using-neutron-spin-echo-resolved-grazing-incidence-scattering-to

Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials

The spin echo resolved grazing incidence scattering (SERGIS) technique has been used to probe the length-scales associated with irregularly shaped ...

University of Sheffield

Blends of conjugated polymers are frequently used as the active semiconducting layer in light-emitting diodes and photovoltaic devices. Here we report the use of scanning near-field optical microscopy, scanning force microscopy and nuclear-reaction analysis to study the structure of a thin film of a phase-separated blend of two conjugated polymers prepared by spin-casting. We show that in addition to the well-known micrometre-scale phase-separated morphology of the blend, one of the polymers preferentially wets the surface and forms a 10-nm-thick, partially crystallized wetting layer. Using near-field microscopy we identify unexpected changes in the fluorescence emission from the blend that occurs in a 300-nm-wide band located at the interface between the different phase-separated domains. Our measurements provide an insight into the complex structure of phase-separated conjugated-polymer thin films. Characterizing and controlling the properties of the interfaces in such films will be critical in the further development of efficient optoelectronic devices.

Correlating structure with fluorescence emission in phase-separated conjugated-polymer blends.

Amorphous materials: Glasses with liquid-like surfaces.

Tough and smart.

When a thin glassy film is strained uniaxially, a shear deformation zone (SDZ) can be observed. The ratio of the thickness of the SDZ to that of the undeformed film is related to the maximum extension ratio, lambda, which depends on the entanglement molecular weight, M(e). We have measured lambda as a function of film thickness in strained freestanding films of polystyrene as a probe of M(e) in confinement. It is found that thin films stretch further than thick films before failure, consistent with the interpretation that polymers in thin films are less entangled than bulk polymers, thus the effective value of M(e) in thin films is significantly larger than that of the bulk. Our results are well described by a conceptually simple model based on the probability of finding intermolecular entanglements near an interface.

Chain entanglement in thin freestanding polymer films.

Spin-coating is a very widely used technique for making uniform thin polymer films. For example, the active layers in most experimental semiconducting polymer-based devices, such as light-emitting diodes and photovoltaics, are made this way. The efficiency of such devices can be improved by using blends of polymers; these phase separate during the spin-coating process, creating the complex morphology that leads to performance improvements. We have used time-resolved small-angle light scattering and light reflectivity during the spin-coating process to study the development of structure directly. Our results provide evidence that a blend of two polymers first undergoes vertical stratification; the interface between the stratified layers then becomes unstable, leading to the final phase-separated thin film. This has given us the basis for establishing a full mechanistic understanding of the development of morphology in thin mixed polymer films, allowing a route to the rational design of processing conditions so as to achieve desirable morphologies by self-assembly.

An interfacial instability in a transient wetting layer leads to lateral phase separation in thin spin-cast polymer-blend films.

Transducts &#x30CA;&#x30CE;&#x30B9;&#x30B1;&#x30FC;&#x30EB;&#x5206;&#x5B50;&#x5F62;&#x72B6;&#x5DE8;&#x8996;&#x7684;&#x904B;&#x52D5;&#x306B;&#x5909;&#x5316;&#x3059;&#x308B;&#x3053;&#x3068;&#x3001;&#x30B9;&#x30B1;&#x30FC;&#x30E9;&#x30D6;&#x30EB;&#x306A;&#x5408;&#x6210;&#x7B4B;&#x3092;&#x69CB;&#x7BC9;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;Affinely pH &#x523A;&#x6FC0;&#x306B;&#x5FDC;&#x7B54;&#x3057;&#x3066;&#x5909;&#x5F62;&#x3001;&#x4F5C;&#x696D;&#x6750;&#x6599;&#x3001;&#x81EA;&#x5DF1;&#x7D44;&#x7E54;&#x5316;&#x30D6;&#x30ED;&#x30C3;&#x30AF; &#x30B3;&#x30DD;&#x30EA;&#x30DE;&#x30FC; &#x30CA;&#x30CE;&#x30B9;&#x30B3;&#x758E;&#x6C34;&#x6027;&#x30C9;&#x30E1;&#x30A4;&#x30F3;&#x306E;&#x5F31;&#x3044; polyacid &#x30DE;&#x30C8;&#x30EA;&#x30C3;&#x30AF;&#x30B9;&#x3067;&#x3059;&#x3002;&#x30C7;&#x30D0;&#x30A4;&#x30B9;&#x3092;&#x3069;&#x3053;&#x7B4B;&#x8089;&#x7247;&#x6301;&#x3061;&#x4F5C;&#x696D;&#x3092;&#x884C;&#x3044;&#x3001;&#x767A;&#x751F;&#x529B;&#x3092;&#x6E2C;&#x5B9A;&#x3057;&#x3066;&#x96C6;&#x3081;&#x307E;&#x3057;&#x305F;&#x3002;&#x3064;&#x306A;&#x304C;&#x308C;&#x305F;&#x3068;&#x304D;&#x3053;&#x308C; 20 mW kg(-1) &#x306E;&#x30D4;&#x30FC;&#x30AF;&#x96FB;&#x529B;&#x3092; 10 nm &#x306E;&#x5F62;&#x306E;&#x30B7;&#x30EA;&#x30A2;&#x30EB;&#x306E;&#x6DFB;&#x52A0;&#x306B;&#x3088;&#x308B;&#x751F;&#x6210;&#x7121;&#x6599;&#x5B9F;&#x884C;&#x3057;&#x3066;&#x5316;&#x5B66;&#x30E2;&#x30FC;&#x30BF;&#x30FC;&#x3092;&#x5909;&#x66F4;&#x63D0;&#x4F9B;&#x3057;&#x307E;&#x3059;&#x5316;&#x5B66;&#x767A;&#x632F;&#x5668;&#x4EE5;&#x4E0A; 5 &#x6841;&#x306B;&#x30B9;&#x30B1;&#x30FC;&#x30EA;&#x30F3;&#x30B0;&#x3057;&#x307E;&#x3059;&#x3002;&#x30A2;&#x30D5;&#x30A3;&#x30F3;&#x5909;&#x5F62;&#x3068;&#x5805;&#x7262;&#x306A;&#x50CD;&#x304F;&#x6750;&#x6599;&#x5EFA;&#x8A2D;&#x30B9;&#x30B1;&#x30FC;&#x30E9;&#x30D6;&#x30EB;&#x306A;&#x7B4B;&#x8089;&#x306E;&#x30C7;&#x30D0;&#x30A4;&#x30B9;&#x306E;&#x305F;&#x3081;&#x306E;&#x7D50;&#x679C;&#x306B;&#x4E0A;&#x6607;&#x3092;&#x4E0E;&#x3048;&#x308B;&#x30B2;&#x30EB;&#x306E;&#x30CA;&#x30CE;&#x69CB;&#x9020;&#x306E;&#x6027;&#x8CEA;&#x3067;&#x3059;&#x3002;

&#x5316;&#x5B66;&#x30A8;&#x30CD;&#x30EB;&#x30AE;&#x30FC;&#x99C6;&#x52D5;&#x578B;&#x5408;&#x6210;&#x7B4B;&#x8089;&#x306E;&#x767A;&#x96FB;&#x3092;&#x5F80;&#x5FA9;&#x3057;&#x307E;&#x3059;&#x3002;

&#x53EF;&#x6269;&#x5C55;&#x7684;&#x5408;&#x6210;&#x808C;&#x8089;&#x5EFA;&#x6210; transducts &#x7EB3;&#x7C73;&#x7EA7;&#x5206;&#x5B50;&#x5F62;&#x72B6;&#x53D8;&#x4E3A;&#x5B8F;&#x89C2;&#x7684;&#x8BAE;&#x6848;&#x3002;&#x5DE5;&#x4F5C;&#x6750;&#x6599;&#xFF0C;&#x5176;&#x4E2D;&#x53D8;&#x5F62; affinely &#x4E2D;&#x5BF9; ph &#x503C;&#x523A;&#x6FC0;&#x7684;&#x53CD;&#x5E94;&#xFF0C;&#x662F;&#x5305;&#x62EC;&#x7EB3;&#x7C73;&#x758F;&#x6C34;&#x6027;&#x57DF;&#x5F31;&#x805A;&#x4E73;&#x9178;&#x77E9;&#x9635;&#x4E2D;&#x7684;&#x81EA;&#x7EC4;&#x88C5;&#x7684;&#x5D4C;&#x6BB5;&#x5171;&#x805A;&#x7269;&#x3002;&#x8BBE;&#x5907;&#x5DF2;&#x88AB;&#x88C5;&#x914D;&#xFF0C;&#x808C;&#x8089;&#x4E0D;&#x5728;&#x60AC;&#x81C2;&#x4E0A;&#x5DE5;&#x4F5C;&#xFF0C;&#x5E76;&#x751F;&#x6210;&#x8BE5;&#x90E8;&#x961F;&#x4E3A;&#x8861;&#x91CF;&#x6807;&#x51C6;&#x3002;&#x5F53;&#x8026;&#x5408;&#x5230;&#x8FD9;&#x5C31;&#x63D0;&#x4F9B;&#x4E86;&#x514D;&#x8D39;&#x7684;&#x8FD0;&#x884C;&#x5316;&#x5B66;&#x7535;&#x673A;&#x4E32;&#x884C;&#x52A0; 10 nm &#x5F62;&#x72B6;&#x751F;&#x6210; 20 &#x5146;&#x74E6; kg(-1) &#x5CF0;&#x503C;&#x529F;&#x7387;&#x7684;&#x6539;&#x53D8;&#x4E86;&#x8FD9;&#x4E00;&#x5316;&#x5B66;&#x632F;&#x8361;&#x5668;&#x7F29;&#x653E;&#x8D85;&#x8FC7; 5 &#x4E2A;&#x6570;&#x91CF;&#x7EA7;&#x3002;&#x5B83;&#x662F;&#x7EB3;&#x7C73;&#x51DD;&#x80F6;&#xFF0C;&#x5F15;&#x8D77;&#x7684;&#x4EFF;&#x5C04;&#x53D8;&#x5F62;&#x548C;&#x53EF;&#x6269;&#x5C55;&#x7684;&#x808C;&#x8089;&#x8BBE;&#x5907;&#x65BD;&#x5DE5;&#x7684;&#x9C81;&#x68D2;&#x5DE5;&#x4F5C;&#x6750;&#x6599;&#x4E2D;&#x7ED3;&#x679C;&#x7684;&#x6027;&#x8D28;&#x3002;

