Name: particles without a box: brush-first synthesis of photodegradable peg star polymers under ambient conditions
Uploaded: 2013-10-10T21:30:00
Description: Watch this Scientific Journal Video about Particles without a Box: Brush-first Synthesis of Photodegradable PEG Star Polymers under Ambient Conditions at JoVE.com

Vi takker MIT Institut for Kemi og MIT Lincoln Labs avancerede koncepter Udvalget for støtte til dette arbejde.

Vi først beskriver syntesen og oprensningen af PEG-MM B fra 3 kDa O-(2-aminoethyl) polyethylenglycol (PEG-NH2) og norbornen-N-hydroxysuccinimidyl (NHS)-ester. Den førstnævnte forbindelse kan købes fra Sigma Aldrich Inc. eller fremstillet via anioniske polymerisation ifølge litteraturprocedurer 22,23. Den sidstnævnte forbindelse kan fremstilles i to trin i henhold til en offentliggjort procedure 21. Næste vi beskriver en syntese af katalysator <em...

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Chem. 74, 6080-6087 (2002).</li><li>Otani, H., Fujita, S., Watanabe, Y., Fujiki, M., Nomura, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Facile,+Controlled+Synthesis+of+Soluble+Star+Polymers+Containing+a+Sugar+Residue+by+Ring-Opening+Metathesis+Polymerization+(ROMP).">A Facile, Controlled Synthesis of Soluble Star Polymers Containing a Sugar Residue by Ring-Opening Metathesis Polymerization (ROMP).</a> Macromol. Symp. 293, 53-57 (2010).</li><li>Nomura, K., Watanabe, Y., Fujita, S., Fujiki, M., Otani, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Facile+Controlled+Synthesis+of+Soluble+Star+Shape+Polymers+by+Ring-Opening+Metathesis+Polymerization+(ROMP).">Facile Controlled Synthesis of Soluble Star Shape Polymers by Ring-Opening Metathesis Polymerization (ROMP).</a> Macromolecules. 42, 899-901 (2009).</li><li>Gao, H., Ohno, S., Matyjaszewski, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low+Polydispersity+Star+Polymers+via+Cross-Linking+Macromonomers+by+ATRP.">Low Polydispersity Star Polymers via Cross-Linking Macromonomers by ATRP.</a> J. Am. Chem. Soc. 128, 15111-15113 (2006).</li><li>Liu, J., Burts, A. O., Li, Y., Zhukhovitskiy, A. V., Ottaviani, M. F., Turro, N. J., Johnson, J. 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Den vigtigste fordel ved brush-første BASP syntese er den unikke evne til hurtigt at syntetisere nanostrukturer med forskellig størrelse og sammensætning parallelt uden behov for specialiseret udstyr. I denne undersøgelse viser vi pensel første syntetiske fremgangsmåde under anvendelse af en norbomen funktionaliseret PEG makromonomer (B, figur 1) og en bis-norbornen nitrobenzylester tværbinder (C, figur 1). PEG-kæderne fra B bibringer ...

