Name: a 'plug and play' method to create water-dispersible nanoassemblies containing an amphiphilic polymer, organic dyes and upconverting nanoparticles
Uploaded: 2015-11-14T13:00:00
Description: Watch this Scientific Journal Video about A 'Plug and Play' Method to Create Water-dispersible Nanoassemblies Containing an Amphiphilic Polymer, Organic Dyes and Upconverting Nanoparticles at JoVE.com

This research was supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada, the Canada Research Chairs Program, and Simon Fraser University. This work made use of 4D LABS shared facilities supported by the Canada Foundation for Innovation (CFI), British Columbia Knowledge Development Fund (BCKDF) and Simon Fraser University.

1. Síntese do 4 NaYF / Yb 3+ / Er 3+ Upconverting Nanopartículas (UCNP) <ol><li> Configure o aparelho como se segue: <ol><li> Coloque um manto de aquecimento 250 ml em uma placa de agitação regular e ligue o manto para o casal térmica. </li><li> Coloque um bal de fundo redondo de 250 ml equipado com uma barra de agitação magnética para a manta de aquecimento com aperto apropriado. </li><li> Conecte um adaptador de ar para o pescoço esquerdo do balão de fundo redondo e conecta...

<ol>
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As nanopartículas sintetizado de acordo com este protocolo tem uma distribuição de tamanho de 20 a 25 nm centrada em torno de 22,5 26,27 nm. Eles podem ser classificados como partículas esféricas com uma estrutura de rede 4 de acolhimento α-NaYF. Existem dois passos críticos neste protocolo. Na síntese UCNP, é crucial para manter a temperatura de aquecimento e tempo tão preciso quanto possível para assegurar uma distribuição estreita de tamanho de partícula. A adição simultânea de ...

Hoje ainda há uma necessidade urgente de desenvolver novos tipos de agentes de bio-imagem. Muitas novas sondas fluorescentes têm sido bem documentadas. 1-6 No entanto, melhorias substanciais na resolução de imagem continua a ser um desafio. 7 Um método prático é para modular directamente as sondas de fluorescência entre um estado emissivo &#39;light&#39; e um estado extinta &#39;dark&#39;. 12/08 Este método particular tem sido aplicado no desenvolvimento de tecnologias como o empobrecimento da emissão estimulada (STED) microscopia 13 e microscopia óptica reconstrução estocástico (STORM). 14 Outra abordagem para modular a fluorescência é acoplar cromóforos fotossensíveis juntamente com sondas fluorescentes. 15,16 Alternando o cromóforo fotossensíveis entre dois isómeros em que apenas um dos isómeros pode actuar como um aceitador de transferência de energia eficiente, permite o controle sobre extinção da fluorescência do po dee sonda através de transferência Förster Ressonância Energia (FRET) e outros mecanismos. O resultado é a criação de um estado emissiva e extinguiu-se um estado que pode ser alternado por exposição do cromóforo fotossensíveis para diferentes comprimentos de onda de luz. Cromóforos diarylethene fotossensíveis pode ser reversivelmente alternada entre um isómero de anel aberto incolor e um isómero de anel fechado de cor após irradiação com UV e luz visível 17-19 A estabilidade térmica dos dois isómeros e os espectros de absorção sintonizável do anel fechado composição isómero. diarylethenes muito bons candidatos como FRET controlável aceitantes. nanopartículas 20-23 Lanthanide dopado NaYF 4 upconverting são úteis para bio-imagem. 24 Estas nanopartículas absorvem a luz infravermelha próxima e emitem luz em várias regiões do espectro visível. Exemplos de modulação de fluorescência através da combinação de cromóforos diarylethene fotossensíveis e nanopartículas foram previamenteriormente relatado pelo nosso grupo. 25-27 No entanto, os sistemas descritos em cada exemplo necessária uma modificação sintética adicional para unir as diarylethenes à superfície das nanopartículas, o que complica o desenvolvimento de sistemas mais diversos. Aqui demonstramos um método simples &quot;plug-and-play &#39;para preparar moléculas de corante orgânico dispersíveis em água e nanopartículas fotossensíveis upconverting usando uma estratégia de auto-montagem. A escolha dos polímeros; poli (anidrido maleico estireno-alt) e poliéter amina 2,070 fornecer um ambiente hidrofílico e hidrofóbico. As secções hidrófobas do polímero ajuda a manter as moléculas orgânicas insolúveis em água e normalmente nanopartículas upconverting juntos, enquanto que a região hidrófila do polímero é essencial para manter a solubilidade em água. Vamos primeiro demonstrar síntese das nanopartículas upconverting pelo método de nucleação térmica. Então, vamos provar how as moléculas orgânicas e nanopartículas upconverting são encapsulados dentro de regiões hidrofóbicas do invólucro de polímero e permanecem estáveis ​​em meio aquoso por simplesmente co-agitação de uma solução do nanopartículas upconverting, polímero e diferentes moléculas de corantes orgânicos, seguido por um procedimento de trabalho conveniente. Nós também demonstrar como para modular a emissão de fluorescência das montagens usando a irradiação de luz externa. Nós antecipamos o âmbito da utilização deste método &#39;plug-and-play &quot;para fazer nanoassemblies dispersíveis em água continuará a se expandir.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>yttrium acetate</td>
			<td>sigma</td>
			<td>326046</td>
			<td>Yttrium(III) acetate hydrate</td>
		</tr>
		<tr>
			<td>ytterbium acetate</td>
			<td>sigma</td>
			<td>544973</td>
			<td>&#160;Ytterbium(III) acetate hydrate&#160;</td>
		</tr>
		<tr>
			<td>erbium acetate</td>
			<td>sigma</td>
			<td>325570</td>
			<td>Erbium(III) acetate hydrate</td>
		</tr>
		<tr>
			<td>oleic acid</td>
			<td>sigma</td>
			<td>75096</td>
			<td>analytical standard</td>
		</tr>
		<tr>
			<td>octadecene</td>
			<td>sigma</td>
			<td>O806&#160;</td>
			<td>Technical grade&#160;</td>
		</tr>
		<tr>
			<td>NaOH</td>
			<td></td>
			<td>S5881&#160;</td>
			<td>reagent grade</td>
		</tr>
		<tr>
			<td>NH4F</td>
			<td></td>
			<td>216011</td>
			<td>ACS reagent</td>
		</tr>
		<tr>
			<td>poly(styrene-alt-maleic anhydride)</td>
			<td>sigma</td>
			<td>4422699</td>
			<td>Average Mn= 1700</td>
		</tr>
		<tr>
			<td>JeffAmine 2070</td>
			<td>Huntsman</td>
			<td>M-2070</td>
			<td></td>
		</tr>
		<tr>
			<td>Varian Carry 300</td>
			<td>Agilent</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>JDSU NIR laser</td>
			<td>JSDU</td>
			<td>L4-9897510-100M</td>
			<td>980 nm diode laser</td>
		</tr>
	</tbody>
</table>