&#x5F80;&#x590D;&#x5F0F;&#x53D1;&#x7535;&#x9A71;&#x52A8;&#x5316;&#x5B66;&#x5408;&#x6210;&#x808C;&#x8089;&#x4E2D;&#x3002;

A scalable synthetic muscle has been constructed that transducts nanoscale molecular shape changes into macroscopic motion. The working material, which deforms affinely in response to a pH stimulus, is a self-assembled block copolymer comprising nanoscopic hydrophobic domains in a weak polyacid matrix. A device has been assembled where the muscle does work on a cantilever and the force generated has been measured. When coupled to a chemical oscillator this provides a free running chemical motor that generates a peak power of 20 mW kg(-1) by the serial addition of 10 nm shape changes that scales over 5 orders of magnitude. It is the nanostructured nature of the gel that gives rise to the affine deformation and results in a robust working material for the construction of scalable muscle devices.

Reciprocating power generation in a chemically driven synthetic muscle.

Un muscle synth&eacute;tique &eacute;volutif a &eacute;t&eacute; construit que transducts nanom&eacute;triques forme mol&eacute;culaire se transforme en mouvement macroscopique. Le mat&eacute;riel de travail, ce qui d&eacute;forme affinely en r&eacute;ponse &agrave; un stimulus de pH, est un copolym&egrave;re &agrave; blocs auto-assembl&eacute;s comprenant nanoscopiques domaines hydrophobe dans une matrice polyacide faible. Un dispositif a &eacute;t&eacute; assembl&eacute; o&ugrave; le muscle fonctionne sur un cantilever et on a mesur&eacute; la force g&eacute;n&eacute;r&eacute;e. Lorsque coupl&eacute; &agrave; un oscillateur chimique, que ceci fournit un moteur de course chimique gratuit qui g&eacute;n&egrave;re une puissance cr&ecirc;te de 20 mW kg(-1) par l&#39;addition de s&eacute;rie de 10 forme nm change qui &eacute;volue sur 5 ordres de grandeur. C&#39;est la nature nanostructur&eacute;s du gel qui donne lieu &agrave; la d&eacute;formation affine et les r&eacute;sultats dans un mat&eacute;riau de travail robuste pour la construction d&#39;appareils musculaires &eacute;volutives.

Alternatives de production d&#39;&eacute;lectricit&eacute; dans un muscle synth&eacute;tique chimiquement entra&icirc;n&eacute;e.

Ein skalierbarer synthetischer Muskel ist konstruiert worden, dass Transducts Nanoscale Molekulare Form in makroskopische Bewegung &auml;ndert. Arbeitsmaterials, die in Reaktion auf einen Reiz pH-Wert affinely verformt sich, ist einem monomolekularen-Blockcopolymer aus nanoskopische hydrophobe Dom&auml;nen in einer schwachen Polyacid-Matrix. Ein Ger&auml;t hat zusammengestellt worden, wo der Muskel funktioniert auf ein Tr&auml;ger und die Kraft generiert hat gemessen worden. An Waagen ein chemischer Oszillator Dies bietet ein kostenloser laufen chemischer Motor, der eine Spitzenleistung von 20 mW kg(-1) durch serielle Zugabe von 10 nm-Form erzeugt, die sich &uuml;ber 5 Gr&ouml;&szlig;enordnungen. Es ist die nanostrukturierte Natur des Gels, die die affine Verformung und die Ergebnisse in eine robuste Werkstoff f&uuml;r den Bau von skalierbaren Muskel-Ger&auml;ten entstehen.

Hergehenden Stromerzeugung in einer chemisch angetriebene synthetische Muskeln.

&Egrave; stato costruito un muscolo sintetico scalabile che transducts su scala nanometrica molecolare forma cambia in moto macroscopico. Il materiale di lavoro, che si deforma affinely in risposta a uno stimolo di pH, &egrave; un copolimero a blocchi auto-assemblati comprendente nanoscopica domini idrofobici in una matrice Poliacido debole. Un dispositivo &egrave; stato montato dove il muscolo lavorare su un cantilever e la forza generata &egrave; stata misurata. Quando accoppiato ad un oscillatore chimico che fornisce un libero motore funzionante chimico che genera una potenza di picco di 20 mW kg(-1) con l&#39;aggiunta seriale di forma nm 10 cambia che scale oltre 5 ordini di grandezza. &Egrave; la natura nanostrutturati del gel che d&agrave; origine alla deformazione affine e risultati in un robusto materiale di lavoro per la costruzione di dispositivi muscolo scalabile.

Alternativi di generazione di energia in un muscolo sintetico chimicamente guidato.

&#xD655;&#xC7A5; &#xAC00;&#xB2A5;&#xD55C; &#xD569;&#xC131; &#xADFC;&#xC721; transducts &#xB098;&#xB178; &#xBD84;&#xC790; &#xBAA8;&#xC591; &#xAC70;&#xC2DC;&#xC801;&#xC778; &#xBAA8;&#xC158;&#xC73C;&#xB85C; &#xBCC0;&#xACBD; &#xAC74;&#xC124; &#xB418;&#xC5B4; &#xC788;&#xB2E4;. PH &#xC790;&#xADF9;&#xC5D0; &#xB300; &#xD55C; &#xC751;&#xB2F5;&#xC5D0;&#xC11C; affinely &#xBCC0;&#xD615;, &#xC791;&#xC5C5; &#xC18C;&#xC7AC; &#xC804;&#xCCB4; &#xC57D;&#xD55C; polyacid &#xB9E4;&#xD2B8;&#xB9AD;&#xC2A4;&#xC758; &#xC18C;&#xC218; &#xB3C4;&#xBA54;&#xC778;&#xC73C;&#xB85C; &#xAD6C;&#xC131; &#xB41C; &#xC870;&#xB9BD;&#xB41C; &#xBE14;&#xB85D; &#xCF54; &#xD3F4;&#xB9AC;&#xBA38;&#xC785;&#xB2C8;&#xB2E4;. &#xC5B4;&#xB514; &#xADFC;&#xC721;&#xC740; &#xCE94;&#xD2F8;&#xB808;&#xBC84;&#xC5D0; &#xC791;&#xB3D9; &#xD558; &#xACE0; &#xC0DD;&#xC131; &#xD558;&#xB294; &#xD798;&#xC744; &#xCE21;&#xC815; &#xC7A5;&#xCE58; &#xC870;&#xB9BD; &#xB418;&#xC5C8;&#xC2B5;&#xB2C8;&#xB2E4;. &#xC5D0; &#xACB0;&#xD569; &#xB41C; &#xD654;&#xD559; &#xBC1C;&#xC9C4;&#xAE30;&#xAC00; &#xC81C;&#xACF5; &#xD558;&#xB294; &#xBB34;&#xB8CC; &#xC2E4;&#xD589; &#xD654;&#xD559; &#xBAA8;&#xD130; &#xD53C;&#xD06C; &#xC804;&#xB825; 20 mW kg(-1)&#xC758; &#xC9C1;&#xB82C; 10 nm &#xBAA8;&#xC591; &#xCD94;&#xAC00; &#xD558; &#xC5EC; &#xC0DD;&#xC131; &#xD558;&#xB294; &#xBCC0;&#xACBD;&#xC5D0; &#xC774;&#xC0C1; 5 &#xBC30;&#xB098; &#xD06C;&#xAE30;&#xAC00; &#xC870;&#xC815; &#xB429;&#xB2C8;&#xB2E4;. &#xC720;&#xC0AC; &#xBCC0;&#xD615;, &#xD655;&#xC7A5; &#xAC00;&#xB2A5;&#xD55C; &#xADFC;&#xC721; &#xC7A5;&#xCE58; &#xAC74;&#xC124;&#xC744; &#xC704;&#xD55C; &#xAC15;&#xB825;&#xD55C; &#xC791;&#xC5C5; &#xC18C;&#xC7AC;&#xC5D0; &#xACB0;&#xACFC; &#xD558; &#xC824;&#xC758; nanostructured &#xBCF8;&#xC9C8; &#xC774;&#xB2E4;.

&#xD654;&#xD559;&#xC801;&#xC73C;&#xB85C; &#xC81C;&#xC5B4; &#xD569;&#xC131; &#xADFC;&#xC721;&#xC5D0; &#xC655;&#xBCF5; &#xBC1C;&#xC804;.

Se ha construido un m&uacute;sculo sint&eacute;tico escalable que transducts nanoscale molecular forma cambia en movimiento macrosc&oacute;pico. El material de trabajo, que deforma affinely en respuesta a un est&iacute;mulo de pH, es un copol&iacute;mero de bloque autoensambladas que comprende los dominios hidrof&oacute;bicos nanosc&oacute;picas en una matriz polyacid d&eacute;bil. Un dispositivo ha sido ensamblado donde el m&uacute;sculo funciona en un voladizo y se ha medido la fuerza generada. Cuando se acopla a un oscilador qu&iacute;mico proporciona un motor de funcionamiento qu&iacute;mico libre que genera una potencia pico de 20 mW kilogramo a&ntilde;adiendo serial 10 forma nm cambia escalas en 5 &oacute;rdenes de magnitud. Es la naturaleza nanoestructurados del gel que da lugar a la deformaci&oacute;n af&iacute;n y resultados en un robusto material de trabajo para la construcci&oacute;n de dispositivos escalables muscular.