Polymere nanopartikler er blevet nøje undersøgt for deres potentielle anvendelse som platforme for drug delivery, understøttet katalyse, biologisk billedbehandling og saml-selv 1-3. Moderne programmer kræver, at nanopartikler synteser være facile, reproducerbare, er forenelig med kemiske funktionaliteter, og gøres til genstand for diversificering 4,5. Ringåbnende metathesis polymerisation (ROMP) anstrengt olefiner er en kraftfuld metode til syntese af funktionelle polymere nanostrukturer med kontrollerede størrelser og smalle massedistributioner 1,6-8. For eksempel kan norbornen-funktionaliserede poly (ethylenglycol) (PEG) makromonomerer (MMS) effektivt polymeriseret via ROMP at generere vandopløselige flaske-børste polymerer. Med denne fremgangsmåde kan nanostrukturer, der bærer flere løsbare medikamentmolekyler, fluoroforer og spin-kontrastmidler forberedes hurtigt og parallelt 6, 9, 10. ROMP er også blevet anvendt til &quot;arm først&quot; syntese af stjerne polymerer. I armen-første metode, lineære polymerer tværbundet med en multi-funktionel tværbinder at give sfæriske nanostrukturer med polymere arme. Schrock og medarbejdere rapporterede den første arm-first ROMP syntese af stjerne polymerer via krydsbinding af norbornen, dicarbomethoxynorbornadiene og trimethylsilylhalogenider beskyttet dicarboxynorbornene lineære polymerer med et bifunktionelt norbomen tværbinder. 11, har 12 Buchmeiser udvidet denne metode til syntese af materialer med en vifte af applikationer, der omfatter understøttet katalyse, vævs-engineering, og kromatografi 13-17. Otani og medarbejdere har gjort stjerne polymer nanopartikler med funktionelle overflader via en beslægtet &quot;ind-ud&quot; polymerisering strategi 18, 19. De fleste arm-først polymerisationer indebærer et komplekst samspil af monomere, polymer, og stjerne koblingsreaktioner. The sidstnævnte forløber via en trin-vækst mekanisme, der typisk fører til bred molekylvægt (MW) distributioner. For at overvinde denne begrænsning i relaterede arm-første atom transfer radikal polymerisationsreaktioner, Matyjaszewski og kolleger udførte arm-første krydsbinding af præfabrikerede polymere MMS til at give stjerne polymerer med meget smalle MW distributioner 20. I dette tilfælde, den steriske hovedparten af ​​MMS, og den øgede andel af stjerne våben til indvielse sites, hæmmet dårligt kontrolleret stjerne + stjerne koblingsprocesser, og førte til en levende, kæde vækst mekanisme. Da vi forsøgte den samme strategi i forbindelse med ROMP med en norbomen-termineret PEG-MM og en bis-norbomen crosslinker blev stjerne polymerer med meget brede, multimodale MW distributioner opnået. Dette resultat antydede, at MM alene i dette system ikke var tilstrækkeligt omfangsrigt til at hæmme stjerne + stjerne kobling. For at øge den steriske hovedparten af ​​de stjerne arme og potentielt begrænse denne uncontrolled kobling, vi forsøgte at først polymerisere MM til at danne flaske børste polymerer i fravær af tværbinder og derefter tilføje krydsbinderen. Vi var glad for at finde, at der under visse betingelser, denne &quot;brush-først&quot;-metoden, forudsat ligetil adgang til &quot;brush-arm stjerne polymerer&quot; (BASPs) med smalle MW fordelinger og tunable kerne og Corona funktionaliteter. Vi har for nylig rapporteret brush-første ROMP syntese af PEG BASPs hjælp Grubbs 3. generation katalysator A (figur 1) 21. I dette arbejde, eksponering af PEG-MM B til katalysator A genererede et levende pensel makroinitiator med defineret rygrad længde (B1, figur 1). Overførsel af portioner af B 1 til hætteglas, der indeholdt forskellige mængder af tværbinder C indledt BASPformation. MW, og dermed størrelsen af de BASPs steg geometrisk med mængden af C tilsat. Vi gav en mekanistisk hypotese for denne geometriske vækst proces og viste, at funktionelle, nitroxid core-og Corona-mærket BASPs let kan fremstilles uden behov for post-polymerisationsprodukter modifikation trin eller sekventiel monomer tilføjelser. Men i alle de rapporterede eksempler, var vi bekymrede katalysatordeaktivering, vi udført alle reaktioner under N2 atmosfære inde i en handskerummet. Siden vores første rapport, har vi fundet, at børsten-første metode er meget effektiv for dannelsen af ​​BASPs fra en bred vifte af norbornentype opsagt MMS og funktionelle tværbindingsmidler. Vi har også opdaget, at metoden kan udføres i laboratoriet med ingen særlige forholdsregler for at fjerne luft eller fugt. Heri vil en serie af tre BASPs af forskellig MWs skal SYnthesized af brush-første metode under omgivende forhold. Kort sagt, vil 10 ækvivalenter af B udsættes til 1,0 ækvivalenter katalysator A (figur 1a) i 15 minutter til opnåelse af en BI med en gennemsnitlig polymerisationsgrad (DP) på 10. Tre portioner af dette parti BI vil blive overført til separate hætteglas, der indeholder 10, 15 og 20 ækvivalenter (N, figur 1b) C. Efter 4 timer, vil polymerisationerne blive undertrykt via tilsætning af ethylvinylether. De stjerne polymer MWs og MW distributioner vil blive præget ved hjælp af en gelpermeeringschromatografi instrument udstyret med en multi-vinkel laserlysspredning detektor (GPC-malls).

