; &#xD588;&#xB2E4;. &#xBC30;&#xD569; &#xD2B9;&#xC131;&#xC740; &#xB2E4;&#xB978; &#xBCF5;&#xD569; &#xC18D;&#xC131; &#xC138;&#xD3EC; &#xC0DD;&#xC874;&#xC5D0; &#xC788; &#xC5C8; &#xBBF8;&#xCE58;&#xB294; &#xC601;&#xD5A5;&#xC744; &#xD574;&#xC11D; &#xD558;&#xB294; &#xC0AC;&#xC6A9; &#xB418;&#xC5C8;&#xB2E4;.

&#xD589;&#xB82C; &#xC18D;&#xC131; &#xB3D9;&#xACB0;&#xB41C; &#xBC15;&#xD14C;&#xB9AC;&#xC544;&#xC758; &#xC0DD;&#xC874;&#xC5D0; &#xBBF8;&#xCE58;&#xB294; &#xC601;&#xD5A5;.

Disac&aacute;ridos son, en general, la primera opci&oacute;n como formulaci&oacute;n compuestos cuando los microorganismos de la liofilizaci&oacute;n. Aunque se consideran demasiado grandes para estabilizar e interactuar con los componentes de la c&eacute;lula de la misma manera beneficiosa como disac&aacute;ridos polisac&aacute;ridos y otros biopol&iacute;meros, pol&iacute;meros se han divulgado para apoyar la supervivencia celular. En el presente estudio se compara la eficacia de la sacarosa y los pol&iacute;meros Ficoll, HIDROXIETILCELULOSA, hidroxipropilmetilcelulosa y alcohol polivin&iacute;lico para apoyar la supervivencia de tres cepas bacterianas durante la liofilizaci&oacute;n. Las condiciones iniciales osm&oacute;ticas se ajustaron para ser similares para todas las formulaciones. Caracterizaci&oacute;n de formulaci&oacute;n sol&iacute;a interpretar el impacto que distintas propiedades compuestos tuvieran en la supervivencia celular.

Impacto de las propiedades de la matriz sobre la supervivencia de bacterias liofilizadas.

Gold nanoparticles (AuNPs) coated with stabilizing molecular monolayers are utilized in areas ranging from life sciences to nanoelectronics. Here we present a novel and facile one-pot single phase procedure for the preparation of stable AuNPs with good dispersity, which are coated with Î±,Ï‰-alkanedithiols whose outer Ï‰-thiol is protected by a triphenylmethyl group. Using dielectrophoresis we were able to trap these AuNPs, coated with Ï‰-thiol protecting groups, in a 20 nm gold electrode nanogap. The Ï‰-thiol group was then deprotected under acidic conditions in situ once the AuNPs were correctly positioned in the device. The subsequent deprotection resulted in an increase of conductance by up to 3 orders of magnitude, indicating that the isolated dithiol-coated AuNPs were fused into a covalently bonded network with AuNP-molecule-AuNP as well as electrode-molecule-AuNP linkages. Furthermore, complete characterization of the AuNP surface-bonded alkanedithiols was achieved using a series of one- and two-dimensional NMR spectroscopy techniques. Our spectra of the molecule-coated AuNPs show well-resolved signals, only slightly broader than for free molecules in solution, which is in contrast to many earlier reported NMR spectral data of molecules attached to AuNPs. Complementary diffusion NMR spectroscopic experiments were performed to prove that the observed alkanedithiols are definitely surface-bonded species and do not exist in free and unattached form.

Formation and NMR spectroscopy of Ï‰-thiol protected Î±,Ï‰-alkanedithiol-coated gold nanoparticles and their usage in molecular charge transport junctions.

Magnetic multilayered, onion-like, heterostructured nanoparticles are interesting model systems for studying magnetic exchange coupling phenomena. In this work, we synthesized heterostructured magnetic nanoparticles composed of two, three, or four components using iron oxide seeds for the subsequent deposition of manganese oxide. The MnO layer was allowed either to passivate fully in air to form an outer layer of Mn(3)O(4) or to oxidize partially to form MnO|Mn(3)O(4) double layers. Through control of the degree of passivation of the seeds, particles with up to four different magnetic layers can be obtained (i.e., FeO|Fe(3)O(4)|MnO|Mn(3)O(4)). Magnetic characterization of the samples confirmed the presence of the different magnetic layers.

Two-, three-, and four-component magnetic multilayer onion nanoparticles based on iron oxides and manganese oxides.

The use of single molecules as building blocks for practical electronic devices and sensors has high potential for novel applications due to the versatility of electronic properties of the molecules. Nano-sized molecules offer great potential for further miniaturization of electronic devices. We describe a method where such molecules are used to bridge a nanoparticles-nanoelectrode interface and thus determine the electrical properties of such a junction. We describe in detail the fabrication of the platform, its functionalization with molecules, and the basics of the electrical measurements. This platform has been shown to guide electrical current through a few molecules. The versatility of such nanoparticle-molecule-nanoelectrode heterojunctions makes this platform suitable for both basic molecular electronics measurements and also for molecular sensing devices in biological and medical applications.

Nanoparticle bridges for studying electrical properties of organic molecules.

The focused-ion-beam (FIB) is the method of choice for site-specific sample preparation for Transmission Electron Microscopy (TEM) in material sciences. A lamella can be physically lifted out from a specific region of a bulk specimen with submicrometer precision and thinned to electron transparency for high-resolution imaging in the TEM. The possibility to use this tool in life sciences applications has been limited by the lack of lift-out capabilities at the cryogenic temperatures often needed for biological samples. Conventional cryo-TEM sample preparation is mostly based on ultramicrotomy, a procedure that is not site-specific and known to produce artifacts. Here we demonstrate how a cooled nanomanipulator and a custom-built transfer station can be used to achieve cryo-preparation of TEM samples with the FIB, enabling high-resolution investigation of frozen-hydrated specimens in the TEM.

Klaus Leifer

Department of Engineering Sciences

Uppsala University

Formulations for Freeze-drying of Bacteria and Their Influence on Cell Survival

Cryo-electron Microscopy Specimen Preparation By Means Of a Focused Ion Beam

Klaus Leifer

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

Uppsala University

Formulations for Freeze-drying of Bacteria and Their Influence on Cell Survival

Cryo-electron Microscopy Specimen Preparation By Means Of a Focused Ion Beam

Department of Engineering Sciences