Generaci&oacute;n de energ&iacute;a alternativo en un m&uacute;sculo sint&eacute;tico qu&iacute;micamente conducido.

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&#x81EA;&#x6211;&#x80FD;&#x52A8;&#x6027;&#x80F6;&#x4F53;&#x7C92;&#x5B50;&#xFF1A; &#x4ECE;&#x5B9A;&#x5411;&#x5230;&#x968F;&#x673A;&#x6E38;&#x8D70;&#x7684;&#x63A8;&#x8FDB;&#x3002;

The motion of an artificial microscale swimmer that uses a chemical reaction catalyzed on its own surface to achieve autonomous propulsion is fully characterized experimentally. It is shown that at short times it has a substantial component of directed motion, with a velocity that depends on the concentration of fuel molecules. At longer times, the motion reverts to a random walk with a substantially enhanced diffusion coefficient. Our results suggest strategies for designing artificial chemotactic systems.

Self-motile colloidal particles: from directed propulsion to random walk.

Le mouvement d&#39;un nageur de micro-&eacute;chelle artificiel qui utilise une r&eacute;action chimique catalys&eacute;e sur sa propre surface pour atteindre propulsion autonome est enti&egrave;rement caract&eacute;ris&eacute; exp&eacute;rimentalement. Il est montr&eacute; qu&#39;aux temps courts, il a une composante importante du mouvement dirig&eacute;, avec une vitesse qui d&eacute;pend de la concentration des mol&eacute;cules de carburant. &Agrave; des temps plus longs, le mouvement revient &agrave; une marche al&eacute;atoire avec un coefficient de diffusion sensiblement am&eacute;lior&eacute;e. Nos r&eacute;sultats sugg&egrave;rent des strat&eacute;gies pour la conception de syst&egrave;mes artificiels de chimiotactiques.

Les particules collo&iuml;dales auto mobile : de dirige la propulsion de la marche al&eacute;atoire.

Die Bewegung von einem k&uuml;nstlichen Microscale-Schwimmer, die eine chemische Reaktion katalysiert auf seiner eigenen Oberfl&auml;che verwendet, um die autonomen Antrieb zu erreichen ist vollst&auml;ndig experimentell gekennzeichnet. Es ist bewiesen, dass zu kurze Zeiten es einen wesentlichen Bestandteil der gerichteten Bewegung, mit einer Geschwindigkeit, die von der Konzentration der Kraftstoff Molek&uuml;le abh&auml;ngt. Zu l&auml;ngeren Zeiten wird die Bewegung auf ein Zufallsmarkt mit einer wesentlich verbesserten Diffusionskoeffizient zur&uuml;ckgesetzt. Unsere Ergebnisse legen nahe, Strategien f&uuml;r das Entwerfen von k&uuml;nstlichen chemotaktische Systeme.

Selbst-st&auml;bchenf&ouml;rmiges kolloidalen Teilchen: Antrieb auf Random-Walk leitete.

Il movimento di un nuotatore di Microscala artificiale che utilizza una reazione chimica catalizzata sulla propria superficie per ottenere propulsione autonoma &egrave; completamente caratterizzato sperimentalmente. &Egrave; dimostrato che in tempi brevi ha una componente sostanziale del moto diretto, con una velocit&agrave; che dipende dalla concentrazione delle molecole di carburante. In tempi pi&ugrave; lunghi, il movimento viene ripristinato un random walk con un coefficiente di diffusione sostanzialmente migliorata. I nostri risultati suggeriscono strategie per la progettazione di sistemi artificiali chemiotattici.

Self-motili particelle colloidali: dalla regia propulsione a random walk.

&#x89E6;&#x5A92;&#x5316;&#x5B66;&#x53CD;&#x5FDC;&#x8868;&#x9762;&#x306B;&#x81EA;&#x5F8B;&#x63A8;&#x9032;&#x3092;&#x9054;&#x6210;&#x3059;&#x308B;&#x305F;&#x3081;&#x306B;&#x4F7F;&#x7528;&#x3059;&#x308B;&#x4EBA;&#x5DE5;&#x30DE;&#x30A4;&#x30AF;&#x30ED; &#x30B9;&#x30B1;&#x30FC;&#x30EB; &#x30B9;&#x30A4;&#x30DE;&#x30FC;&#x306E;&#x904B;&#x52D5;&#x306F;&#x3001;&#x5B8C;&#x5168;&#x306B;&#x5B9F;&#x9A13;&#x7684;&#x7279;&#x5FB4;&#x3067;&#x3059;&#x3002;&#x77ED;&#x6642;&#x9593;&#x3067;&#x305D;&#x308C;&#x306F;&#x71C3;&#x6599;&#x5206;&#x5B50;&#x306E;&#x6FC3;&#x5EA6;&#x306B;&#x4F9D;&#x5B58;&#x3057;&#x3066;&#x3044;&#x308B;&#x901F;&#x5EA6;&#x3068;&#x65B9;&#x5411;&#x306E;&#x904B;&#x52D5;&#x306E;&#x76F8;&#x5F53;&#x306A;&#x90E8;&#x54C1;&#x3092;&#x6301;&#x3064;&#x3053;&#x3068;&#x3092;&#x793A;&#x3057;&#x307E;&#x3059;&#x3002;&#x9577;&#x3044;&#x56DE;&#x3067;&#x306F;&#x3001;&#x904B;&#x52D5;&#x5927;&#x5E45;&#x306B;&#x5F37;&#x5316;&#x3055;&#x308C;&#x305F;&#x62E1;&#x6563;&#x4FC2;&#x6570;&#x3068;&#x30E9;&#x30F3;&#x30C0;&#x30E0;&#x30A6;&#x30A9;&#x30FC;&#x30AF;&#x306B;&#x623B;&#x308A;&#x307E;&#x3059;&#x3002;&#x4EBA;&#x5DE5;&#x306E;&#x8D70;&#x5316;&#x6027;&#x30B7;&#x30B9;&#x30C6;&#x30E0;&#x306E;&#x8A2D;&#x8A08;&#x6226;&#x7565;&#x304C;&#x793A;&#x5506;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;

&#x81EA;&#x5DF1;&#x904B;&#x52D5;&#x306E;&#x30B3;&#x30ED;&#x30A4;&#x30C9;&#x7C92;&#x5B50;: &#x304B;&#x3089;&#x30E9;&#x30F3;&#x30C0;&#x30E0; &#x30FB; &#x30A6;&#x30A9;&#x30FC;&#x30AF;&#x306B;&#x63A8;&#x9032;&#x3092;&#x76E3;&#x7763;&#x3057;&#x307E;&#x3059;&#x3002;

&#xC790;&#xC728; &#xCD94;&#xC9C4; &#xB2EC;&#xC131; &#xD558;&#xAE30; &#xC704;&#xD574; &#xC790;&#xCCB4; &#xD45C;&#xBA74;&#xC5D0; &#xD654;&#xD559; &#xBC18;&#xC751; &#xCD09;&#xB9E4;&#xB97C; &#xC0AC;&#xC6A9; &#xD558;&#xB294; &#xC778;&#xACF5; microscale &#xC218;&#xC601; &#xBAA8;&#xC158;&#xC740; &#xC644;&#xBCBD; &#xD558; &#xAC8C; &#xC2E4;&#xD5D8;&#xC801;&#xC73C;&#xB85C; &#xD2B9;&#xC9D5;&#xC785;&#xB2C8;&#xB2E4;. &#xC9E7;&#xC740; &#xC2DC;&#xAC04;&#xC5D0; &#xADF8;&#xAC83;&#xC740; &#xC5F0;&#xB8CC; &#xBD84;&#xC790;&#xC758; &#xB18D;&#xB3C4;&#xC5D0; &#xB530;&#xB77C; &#xC18D;&#xB3C4;&#xC640; &#xAC10;&#xB3C5; &#xC6B4;&#xB3D9;&#xC758; &#xC2E4;&#xC9C8;&#xC801;&#xC778; &#xAD6C;&#xC131; &#xC694;&#xC18C;&#xAC00; &#xD45C;&#xC2DC; &#xB429;&#xB2C8;&#xB2E4;. &#xB354; &#xC774;&#xC0C1; &#xC2DC;&#xAC04;&#xC5D0; &#xBAA8;&#xC158; &#xC2E4;&#xC9C8;&#xC801;&#xC73C;&#xB85C; &#xD5A5;&#xC0C1; &#xB41C; &#xD655;&#xC0B0; &#xACC4;&#xC218;&#xB294; &#xB79C;&#xB364; &#xC6CC;&#xD06C; &#xB418;&#xB3CC;&#xC544;&#xAC11;&#xB2C8;&#xB2E4;. &#xC6B0;&#xB9AC;&#xC758; &#xACB0;&#xACFC; &#xC778;&#xACF5; &#xD608; &#xC2DC;&#xC2A4;&#xD15C; &#xC124;&#xACC4;&#xB97C; &#xC704;&#xD55C; &#xC804;&#xB7B5;&#xC744; &#xC81C;&#xC548; &#xD569;&#xB2C8;&#xB2E4;.

&#xC790;&#xAE30; &#xC6B4;&#xB3D9; &#xCF5C; &#xB85C;&#xC774;&#xB4DC; &#xC785;&#xC790;:&#xC5D0;&#xC11C; &#xAC10;&#xB3C5; &#xB79C;&#xB364; &#xC6CC;&#xD06C;&#xB97C; &#xCD94;&#xC9C4;.