<table border="0" cellpadding="0" cellspacing="0" width="592">
	<colgroup>
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	</colgroup>
	<tbody>
		<tr height="42">
			<td height="84" rowspan="2" style="height:84px;width:216px;">Grubbs Second Generation Catalyst</td>
			<td rowspan="2" style="width:91px;">Materia (or Sigma Aldrich)</td>
			<td rowspan="2" style="width:119px;">C848 (Sigma Aldrich: 569747)</td>
			<td style="width:167px;">
			Used as purchased from manufacturer. 
 *Provided as a generous gift.
			</td>
		</tr>
		<tr height="42">
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Pyridine</td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td style="width:119px;">270970</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">O-(2-aminoethyl)polyethylene glycol 3000</td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td style="width:119px;">07969</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">PEG-MM</td>
			<td style="width:91px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">Synthesized following reported procedures (Ref. 21, protocol 1)</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">norbornene-N-hydroxysuccinimidyl (NHS) ester</td>
			<td style="width:91px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">Synthesized following reported procedures (Ref. 21)</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Bis-norb-NBOC Crosslinker</td>
			<td style="width:91px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">Synthesized following reported procedures (Ref. 21)</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Pentane</td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td style="width:119px;">158941</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Tetrahydrofuran (HPLC grade)</td>
			<td style="width:91px;">Sigma Aldrich </td>
			<td style="width:119px;">34865</td>
			<td style="width:167px;">Dried and purified over a solvent purification columns </td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Dichloromethane</td>
			<td style="width:91px;">VWR </td>
			<td>BDH1113-4LG</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Acetonitrile (HPLC grade)</td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td style="width:119px;">34998</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Acetic Acid </td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td style="width:119px;">A6283</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Sodium sulfate </td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td>239313</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Diethyl ether</td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td style="width:119px;">673811</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Dimethylformamide (HPLC grade) </td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td style="width:119px;">270547</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Lithium Bromide</td>
			<td style="width:91px;">Sigma Aldrich</td>
			<td style="width:119px;">213225</td>
			<td style="width:167px;">Used as purchased from manufacturer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">MillQ Biocel A10</td>
			<td style="width:91px;">Millipore</td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Beckmann Coulter HPLC (127p solvent module, 166p detector)</td>
			<td style="width:91px;">Beckmann Coulter</td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Zorbax 300SB-C18 PrepHT reverse phase column </td>
			<td style="width:91px;">Agilent</td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">1260 Infinity Liquid Chromatography </td>
			<td style="width:91px;">Agilent</td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">GPC KD-806M column</td>
			<td style="width:91px;">Shodex</td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Dawn Heleos II Light Scatterer</td>
			<td style="width:91px;">Wyatt</td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Optilab T-rEX Refractive Index Detector</td>
			<td style="width:91px;">Wyatt</td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Glass Scintillation Vials - 40 ml</td>
			<td style="width:91px;">Chemglass</td>
			<td>CG-4909-05</td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Glass Scintillation Vials - 4 ml </td>
			<td style="width:91px;">Chemglass</td>
			<td style="width:119px;">CG-4904-06</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Glass Scintillation Vials (PTFE-lined cap) - 2 ml </td>
			<td style="width:91px;">Agilent</td>
			<td>5183-4518</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Stir-bars</td>
			<td style="width:91px;">VWR</td>
			<td style="width:119px;">5894x</td>
			<td style="width:167px;">various sizes </td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">13 mm 0.45 &#181;m Nylon Syringe filter</td>
			<td style="width:91px;">PerkinElmer</td>
			<td>02542903</td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">13 mm 0.45 &#181;m polytetrafluoroethylene syringe filter</td>
			<td style="width:91px;">PerkinElmer</td>
			<td>02542909</td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">1 ml disposable syringes </td>
			<td style="width:91px;">VWR</td>
			<td style="width:119px;">53548-001</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Swing bucket centrifuge or similar</td>
			<td style="width:91px;"> </td>
			<td style="width:119px;"> </td>
			<td style="width:167px;">Should be able to reach approximately 4,000 rpm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Round bottom flask</td>
			<td style="width:91px;"> </td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Fritted glass filter assembly </td>
			<td style="width:91px;"> </td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Rotary Evaporator </td>
			<td style="width:91px;"> </td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Balance </td>
			<td style="width:91px;"> </td>
			<td style="width:119px;"> </td>
			<td style="width:167px;"> </td>
		</tr>
	</tbody>
</table>

particles without a box: brush-first synthesis of photodegradable peg star polymers under ambient conditions

Praktiske metoder til hurtig, parallel syntese af forskelligt funktionaliserede nanopartikler vil muliggøre opdagelsen af ​​nye formuleringer til drug delivery, biologisk billeddannelse, og støttede katalyse. I denne rapport, viser vi, parallel syntese af børste-arm stjerne polymer (BASP) nanopartikler af &quot;brush-first&quot;-metoden. I denne metode, er en norbomen-termineret poly (ethylenglycol) (PEG) makromonomer (PEG-MM) først polymeriseret via ring-åbning metatese polymerisation (ROMP) til at generere en levende pensel makroinitiator. Portioner af denne initiator stamopløsning tilsættes til hætteglas, der indeholder forskellige mængder af et lysnedbrydelig bis-norbornen tværbinder. Udsættelse for Tværbinderen indleder en serie af kinetisk styret børste + børste og stjerne +-stjernede koblingsreaktioner der i sidste ende giver BASPs med kerner består af tværbindingsmidlet og coronas bestående af PEG. Den endelige BASP størrelse afhænger af mængden af ​​tværbinder tilføjet. Vi udføre synafhandling af tre BASPs på bordplade med ingen særlige forholdsregler for at fjerne luft og fugt. Prøverne er karakteriseret ved gelpermeationskromatografi (GPC), resultater aftalt tæt sammen med vores tidligere rapport, der udnyttede inerte (handskerummet) betingelser. Væsentlige praktiske egenskaber, fordele og potentielle ulemper ved pensel første metode diskuteres.