a 'plug and play' method to create water-dispersible nanoassemblies containing an amphiphilic polymer, organic dyes and upconverting nanoparticles

In this protocol, we first describe a procedure to synthesize lanthanide doped upconverting nanoparticles (UCNPs). We then demonstrate how to generate amphiphilic polymers in situ, and describe a protocol to encapsulate the prepared UCNPs and different organic dye molecules (porphyrins and diarylethenes) using polymer shells to form stable water-dispersible nanoassemblies. The nanoassembly samples containing both the UCNPs and the diarylethene organic dyes have interesting photochemical and photophysical properties. Upon 365 nm UV irradiation, the diarylethene group undergoes a visual color change. When the samples are irradiated with visible light of another specific wavelength, the color fades and the samples return to the initial colorless state. The samples also emit visible light from the UCNPs upon irradiation with 980 nm near-infrared light. The emission intensity of the samples can be tuned through alternate irradiation with UV and visible light. Modulation of fluorescence can be performed for many cycles without observable degradation of the samples. This versatile encapsulation procedure allows for the transfer of hydrophobic molecules and nanoparticles from an organic solvent to an aqueous medium. The polymer helps to maintain a lipid-like microenvironment for the organic molecules to aid in preservation of their photochemical behavior in water. Thus this method is ideal to prepare water-dispersible photoresponsive systems. The use of near-infrared light to activate upconverting nanoparticles allows for lower energy light to be used to activate photoreactions instead of more harmful ultraviolet light.

Espectros de absorção e espectros de fotoluminescência foram coletadas para amostra DAE-UCNP. Os espectros de absorção são usados ​​para comparar a sobreposição espectral entre os cromóforos diarylethene fechadas e as nanopartículas upconverting. As fotografias das amostras (tanto TPP-UCNP e DAE-UCNP) também foram incluídos para demonstrar a encapsulação bem sucedida das moléculas de corante e nanopartículas upconverting orgânicos, que estão localizados dentro das conchas polímero anfifílico na f...

Watch this Scientific Journal Video about A 'Plug and Play' Method to Create Water-dispersible Nanoassemblies Containing an Amphiphilic Polymer, Organic Dyes and Upconverting Nanoparticles at JoVE.com

A 'Plug and Play' Method to Create Water-dispersible Nanoassemblies Containing an Amphiphilic Polymer, Organic Dyes and Upconverting Nanoparticles

Organic dye molecules and oleic acid coated upconverting nanoparticles are not water-soluble. This protocol describes a &#8216;plug and play&#8217; method that enables the transfer of organic dye molecules and upconverting particles from their initial hydrophobic solvent to water.

Um método &#39;Plug and Play&#39; para criar Nanoassemblies dispersáveis ​​em água contendo um polímero anfifílicas, corantes orgânicos e Upconverting Nanopartículas

In this protocol, we first describe a procedure to synthesize lanthanide doped upconverting nanoparticles (UCNPs). We then demonstrate how to generate ...

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