El movimiento de un nadador de microescala artificial que usa una reacci&oacute;n qu&iacute;mica catalizada en su propia superficie para lograr la propulsi&oacute;n aut&oacute;noma se caracteriza completamente experimental. Se demuestra que en tiempos cortos tiene un componente substancial del movimiento dirigido, con una velocidad que depende de la concentraci&oacute;n de las mol&eacute;culas del combustible. En tiempos m&aacute;s largos, el movimiento vuelve a un paseo aleatorio con un coeficiente de difusi&oacute;n substancialmente mejorada. Nuestros resultados sugieren estrategias para dise&ntilde;ar sistemas quimiot&aacute;cticos artificiales.

Uno mismo-motile part&iacute;culas coloidales: propulsi&oacute;n a paseo aleatorio dirigido.

Floating supported bilayers (FSBs) are new systems which have emerged over the past few years to produce supported membrane mimics, where the bilayers remain associated with the substrate, but are cushioned from the substrates constraining influence by a large hydration layer. In this paper we describe a new approach to fabricating FSBs using a chemically grafted phospholipid layer as the support for the floating membrane. The grafted lipid layer was produced using a Langmuir-Schaeffer transfer of acryloyl-functionalized lipid onto a pre-prepared substrate, with AIBN-induced cross-polymerization to permanently bind the lipids in place. A bilayer of DSPC was then deposited onto this grafted monolayer using a combination of Langmuir-Blodgett and Langmuir-Schaeffer transfer. The resulting system was characterized by neutron reflection under two water contrasts, and we show that the new system shows a hydrating layer of approximately 17.5 A in the gel phase, which is comparable to previously described FSB systems. We provide evidence that the grafted substrate is reusable after cleaning and suggest that this greatly simplifies the fabrication and characterization of FSBs compared to previous methods.

Floating lipid bilayers deposited on chemically grafted phosphatidylcholine surfaces.

Unilamellar &#x805A;&#x5408;&#x7269;&#x56CA;&#x6CE1;&#x5F62;&#x6210;&#x65F6;&#x5D4C;&#x6BB5;&#x5171;&#x805A;&#x7269;&#x81EA;&#x4EA7;&#x8FD9;&#x79CD;&#x8981;&#x4E0A;&#x5F62;&#x6210;&#x5355;&#x4E00;&#x7684;&#x53CC;&#x5C42;&#x7ED3;&#x6784;&#xFF0C;&#x5177;&#x6709;&#x758F;&#x6C34;&#x6027;&#x7684;&#x6838;&#x5FC3;&#x548C;&#x4EB2;&#x6C34;&#x6027;&#x8868;&#x9762;&#x548C;&#x7531;&#x6B64;&#x4EA7;&#x751F;&#x7684;&#x819C;&#x6298;&#x53E0;&#x548C;&#x901A;&#x8FC7;&#x8FDE;&#x63A5;&#x5176;&#x8FB9;&#x7F18;&#x62EC;&#x8D77;&#x7A7A;&#x95F4;&#x8FDB;&#x884C;&#x91CD;&#x65B0;&#x6392;&#x5217;&#x3002;&#x7269;&#x7406;&#x5B66;&#x7684;&#x81EA;&#x7EC4;&#x88C5;&#x7D27;&#x6307;&#x5B9A;&#x7684;&#x7ED3;&#x679C;&#x56CA;&#x6CE1;&#xFF0C;&#x5899;&#x4F53;&#x539A;&#x5EA6;&#xFF0C;&#x4F46;&#x65E2;&#x4E3A;&#x805A;&#x5408;&#x7269;&#x56CA;&#x6CE1;&#x548C;&#x78F7;&#x8102;&#xFF0C;&#x6CA1;&#x6709;&#x673A;&#x5236;&#x5F3A;&#x70C8;&#x9009;&#x62E9;&#x7684;&#x6574;&#x4F53;&#x5927;&#x5C0F;&#xFF0C;&#x6240;&#x4EE5;&#x5C3A;&#x5BF8;&#x5206;&#x5E03;&#x7684;&#x56CA;&#x6CE1;&#x5F80;&#x5F80;&#x662F;&#x5F88;&#x591A;&#x5206;&#x6563;&#x3002;&#x6211;&#x4EEC;&#x62A5;&#x544A;&#x751F;&#x4EA7;&#x63A7;&#x5236;&#x7684;&#x5927;&#x5C0F;&#x5206;&#x5E03;&#x7684;&#x5FAE;&#x7C73;&#x5927;&#x5C0F;&#x7684;&#x4E00;&#x79CD;&#x65B9;&#x6CD5; &#xFF08;&#x5373;&#xFF0C;&#x5DE8;) &#x56CA;&#x6CE1;&#x7684;&#x5149;&#x523B;&#x6280;&#x672F;&#x7ED3;&#x5408; &#39;&#x81EA;&#x4E0A;&#x800C;&#x4E0B;&#39; &#x63A7;&#x5236;&#x7684;&#x5FAE;&#x7C73;&#x5C3A;&#x5BF8;&#x7684;&#x7279;&#x6027; &#xFF08;&#x56CA;&#x6CE1;&#x76F4;&#x5F84;&#xFF09; &#x548C;&#x901A;&#x8FC7;&#x5206;&#x5B50;&#x81EA;&#x7EC4;&#x88C5;&#x7EB3;&#x7C73;&#x5C3A;&#x5BF8;&#x7684;&#x7279;&#x6027; (&#x819C;&#x539A;&#x5EA6;) &#x7684;&#x81EA;&#x4E0B;&#x800C;&#x4E0A;&#x63A7;&#x5236;&#x4E0E;&#x964D;&#x6E29;&#x3002;&#x5B83;&#x4F7F;&#x7A84;&#x5206;&#x5E03;&#x6240;&#x80FD;&#x627E;&#x5230;&#x7684;&#x5E94;&#x7528;&#x7A0B;&#x5E8F;&#x5728;&#x836F;&#x7269;&#x548C;&#x57FA;&#x56E0;&#x8F7D;&#x4F53;&#x3001; &#x7EB3;&#x7C73;&#x548C;&#x5FAE;&#x578B;&#x53CD;&#x5E94;&#x5806;&#x3001; &#x57FA;&#x8D28;&#x751F;&#x7269;&#x5927;&#x5206;&#x5B50;&#x6676;&#x4F53;&#x5B66;&#x548C;&#x6A21;&#x578B;&#x7CFB;&#x7EDF;&#x7814;&#x7A76;&#x4FC3;&#x8FDB;&#x819C;&#x529F;&#x80FD;&#x7684; unilamellar &#x56CA;&#x6CE1;&#x81EA;&#x53D1;&#x5F62;&#x6210;&#x3002;

&#x6A21;&#x677F;&#x5316;&#x5F62;&#x6210;&#x7684;&#x5DE8;&#x578B;&#x805A;&#x5408;&#x7269;&#x56CA;&#x6CE1;&#x4E0E;&#x63A7;&#x5236;&#x7684;&#x5927;&#x5C0F;&#x5206;&#x5E03;&#x3002;

Unilamellar polymer vesicles are formed when a block copolymer self-assembles to form a single bilayer structure, with a hydrophobic core and hydrophilic surfaces, and the resulting membrane folds over and rearranges by connecting its edges to enclose a space. The physics of self-assembly tightly specifies the wall thickness of the resulting vesicle, but, both for polymer vesicles and phospholipids, no mechanism strongly selects for the overall size, so the size distribution of vesicles tends to be very polydisperse. We report a method for the production of controlled size distributions of micrometre-sized (that is, giant) vesicles combining the 'top-down' control of micrometre-sized features (vesicle diameter) by photolithography and dewetting with the 'bottom-up' control of nanometre-sized features (membrane thickness) by molecular self-assembly. It enables the spontaneous creation of unilamellar vesicles with a narrow size distribution that could find applications in drug and gene delivery, nano- and micro-reactors, substrates for macromolecular crystallography and model systems for studies of membrane function.

Templated formation of giant polymer vesicles with controlled size distributions.

Les v&eacute;sicules unilamellaires polym&egrave;re sont forment lorsqu&#39;un copolym&egrave;re &agrave; blocs est pour former une structure bicouche unique, avec un noyau hydrophobe des surfaces hydrophiles et les plis de la membrane qui en r&eacute;sulte au fil et r&eacute;organise ses bords pour enfermer un espace en vous connectant. La physique d&#39;auto-assemblage &eacute;troitement sp&eacute;cifie l&#39;&eacute;paisseur de la paroi de la v&eacute;sicule qui en r&eacute;sulte, mais, aussi bien pour les phospholipides et les v&eacute;sicules de polym&egrave;re, aucun m&eacute;canisme ne s&eacute;lectionne fortement pour la taille globale, alors que la distribution de taille des v&eacute;sicules tend &agrave; &ecirc;tre tr&egrave;s polydispers&eacute;s. Nous pr&eacute;sentons une m&eacute;thode pour la production d&#39;une distribution contr&ocirc;l&eacute;e taille taille microm&egrave;tre (c&#39;est-&agrave;-dire, g&eacute;ant) v&eacute;sicules combinant le contr&ocirc;le &quot;top-down&quot; de fonctionnalit&eacute;s microm&egrave;tre taille (diam&egrave;tre de la v&eacute;sicule) par photolithographie et d&eacute;shydratation avec le contr&ocirc;le &laquo; bottom-up &raquo; des fonctionnalit&eacute;s nanom&egrave;tres (&eacute;paisseur de la membrane) par mol&eacute;culaire auto-assemblage. Il permet la cr&eacute;ation spontan&eacute;e de v&eacute;sicules unilamellaires avec une granulom&eacute;trie &eacute;troite qui pourrait trouver des applications dans la drogue et livraison de g&egrave;ne, nano - et micro-r&eacute;acteurs, substrats pour la cristallographie macromol&eacute;culaire et syst&egrave;mes de mod&egrave;les pour les &eacute;tudes de fonction de la membrane.