Figur 2 viser GPC spor for en række BASPs fremstillet fra B1, B2 og B3. I alle tilfælde skal de data illustrerer, at stigende ækvivalenterne af tværbinder (N) fører til en stigning i størrelsen af BASP. Som det blev observeret i vores tidligere rapport, 10 ækvivalenter tværbinder ikke er tilstrækkelig til at opnå ensartede BASPs, N = 10 prøve viser et tydeligt multimodal GPC spor med en stor mængde af resterende pensel pol...

Watch this Scientific Journal Video about Particles without a Box: Brush-first Synthesis of Photodegradable PEG Star Polymers under Ambient Conditions at JoVE.com

Particles without a Box: Brush-first Synthesis of Photodegradable PEG Star Polymers under Ambient Conditions

Poly (ethylenglycol) (PEG) børste-arm stjerne polymerer (BASPs) med smalle massedistributioner og afstemmelige nanoskopiske størrelser er syntetiseret via ringåbnende metathesis polymerisation (ROMP) af et PEG-norbornen makromonomer efterfulgt af overførsel af portioner af den resulterende levende pensel initiativtager til hætteglas indeholdende forskellige mængder af et stift, foto spaltbar bis-norbornen-tværbinder.

Partikler uden boks: Brush-første syntese af lysnedbrydelig PEG stjerne Polymers under omgivelsesbetingelser

Convenient methods for the rapid, parallel synthesis of diversely functionalized nanoparticles will enable discovery of novel formulations for drug ...

Research

JoVE Journal

Chemistry

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions

Mizoroki-Heck krydskoblingsreaktioner katalyseret af dichlor {bis [1,1 &#39;, 1&#39;&#39; - (phosphinetriyl) tripiperidine]} palladium Under milde reaktionsbetingelser

Dichloro-bis(aminophosphine) complexes of palladium with the general formula of [(P{(NC5H10)3-n(C6H11)n})2Pd(Cl)2] (where n = 0-2), belong to a new family ...

A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions

En simpel metode til størrelse Kontrolleret Syntese af stabile Oligomere Klynger af guld nanopartikler under omgivende betingelser

Reducing dilute aqueous HAuCl4 with sodium thiocyanate (NaSCN) under alkaline conditions produces 2 to 3 nm diameter nanoparticles. Stable grape-like ...

Visualization of Ambient Mass Spectrometry with the Use of Schlieren Photography

Visualisering af Ambient massespektrometri med brug af Schlieren Photography

This manuscript outlines how to visualize mass spectrometry ambient ionization sources using schlieren photography. In order to properly optimize the mass ...

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Syntese af cycliske polymere og karakterisering af deres diffusive Motion i Melt stat på det indre Molecule Level

We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single ...

Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments

Facile fremstilling af ultrafine aluminiumhydroxidpartikler med eller uden mesoporøs MCM-41 i omgivende omgivelser

An aqueous suspension of nanogibbsite was synthesized via the titration of aluminum aqua acid [Al(H2O)6]3+ with L-arginine to pH 4.6. Since the hydrolysis ...

Facet-to-facet Linking of Shape-anisotropic Colloidal Cadmium Chalcogenide Nanostructures

Facet til facet sammenkædning af form-anisotrope kolloid Cadmium Chalcogenide nanostrukturer

Here, we describe a protocol that allows for shape-anisotropic cadmium chalcogenide nanocrystals (NCs), such as nanorods (NRs) and tetrapods (TPs), to be ...

Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy

Fase Behavior af ladede vesikler symmetriske og asymmetriske løsning betingelser overvåges med Fluorescens mikroskopi

Phase-separated giant unilamellar vesicles (GUVs) exhibiting coexisting liquid-ordered and liquid-disordered domains are a common biophysical tool to ...

Synthesis of Core-shell Lanthanide-doped Upconversion Nanocrystals for Cellular Applications

Syntese af kerne-shell Lanthanide-doped Upconversion nanokrystaller for cellulære applikationer

Lanthanide-doped upconversion nanocrystals (UCNs) have attracted much attention in recent years based on their promising and controllable optical ...

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

Elektrokemiske impedans spektroskopi som et redskab for elektrokemisk sats konstant estimering

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). ...

Solid-phase Synthesis of [4.4] Spirocyclic Oximes

Fast-fase syntese af [4.4] Spirocyclic Oximes

A convenient synthetic route for spirocyclic heterocycles is well sought after due to the molecule&#39;s potential use in biological systems. By means of ...