Bas&eacute; sur un mod&egrave;le formation de v&eacute;sicules polym&egrave;res g&eacute;ant avec des distributions de taille contr&ocirc;l&eacute;e.

Unilamellar Polymer Bl&auml;schen entstehen, wenn ein Blockcopolymer self-assembles um &uuml;ber eine einzelne Bilayer Struktur, einen hydrophoben Kern und hydrophile Oberfl&auml;chen und die resultierende Membran-Falten bilden und ordnet durch die Verbindung von seinen R&auml;ndern um einen Raum umschlie&szlig;en. Die Physik der Selbstorganisation eng gibt die Wandst&auml;rke des resultierenden Vesikel, doch sowohl f&uuml;r Polymer-Bl&auml;schen und Phospholipide, keinen Mechanismus stark w&auml;hlt f&uuml;r die Gesamtgr&ouml;&szlig;e, so dass die Gr&ouml;&szlig;enverteilung von Vesikeln tendenziell sehr Polydisperse. Wir berichten &uuml;ber eine Methode zur Herstellung von kontrollierten Gr&ouml;&szlig;e Verteilungen von Mikrometer Gr&ouml;&szlig;e (d. h. Riese) Bl&auml;schen kombinieren das &#39;Top-Down&#39;-Steuerelement-Mikrometer-kleine Features (Vesikel Durchmesser) durch Fotolithografie und Entnetzung mit dem &#39;Bottom-Up&#39;-Steuerelement-Nanometer-kleine Features (Dicke der Membran) durch molekulare Selbstassemblierung. Es erm&ouml;glicht die spontane Erstellung Unilamellar Bl&auml;schen mit einer engen Gr&ouml;&szlig;enverteilung, die Anwendungen in Drogen und gen-Lieferung, Nano - und Mikro-Reaktoren, Substrate f&uuml;r Makromolekulare Kristallographie und Modellsysteme f&uuml;r Studien der Membran-Funktion finden konnte.

Auf Vorlagen basierende Bildung von riesigen Polymer Bl&auml;schen mit kontrollierten Gr&ouml;&szlig;e Distributionen.

Le vescicole di polimero unilamellari sono formate quando un copolimero a blocchi self-assembles per formare una struttura doppio strato singolo, con un nucleo idrofobo e superfici idrofile e le pieghe di membrana risultante sopra e riorganizza collegando i bordi per racchiudere uno spazio. La fisica di autoassemblaggio strettamente specifica lo spessore della parete della vescicola risultante, ma, sia per fosfolipidi e vescicole polimeriche, nessun meccanismo fortemente seleziona per le dimensioni complessive, cos&igrave; la distribuzione delle dimensioni delle vescicole tende ad essere molto polidispersi. Riportiamo un metodo per la produzione di distribuzioni di dimensione controllata di micrometro di dimensioni medie (cio&egrave;, gigante) vescicole che combina il controllo &#39;top-down&#39; di micrometri-dimensioni caratteristiche (diametro della vescicola) di fotolitografia e bagnabilit&agrave; con il controllo &#39;bottom-up&#39; di nanometro-dimensioni caratteristiche (spessore membrana) da molecolare auto-assemblaggio. Esso consente la creazione spontanea di vescicole unilamellari con una distribuzione di dimensione stretta che potrebbe trovare applicazioni in droga e consegna del gene, nano - e micro-reattori, substrati per la cristallografia macromolecolare e sistemi modello per gli studi di funzione di membrana.

Basato su formazione di vescicole giganti polimero con distribuzioni granulometriche controllate.

&#x30D6;&#x30ED;&#x30C3;&#x30AF;&#x5171;&#x91CD;&#x5408;&#x4F53;&#x4E0A;&#x758E;&#x6C34;&#x6027;&#x30B3;&#x30A2;&#x3068;&#x89AA;&#x6C34;&#x6027;&#x8868;&#x9762;&#x3068;&#x819C;&#x895E;&#x306E;&#x7D50;&#x679C;&#x306E;&#x5358;&#x4E00;&#x306E; 2 &#x5C64;&#x69CB;&#x9020;&#x3092;&#x5F62;&#x6210;&#x3059;&#x308B;&#x62E1;&#x5F35;&#x3057;&#x3001;&#x30B9;&#x30DA;&#x30FC;&#x30B9;&#x3092;&#x56F2;&#x3080;&#x305F;&#x3081;&#x306E;&#x7AEF;&#x3092;&#x63A5;&#x7D9A;&#x3059;&#x308B;&#x3053;&#x3068;&#x306B;&#x3088;&#x3063;&#x3066;&#x4E26;&#x3079;&#x66FF;&#x3048;&#x307E;&#x3059;&#x9AD8;&#x5206;&#x5B50;&#x819C;&#x30EA;&#x30DD;&#x30BD;&#x30FC;&#x30E0;&#x304C;&#x5F62;&#x6210;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002;&#x7269;&#x7406;&#x5B66;&#x306E;&#x81EA;&#x5DF1;&#x3057;&#x3063;&#x304B;&#x308A;&#x3068;&#x7D50;&#x679C;&#x306E;&#x5C0F;&#x80DE;&#x306E;&#x58C1;&#x306E;&#x539A;&#x3055;&#x3092;&#x6307;&#x5B9A;&#x3057;&#x307E;&#x3059;&#x304C;&#x3001;&#x5C0F;&#x80DE;&#x306E;&#x30B5;&#x30A4;&#x30BA;&#x5206;&#x5E03;&#x306F;&#x975E;&#x5E38;&#x306B;&#x591A;&#x5206;&#x6563;&#x3059;&#x308B;&#x50BE;&#x5411;&#x304C;&#x3042;&#x308B;&#x306E;&#x3067;&#x4E21;&#x65B9;&#x306E;&#x30DD;&#x30EA;&#x30DE;&#x30FC;&#x5C0F;&#x80DE;&#x3068;&#x30EA;&#x30F3;&#x8102;&#x8CEA;&#x3001;&#x30E1;&#x30AB;&#x30CB;&#x30BA;&#x30E0;&#x5F37;&#x304F;&#x5168;&#x4F53;&#x306E;&#x30B5;&#x30A4;&#x30BA;&#x3092;&#x9078;&#x629E;&#x3055;&#x308C;&#x307E;&#x305B;&#x3093;&#x3002;&#x6211;&#x3005; &#x306F;&#x30DE;&#x30A4;&#x30AF;&#x30ED; &#x30E1;&#x30FC;&#x30C8;&#x30EB; &#x30B5;&#x30A4;&#x30BA;&#x306E;&#x5236;&#x5FA1;&#x3055;&#x308C;&#x305F;&#x30B5;&#x30A4;&#x30BA;&#x5206;&#x5E03;&#x306E;&#x88FD;&#x9020;&#x65B9;&#x6CD5;&#x3092;&#x5831;&#x544A; &#xFF08;&#x3064;&#x307E;&#x308A;&#x3001;&#x5DE8;&#x5927;&#x306A;&#xFF09; &#x30D5;&#x30A9;&#x30C8;&#x30EA;&#x30BD;&#x30B0;&#x30E9;&#x30D5;&#x30A3;&#x306B;&#x3088;&#x308B;&#x30DE;&#x30A4;&#x30AF;&#x30ED; &#x30E1;&#x30FC;&#x30C8;&#x30EB; &#x30B5;&#x30A4;&#x30BA;&#x306E;&#x6A5F;&#x80FD; (&#x5C0F;&#x80DE;&#x5F84;) &#x306E; &#39;&#x30C8;&#x30C3;&#x30D7;&#x30C0;&#x30A6;&#x30F3;&#39; &#x5236;&#x5FA1;&#x3092;&#x7D44;&#x307F;&#x5408;&#x308F;&#x305B;&#x308B;&#x3053;&#x3068;&#x3068;&#x3092;&#x30CA;&#x30CE;&#x30E1;&#x30FC;&#x30C8;&#x30EB; &#x30B5;&#x30A4;&#x30BA;&#x306E;&#x6A5F;&#x80FD; (&#x819C;&#x539A;) &#x306E; &#39;&#x30DC;&#x30C8;&#x30E0;&#x30A2;&#x30C3;&#x30D7;&#39; &#x5236;&#x5FA1;&#x3092;&#x81EA;&#x5DF1;&#x7D44;&#x7E54;&#x5316;&#x5206;&#x5B50;&#x306B;&#x3088;&#x3063;&#x3066;&#x30C7;&#x30A3;&#x30A6;&#x30A7;&#x30C3;&#x30C6;&#x30A3;&#x30F3;&#x30B0;&#x5C0F;&#x80DE;&#x3002;&#x85AC;&#x7269;&#x30FB;&#x907A;&#x4F1D;&#x5B50;&#x30C7;&#x30EA;&#x30D0;&#x30EA;&#x30FC;&#x3001;&#x30CA;&#x30CE; &#x30FB; &#x30DE;&#x30A4;&#x30AF;&#x30ED;&#x539F;&#x5B50;&#x7089;&#x3001;&#x57FA;&#x677F;&#x9AD8;&#x5206;&#x5B50;&#x7D50;&#x6676;&#x5B66;&#x3068;&#x819C;&#x6A5F;&#x80FD;&#x306E;&#x30E2;&#x30C7;&#x30EB; &#x30B7;&#x30B9;&#x30C6;&#x30E0;&#x7814;&#x7A76;&#x306E;&#x305F;&#x3081;&#x306B;&#x30A2;&#x30D7;&#x30EA;&#x30B1;&#x30FC;&#x30B7;&#x30E7;&#x30F3;&#x3092;&#x898B;&#x3064;&#x3051;&#x308B;&#x3053;&#x3068;&#x304C;&#x3067;&#x304D;&#x308B;&#x72ED;&#x3044;&#x30B5;&#x30A4;&#x30BA;&#x5206;&#x5E03;&#x3068;&#x8102;&#x8CEA;&#x819C;&#x30EA;&#x30DD;&#x30BD;&#x30FC;&#x30E0;&#x306E;&#x81EA;&#x767A;&#x7684;&#x306A;&#x5275;&#x9020;&#x3067;&#x304D;&#x307E;&#x3059;&#x3002;

&#x30B3;&#x30F3;&#x30C8;&#x30ED;&#x30FC;&#x30EB;&#x306E;&#x30B5;&#x30A4;&#x30BA;&#x5206;&#x5E03;&#x3092;&#x6301;&#x3064;&#x5DE8;&#x5927;&#x306A;&#x9AD8;&#x5206;&#x5B50;&#x30D9;&#x30B7;&#x30AF;&#x30EB;&#x306E; template &#x5BA3;&#x8A00;&#x3055;&#x308C;&#x305F;&#x5F62;&#x6210;&#x3002;

Unilamellar &#xD3F4;&#xB9AC;&#xBA38; &#xC18C;&#xD3EC;&#xB294; &#xBE14;&#xB85D; &#xCF54; &#xD3F4;&#xB9AC;&#xBA38; self-assembles &#xC774;&#xC0C1;&#xC758; &#xC18C;&#xC218; &#xCF54;&#xC5B4; &#xBC0F; &#xCE5C;&#xC218;&#xC131; &#xD45C;&#xBA74;&#xACFC; &#xACB0;&#xACFC; &#xB9C9; &#xC8FC;&#xB984;&#xC73C;&#xB85C; &#xB2E8;&#xC77C; bilayer &#xAD6C;&#xC870;&#xB97C; &#xD615;&#xC131; &#xD558; &#xACE0; &#xACF5;&#xAC04;&#xC744; &#xADF8;&#xAC83;&#xC758; &#xAC00;&#xC7A5;&#xC790;&#xB9AC;&#xB97C; &#xC5F0;&#xACB0; &#xD558; &#xC5EC; &#xB2E4;&#xC2DC; &#xC815;&#xB82C; &#xB420; &#xB54C; &#xD615;&#xC131; &#xB41C;&#xB2E4;. &#xBB3C;&#xB9AC;&#xD559;&#xC758; &#xC790;&#xAE30; &#xC870;&#xB9BD; &#xB2E8;&#xB2E8;&#xD788; &#xACB0;&#xACFC; &#xAE30;&#xC758; &#xBCBD; &#xB450;&#xAED8; &#xC9C0;&#xC815; &#xD558;&#xC9C0;&#xB9CC; &#xBAA8;&#xB450; &#xD3F4;&#xB9AC;&#xBA38; &#xC18C;&#xD3EC; &#xBC0F; &#xC778;&#xC9C0;&#xC9C8;, &#xBA54;&#xCEE4;&#xB2C8;&#xC998;&#xC774; &#xAC15;&#xD558;&#xAC8C; &#xC120;&#xD0DD; &#xC804;&#xCCB4; &#xD06C;&#xAE30;&#xC5D0; &#xB300; &#xD55C; &#xC18C;&#xD3EC; &#xD06C;&#xAE30; &#xBD84;&#xD3EC;&#xB294; &#xB9E4;&#xC6B0; polydisperse &#xACBD;&#xD5A5;&#xC774; &#xADF8;&#xB798;&#xC11C;. &#xC6B0;&#xB9AC; &#xBCF4;&#xACE0; &#xB9C8;&#xC774;&#xD06C;&#xB85C;&#xBBF8;&#xD130; &#xD06C;&#xAE30;&#xC758; &#xC81C;&#xC5B4; &#xD06C;&#xAE30; &#xBD84;&#xD3EC;&#xC758; &#xC0DD;&#xC0B0; &#xD558;&#xB294; &#xBC29;&#xBC95; (&#xC989;, &#xAC70; &#xB300; &#xD55C;) &#xD3EC;&#xD1A0; &#xB9AC;&#xC18C; &#xADF8;&#xB798;&#xD53C;&#xC5D0; &#xC758;&#xD574; &#xB9C8;&#xC774;&#xD06C;&#xB85C;&#xBBF8;&#xD130; &#xD06C;&#xAE30;&#xC758; &#xAE30;&#xB2A5; (&#xAE30; &#xC9C1;&#xACBD;)&#xC758; &#39; &#xD1B1; &#xB2E4;&#xC6B4; &#39; &#xCEE8;&#xD2B8;&#xB864;&#xC744; &#xACB0;&#xD569; &#xD558; &#xACE0; &#xC790;&#xAE30; &#xC870;&#xB9BD; &#xBD84;&#xC790; &#xD558; &#xC5EC; &#xB098;&#xB178;&#xBBF8;&#xD130; &#xD06C;&#xAE30;&#xC758; &#xAE30;&#xB2A5; (&#xB9C9; &#xB450;&#xAED8;)&#xC758; &#39; &#xC0C1;&#xD5A5;&#xC2DD; &#39; &#xCEE8;&#xD2B8;&#xB864;&#xACFC; dewetting &#xC18C;&#xD3EC;. &#xADF8;&#xAC83;&#xC740; &#xC57D;&#xBB3C; &#xBC0F; &#xC720;&#xC804;&#xC790; &#xC804;&#xB2EC;, &#xB098;&#xB178; &#xBC0F; &#xB9C8;&#xC774;&#xD06C;&#xB85C; &#xC6D0;&#xC790;&#xB85C;, &#xAE30;&#xD310;&#xC5D0; &#xACE0;&#xBD84;&#xC790; &#xACB0;&#xC815;&#xD559; &#xBC0F; &#xB9C9; &#xAE30;&#xB2A5; &#xC5F0;&#xAD6C;&#xB97C; &#xC704;&#xD55C; &#xBAA8;&#xB378; &#xC2DC;&#xC2A4;&#xD15C;&#xC744; &#xC704;&#xD55C; &#xC751;&#xC6A9; &#xD504;&#xB85C;&#xADF8;&#xB7A8;&#xC744; &#xCC3E;&#xC744; &#xC218; &#xC788;&#xB294; &#xC881;&#xC740; &#xD06C;&#xAE30; &#xBD84;&#xD3EC;&#xC640; unilamellar vesicles &#xC790;&#xBC1C;&#xC801;&#xC73C;&#xB85C; &#xB9CC;&#xB4E4; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;.

&#xC81C;&#xC5B4; &#xB41C; &#xD06C;&#xAE30; &#xBD84;&#xD3EC;&#xC640; &#xAC70; &#xB300; &#xD55C; &#xD3F4;&#xB9AC;&#xBA38; &#xC18C;&#xD3EC;&#xC758; &#xD15C;&#xD50C;&#xB9BF; &#xAE30;&#xBC18; &#xD615;&#xC131;.

Las ves&iacute;culas de pol&iacute;mero unilaminar se forman cuando un copol&iacute;mero en bloque self-assembles para formar una estructura &uacute;nica bicapa, con un n&uacute;cleo hidrof&oacute;bico y superficies hidrof&iacute;licas y los pliegues de membrana resultante sobre y reorganiza conectando sus bordes para incluir un espacio. La f&iacute;sica de Automontaje firmemente especifica el grosor de la pared de la ves&iacute;cula resultante, pero, tanto para los fosfol&iacute;pidos y ves&iacute;culas de pol&iacute;mero, ning&uacute;n mecanismo fuertemente selecciona para el tama&ntilde;o total, por lo que la distribuci&oacute;n de tama&ntilde;o de las ves&iacute;culas tiende a ser muy polidispersas. Se presenta un m&eacute;todo para la producci&oacute;n de distribuciones de tama&ntilde;o controlado de tama&ntilde;o micr&oacute;metros (es decir, gigante) ves&iacute;culas combina el control de &quot;top-down&quot; de caracter&iacute;sticas medianas en micr&oacute;metros (di&aacute;metro de la ves&iacute;cula) por fotolitograf&iacute;a y dewetting con el control de &#39;bottom-up&#39; de caracter&iacute;sticas tama&ntilde;o nan&oacute;metro (espesor de la membrana) por molecular autoensamblado. Permite la creaci&oacute;n espont&aacute;nea de ves&iacute;culas unilaminar con una distribuci&oacute;n de tama&ntilde;o estrecha que podr&iacute;a encontrar aplicaciones en drogas y genes, nano - y micro-reactores, sustratos para Cristalograf&iacute;a macromolecular y sistemas modelo para estudios de la funci&oacute;n de la membrana.

Con plantilla formaci&oacute;n de ves&iacute;culas de pol&iacute;mero gigante con distribuciones de tama&ntilde;o controlado.

Challenges in soft nanotechnology.

Depletion of PCBM at the cathode interface in P3HT/PCBM thin films as quantified via neutron reflectivity measurements.

Here, a new procedure and method are presented for the production of highly grafted polymer brushes. Thiol-terminated polyethylene oxide (PEO-SH) of molecular weight (M(w)) 20,000 (20k) is grafted to a gold surface from highly concentrated aqueous solutions of nonthiolated polyethylene oxide homopolymer. The M(w) and volume fraction of the homopolymer solution are varied in order to control the grafting density of the resulting PEO-SH brush. As a result, 20k M(w) PEO-SH brushes with grafting densities up to 0.3 chains/nm(2) are achieved, as determined by ellipsometry. Highly concentrated homopolymer solutions of volume fraction greater than approximately 12% and M(w) greater than approximately 938 produce near-ideal solvent conditions for the 20k M(w) PEO-SH chains; we have found that this facilitates the achievement of higher grafting densities of end-functionalized polymer brushes than would be possible from simple solutions. We propose this as a suitable method for applications where the grafting density of a brush surface must be accurately varied and controlled consistently. The effect of chemisorption time and cleaning procedure on the resulting brush grafting density are also explored.

Producing high-density high-molecular-weight polymer brushes by a "grafting to" method from a concentrated homopolymer solution.

Una classe di microswimmers artificiale con combinato traslazionale e rotazionale auto-propulsione &egrave; studiata sperimentalmente. Il microswimmers chimicamente alimentato sono realizzate delle doppiette di perline colloidale Janus con patch catalitica che sono posizionate in un angolo fisso rispetto a altra. Lo spostamento quadratico medio e lo spostamento angolare-mean-square dei doublets attivo sono analizzati nel contesto di una semplice descrizione di Langevin, che utilizza le caratteristiche fisiche di microswimmers come la spontanea traslazionale e velocit&agrave; di rotazione vengono estratti. Il nostro lavoro suggerisce strategie per la progettazione di microswimmers che potrebbe seguire prescritto traiettorie cicloidali.

I corridori autonomi auto-assemblati e bicchieri.

&#x4E0E;&#x7EC4;&#x5408;&#x7684;&#x5E73;&#x79FB;&#x548C;&#x65CB;&#x8F6C;&#x81EA;&#x6211;&#x63A8;&#x8FDB;&#x7684;&#x4EBA;&#x5DE5; microswimmers &#x4E00;&#x7C7B;&#x662F;&#x5B9E;&#x9A8C;&#x6027;&#x7814;&#x7A76;&#x3002;&#x5316;&#x5B66;&#x71C3;&#x6599;&#x7684; microswimmers &#x662F;&#x7531; Janus &#x80F6;&#x4F53;&#x73E0;&#x4E0E;&#x50AC;&#x5316;&#x4FEE;&#x8865;&#x7A0B;&#x5E8F;&#x90FD;&#x653E;&#x7F6E;&#x5728;&#x4E00;&#x4E2A;&#x56FA;&#x5B9A;&#x7684;&#x89D2;&#x5EA6;&#xFF0C;&#x76F8;&#x5BF9;&#x4E8E;&#x53E6;&#x4E00;&#x4E2A;&#x7684;&#x60C5;&#x51B5;&#x3002;&#x5747;&#x65B9;&#x4F4D;&#x79FB;&#x548C;&#x5747;&#x65B9;&#x89D2;&#x4F4D;&#x79FB;&#x7684;&#x6D3B;&#x52A8;&#x7684;&#x60C5;&#x51B5;&#x7B80;&#x5355;&#x7684;&#x90CE;&#x4E4B;&#x4E07;&#x8BF4;&#x660E;&#xFF0C;&#x4F7F;&#x7528;&#x7684; microswimmers &#x7B49;&#x7684;&#x81EA;&#x53D1;&#x8F6C;&#x5316;&#x7684;&#x7269;&#x7406;&#x7279;&#x6027;&#x7684;&#x4E0A;&#x4E0B;&#x6587;&#x4E2D;&#x8FDB;&#x884C;&#x5206;&#x6790;&#x548C;&#x63D0;&#x53D6;&#x7684;&#x65CB;&#x8F6C;&#x901F;&#x5EA6;&#x3002;&#x6211;&#x4EEC;&#x7684;&#x5DE5;&#x4F5C;&#x8868;&#x660E;&#x8BBE;&#x8BA1; microswimmers&#xFF0C;&#x53EF;&#x4EE5;&#x6309;&#x7167;&#x8BE5;&#x7B56;&#x7565;&#x6240;&#x8BA2;&#x660E;&#x6446;&#x7684;&#x8F68;&#x8FF9;&#x3002;

&#x81EA;&#x7EC4;&#x88C5;&#x81EA;&#x4E3B;&#x8D5B;&#x8DD1;&#x548C;&#x9152;&#x676F;&#x3002;

A class of artificial microswimmers with combined translational and rotational self-propulsion is studied experimentally. The chemically fueled microswimmers are made of doublets of Janus colloidal beads with catalytic patches that are positioned at a fixed angle relative to one another. The mean-square displacement and the mean-square angular displacement of the active doublets are analyzed in the context of a simple Langevin description, using which the physical characteristics of the microswimmers such as the spontaneous translational and rotational velocities are extracted. Our work suggests strategies for designing microswimmers that could follow prescribed cycloidal trajectories.

Self-assembled autonomous runners and tumblers.

Une classe de microswimmers artificielle avec combin&eacute; translation et de rotation autopropulsion on &eacute;tudie exp&eacute;rimentalement. Les microswimmers chimiquement aliment&eacute;s sont faits des doublets de perles collo&iuml;dales de Janus avec correctifs catalytiques qui doivent &ecirc;tre plac&eacute;s &agrave; un angle fixe par rapport &agrave; l&#39;autre. Le d&eacute;placement quadratique moyenne et le d&eacute;placement angulaire moyenne quadratique de l&#39;actifs doublets sont analys&eacute;s dans le cadre d&#39;une simple description de Langevin, qui aide les caract&eacute;ristiques physiques de la microswimmers comme le spontan&eacute; translationnelle et vitesses de rotationnels sont extraits. Notre travail sugg&egrave;re de strat&eacute;gies pour la conception de microswimmers pouvant suivre prescrit cyclo&iuml;dales trajectoires.

Les coureurs autonomes auto-assembl&eacute;s et gobelets.

Eine Klasse von k&uuml;nstlichen Microswimmers mit kombinierten translatorischen und rotatorischen--einschlie&szlig;lich wird experimentell untersucht. Die chemisch heizten Microswimmers bestehen aus Dubletten von Janus kolloidale Perlen mit katalytischen Patches, die in einem festen Winkel zueinander positioniert sind. Die mittlere quadratische Verschiebung und die quadratisch gemittelte Winkelversatz von der aktiven Doubletten werden im Zusammenhang mit einer einfache Langevin-Beschreibung, durch die die physikalischen Eigenschaften von den Microswimmers wie dem spontanen translational analysiert und Rotations-Geschwindigkeiten werden extrahiert. Unsere Arbeit legt nahe, dass Strategien f&uuml;r das Entwerfen von Microswimmers, die Folgen k&ouml;nnten Zykloide Bahnen vorgeschrieben.

Monomolekularen autonome L&auml;ufer und Trinkgl&auml;ser.

&#x7D50;&#x5408;&#x306E;&#x56DE;&#x8EE2;&#x304A;&#x3088;&#x3073;&#x4E26;&#x9032;&#x904B;&#x52D5;&#x81EA;&#x8D70;&#x3067;&#x4EBA;&#x5DE5; microswimmers &#x306E;&#x30AF;&#x30E9;&#x30B9;&#x3092;&#x5B9F;&#x9A13;&#x691C;&#x8A3C;&#x3057;&#x307E;&#x3057;&#x305F;&#x3002;&#x5316;&#x5B66;&#x7684;&#x306B;&#x71C3;&#x6599;&#x306E; microswimmers &#x306F;&#x3001;&#x30E4;&#x30CC;&#x30B9; &#x30B3;&#x30ED;&#x30A4;&#x30C9; &#x30D3;&#x30FC;&#x30BA;&#x306B;&#x56FA;&#x5B9A;&#x89D2;&#x5EA6;&#x304C;&#x4E92;&#x3044;&#x306B;&#x76F8;&#x5BFE;&#x7684;&#x306B;&#x914D;&#x7F6E;&#x3055;&#x308C;&#x305F;&#x89E6;&#x5A92;&#x306E;&#x30D1;&#x30C3;&#x30C1;&#x306E;&#x30C0;&#x30D6;&#x30EC;&#x30C3;&#x30C8;&#x306E;&#x4F5C;&#x3089;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x5E73;&#x5747; 2&#x4E57;&#x5909;&#x4F4D;&#x3068;&#x30A2;&#x30AF;&#x30C6;&#x30A3;&#x30D6;&#x306A;&#x30C0;&#x30D6;&#x30EC;&#x30C3;&#x30C8;&#x306E;&#x5E73;&#x5747;&#x4E8C;&#x4E57;&#x89D2;&#x5EA6;&#x5909;&#x4F4D;&#x306E;&#x4E26;&#x9032;&#x306E; microswimmers &#x306A;&#x3069;&#x3001;&#x81EA;&#x7136;&#x306E;&#x7269;&#x7406;&#x7684;&#x7279;&#x6027;&#x3092;&#x4F7F;&#x7528;&#x3057;&#x3066;&#x5358;&#x7D14;&#x306A;&#x30E9;&#x30F3;&#x30B8;&#x30E5;&#x30D0;&#x30F3;&#x306E;&#x8AAC;&#x660E;&#x306F;&#x3001;&#x30B3;&#x30F3;&#x30C6;&#x30AD;&#x30B9;&#x30C8;&#x3067;&#x5206;&#x6790;&#x3055;&#x308C;&#x3001;&#x56DE;&#x8EE2;&#x901F;&#x5EA6;&#x304C;&#x62BD;&#x51FA;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002;&#x79C1;&#x305F;&#x3061;&#x306E;&#x4ED5;&#x4E8B;&#x306F;&#x3001;&#x30B5;&#x30A4;&#x30AF;&#x30ED;&#x30A4;&#x30C9;&#x8ECC;&#x9053;&#x306B;&#x5F93;&#x3046;&#x3053;&#x3068;&#x304C;&#x3067;&#x304D;&#x308B; microswimmers &#x306E;&#x8A2D;&#x8A08;&#x6226;&#x7565;&#x3092;&#x898F;&#x5B9A;&#x3059;&#x308B;&#x793A;&#x5506;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;

&#x81EA;&#x5DF1;&#x7D44;&#x7E54;&#x5316;&#x81EA;&#x5F8B;&#x30E9;&#x30F3;&#x30CA;&#x30FC;&#x3068;&#x30BF;&#x30F3;&#x30D6;&#x30E9;&#x30FC;&#x3002;

&#xACB0;&#xD569; &#xB41C; &#xBCC0;&#xD658; &#xBC0F; &#xD68C;&#xC804; &#xC790;&#xCCB4; &#xCD94;&#xC9C4;&#xC73C;&#xB85C; &#xC778;&#xACF5; microswimmers &#xD074;&#xB798;&#xC2A4;&#xB294; &#xC2E4;&#xD5D8;&#xC801;&#xC73C;&#xB85C; &#xACF5;&#xBD80; &#xD558; &#xACE0; &#xC788;&#xB2E4;. &#xD654;&#xD559;&#xC801;&#xC73C;&#xB85C; &#xC5F0;&#xB8CC; microswimmers &#xC11C;&#xB85C; &#xACE0;&#xC815;&#xB41C; &#xAC01;&#xB3C4; &#xC704;&#xCE58;&#xB97C; &#xC9C0;&#xC815; &#xD558;&#xB294; &#xCD09;&#xB9E4; &#xD328;&#xCE58;&#xB85C; &#xC57C;&#xB204;&#xC2A4; &#xCF5C; &#xB85C;&#xC774;&#xB4DC; &#xAD6C;&#xC2AC;&#xC758; &#xB0A8;&#xC790;&#xC758; &#xB9CC;&#xB4E4;&#xC5B4;&#xC9D1;&#xB2C8;&#xB2E4;. &#xC758;&#xBBF8;-&#xC2A4;&#xD018;&#xC5B4; &#xBCC0;&#xC704; &#xBC0F; &#xD65C;&#xC131; &#xB0A8;&#xC790;&#xC758; &#xC758;&#xBBF8;-&#xC2A4;&#xD018;&#xC5B4; &#xAC01;&#xB3C4; &#xBCC0;&#xC704;&#xB97C; &#xBCC0;&#xD658;&#xB294; &#xC790;&#xBC1C;&#xC801;&#xC778; &#xAC19;&#xC740; microswimmers&#xC758; &#xBB3C;&#xB9AC;&#xC801; &#xD2B9;&#xC131;&#xC744; &#xC0AC;&#xC6A9; &#xD558; &#xC5EC; &#xAC04;&#xB2E8;&#xD55C; Langevin &#xC124;&#xBA85;&#xC758; &#xB9E5;&#xB77D;&#xC5D0;&#xC11C; &#xBD84;&#xC11D; &#xD558; &#xACE0; &#xD68C;&#xC804; &#xC18D;&#xB3C4; &#xCD94;&#xCD9C;. &#xC6B0;&#xB9AC;&#xC758; &#xC77C; &#xC218;&#xC5D0; &#xB530;&#xB77C; microswimmers &#xC124;&#xACC4;&#xB97C; &#xC704;&#xD55C; &#xC804;&#xB7B5; &#xCC98;&#xBC29; &#xC0AC;&#xC774;&#xD074;&#xB85C;&#xC774;&#xB4DC; &#xADA4;&#xC801;&#xC744; &#xC81C;&#xC548; &#xD569;&#xB2C8;&#xB2E4;.

&#xC870;&#xB9BD;&#xB41C; &#xC790;&#xCE58; &#xC8FC;&#xC790;&#xC640; &#xD68C;&#xC804;&#xD310;&#xC785;&#xB2C8;&#xB2E4;.

Una clase de microswimmers artificial con combinado traslacional y rotacional automoci&oacute;n es estudiada experimentalmente. Los microswimmers qu&iacute;micamente alimentadas est&aacute;n constituidos por dobletes de granos coloidales Janus con parches catal&iacute;ticos que se colocan en un &aacute;ngulo fijo en relaci&oacute;n a uno con el otro. Velocidades de rotaci&oacute;n se extraen y se analizaron el desplazamiento cuadr&aacute;tico medio y el desplazamiento angular cuadrada media de los dobletes activos en el contexto de una simple descripci&oacute;n de Langevin, que utiliza las caracter&iacute;sticas f&iacute;sicas de la microswimmers como la espont&aacute;nea traslacional. Nuestro trabajo sugiere estrategias para el dise&ntilde;o de microswimmers que podr&iacute;a seguir prescriben cycloidal trayectorias.

Corredores aut&oacute;nomos autoensamblados y vasos.

We have investigated a novel method of remotely switching the conformation of a weak polybase brush using an applied voltage. Surface-grafted polyelectrolyte brushes exhibit rich responsive behavior and show great promise as "smart surfaces", but existing switching methods involve physically or chemically changing the solution in contact with the brush. In this study, high grafting density poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) brushes were grown from silicon surfaces using atom transfer radical polymerization. Optical ellipsometry and neutron reflectivity were used to measure changes in the profiles of the brushes in response to DC voltages applied between the brush substrate and a parallel electrode some distance away in the surrounding liquid (water or D(2)O). Positive voltages were shown to cause swelling, while negative voltages in some cases caused deswelling. Neutron reflectometry experiments were carried out on the INTER reflectometer (ISIS, Rutherford Appleton Laboratory, UK) allowing time-resolved measurements of polymer brush structure. The PDMAEMA brushes were shown to have a polymer volume fraction profile described by a Gaussian-terminated parabola both in the equilibrium and in the partially swollen states. At very high positive voltages (in this study, positive bias means positive voltage to the brush-bearing substrate), the brush chains were shown to be stretched to an extent comparable to their contour length, before being physically removed from the interface. Voltage-induced swelling was shown to exhibit a wider range of brush swelling states in comparison to pH switching, with the additional advantages that the stimulus is remotely controlled and may be fully automated.

Voltage-induced swelling and deswelling of weak polybase brushes.

We report surface and interface effects in dynamics and chain conformation in the thin film of conjugated polymer PCDTBT. To probe dynamic anomalies, we measure the glass transition temperature (T(g)) of PCDTBT films as a function of thickness, and find that there is a significant depression in T(g) for films less than 100 nm thick; a result qualitatively similar to that observed in many other polymer film systems. However, for films less than 40 nm, the T(g) converges to a constant value of 20 K below its bulk value. Grazing incidence X-ray diffraction shows depth-dependent molecular organization that is associated with the unusual thickness-dependent dynamics.

Competition between substrate-mediated π-π stacking and surface-mediated T(g) depression in ultrathin conjugated polymer films.

The adsorption of lysozyme protein was measured ex situ on well-characterized gold surfaces coated by end-tethered polyethylene oxide brushes of various molecular weights and controlled grafting densities. The adsorbed amount of protein for different molecular weight brushes was found to collapse onto one master curve when plotted against brush coverage. We interpret this relationship in terms of a model involving site-blocking of the adsorption of proteins at the substrate and discuss the role of the physical attraction of PEO segments to gold. We account for our observation of a simple exponential relationship between protein adsorption and normalized brush coverage with a simple protein adsorption model. In contrast to other studies in similar systems, we do not observe protein adsorption on brushes at high grafting density, and we suggest that this discrepancy may be due to the solubility effects of salt upon the brushes, influencing their protein binding affinity, in the limit of high grafting density and high brush volume fraction.

Article	Year
Correlating structure with fluorescence emission in phase-separated conjugated-polymer blends. Nature materials\| PubMed ID: 12923529	2003
Amorphous materials: Glasses with liquid-like surfaces. Nature materials\| PubMed ID: 14520342	2003
Tough and smart. Nature materials\| PubMed ID: 15085859	2004
Chain entanglement in thin freestanding polymer films. Physical review letters\| PubMed ID: 15903962	2005
An interfacial instability in a transient wetting layer leads to lateral phase separation in thin spin-cast polymer-blend films. Nature materials\| PubMed ID: 16142241	2005
Reciprocating power generation in a chemically driven synthetic muscle. Nano letters\| PubMed ID: 16402790	2006
Self-motile colloidal particles: from directed propulsion to random walk. Physical review letters\| PubMed ID: 17678409	2007
Floating lipid bilayers deposited on chemically grafted phosphatidylcholine surfaces. Langmuir : the ACS journal of surfaces and colloids\| PubMed ID: 18198904	2008
Templated formation of giant polymer vesicles with controlled size distributions. Nature materials\| PubMed ID: 19448615	2009
Challenges in soft nanotechnology. Faraday discussions\| PubMed ID: 20334091	2009
Depletion of PCBM at the cathode interface in P3HT/PCBM thin films as quantified via neutron reflectivity measurements. Advanced materials (Deerfield Beach, Fla.)\| PubMed ID: 20491090	2010
Producing high-density high-molecular-weight polymer brushes by a "grafting to" method from a concentrated homopolymer solution. Langmuir : the ACS journal of surfaces and colloids\| PubMed ID: 20672847	2010
Self-assembled autonomous runners and tumblers. Physical review. E, Statistical, nonlinear, and soft matter physics\| PubMed ID: 20866681	2010
Voltage-induced swelling and deswelling of weak polybase brushes. Langmuir : the ACS journal of surfaces and colloids\| PubMed ID: 21793596	2011
Competition between substrate-mediated π-π stacking and surface-mediated T(g) depression in ultrathin conjugated polymer films. The European physical journal. E, Soft matter\| PubMed ID: 23239269	2012
Protein adsorption on well-characterized polyethylene oxide brushes on gold: dependence on molecular weight and grafting density. Langmuir : the ACS journal of surfaces and colloids\| PubMed ID: 23617308	2013

Richard A. L. Jones

Biography

JoVE Journal Publications

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