نحن نعترف بامتنان المؤسسة الوطنية للعلوم (CHE - 0847145) ، وهنري دريفوس برنامج جوائز مدرس باحث بسخاء لدعم هذه البحوث. نود أن يتعرف على وجه التحديد كريستين ديفيس ، مدير الميكروسكوب والتصوير في قسم البيولوجيا في جامعة ريتشموند لتقديم المساعدة لها مستعرضة التصوير. ويرد شكر خاص الى الدكاترة. T. ليوبولد ، R. Kanters ، كيلوغ D. ، R. ميلر ، وجورج القضية ، وكذلك ، روس كولينز ، جوزيف فيل ، كارولين ماركس ، ومالوري ماندي Wimbush جون -- كل منهم جعل البحوث الجامعية في جامعة ممكن من ريتشموند. ويرد شخصي جدا شكرا لجميع الباحثين الحالي الجامعية الماضية ، والمستقبل في مختبر بحوث ليوبولد.

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W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monolayer-Protected+Cluster+Molecules.">Monolayer-Protected Cluster Molecules.</a> Accounts. Chem. Res. 33, 27-36 (2000).</li><li>Aguila, A., Murray, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monolayer-Protected+Clusters+with+Fluorescent+Dansyl+Ligands.">Monolayer-Protected Clusters with Fluorescent Dansyl Ligands.</a> Langmuir. 16, 5949-5954 (2000).</li><li>Hostetler, M. J., Templeton, A. C., Murray, R. 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الإعلان عن أي تضارب في المصالح.

البروتين أحادي الطبقة الكهربائية هي تقنية فعالة تستخدم لدراسة التفاعلات بين البروتينات ومنصات إمتزاز الأكسدة الاصطناعية. فعالية هذه الاستراتيجية ، ومع ذلك ، يعتمد على القدرة على الامتصاص واجهة مهندس على درجة عالية من السيطرة المستوى الجزيئي. المنصات القائمة على إ?...

<table border="1" style=";text-align:right;direction:rtl"><tr><th> اسم كاشف والمعدات </th><th> شركة </th><th> فهرس العدد </th></tr><tr><td> Tetraoctylammonium بروميد </td><td> سيغما الدريخ </td><td> 294136 </td></tr><tr><td> بوروهيدريد الصوديوم </td><td> سيغما الدريخ </td><td> 213462 </td></tr><tr><td> الهيدروجين tetrachloroaurate </td><td> سيغما الدريخ </td><td> 254169 - 5G </td></tr><tr><td> 1 - Hexanethiol </td><td> سيغما الدريخ </td><td> 234192 </td></tr><tr><td> انتقال الكترون المجهر </td><td> JEOL </td><td> 1010 </td></tr><tr><td> مطياف الرنين المغناطيسي النووي </td><td> سميت بال بروكر </td><td> 300 ميغاهيرتز </td></tr><tr><td> Formvar / الكربون الفيلم على دعم الشبكة النحاسية (400 شبكة) </td><td> الإلكترون المجهري العلوم </td><td> FCF400 النحاس </td></tr><tr><td> الذهب الركيزة </td><td> تبخرت أفلام شركة معادن </td><td> عرف </td></tr><tr><td> جي / AgCl المرجعي الكهربائي </td><td> Microelectrodes ، وشركة </td><td> MI - 401F </td></tr><tr><td> Potentiostats </td><td> CH الآلات ، وشركة </td><td> CHI650A ، CHI610B </td></tr><tr><td> 1،9 - Nonanedithiol </td><td> سيغما الدريخ </td><td> N29805 </td></tr><tr><td> (3 - mercaptopropyl) - trimethoxysilane </td><td> سيغما الدريخ </td><td> 175617 </td></tr><tr><td> الطيف المرئي الأشعة فوق البنفسجية </td><td> اجيلنت </td><td> 8453 </td></tr><tr><td> تضمين راتنجات الايبوكسي 812 </td><td> الإلكترون المجهري العلوم </td><td> 14120 </td></tr><tr><td> &quot;00&quot; كبسولة BEEM </td><td> الإلكترون المجهري العلوم </td><td> 70000 - B </td></tr><tr><td> السيليكون قالب مسطح </td><td> الإلكترون المجهري العلوم </td><td> 70900 </td></tr><tr><td> الماس سكين </td><td> Diatome </td><td> 21 - الندبة ، S12801 </td></tr></table>

synthesis, assembly, and characterization of monolayer protected gold nanoparticle films for protein monolayer electrochemistry

الذهب النانوية الغروية المحمية مع يغاندس alkanethiolate دعت مجموعات أحادي الطبقة الذهب المحمية (البلدان المتوسطية الشريكة) تم تجميعها ودمجها لاحقا في فيلم الجمعيات التي تكون بمثابة منصات لامتصاص البروتين أحادي الطبقة الكهربائية (PME). كما يستخدم PME في النظام النموذجي لدراسة خصائص الكهروكيميائية من البروتينات الأكسدة التي حصرها لمنصة الامتزاز في القطب المعدل ، الذي يشغل أيضا منصب شريك لتفاعلات الأكسدة الإلكترون (ET) نقل. وقد أظهرت الدراسات أن الذهب الجمعيات جسيمات متناهية الصغر فيلم من هذا النوع توفر بيئة البروتين الامتزاز أكثر تجانسا وتعزيز ET دون الاعتماد على المسافة بالمقارنة مع الأنظمة التقليدية مع تعديل monolayers الذاتي تجميعها alkanethiol (SAM). 1-3 في هذه الورقة ، البلدان المتوسطية الشريكة functionalized مع يغاندس hexanethiolate تم تجميعها باستخدام تفاعل Brust تعديل (4) ويتميز التحليل الطيفي فوق البنفسجية المرئية (UV - VIS) ، ونقل الإلكترون المجهري (TEM) والبروتون (1 H) الرنين المغناطيسي النووي (NMR). ويتم تجميع الأفلام MPC على تعديل واجهات SAM القطب الذهب باستخدام &quot;دورة الانخفاض&quot; طريقة بالتناوب طبقات لجنة السياسة النقدية وربط جزيئات ثنائي الثيول. يتم تعقب النمو الفيلم في القطب الذهب electrochemically من خلال قياس التغييرات في طبقة مزدوجة الشحن الحالية للنظام. أفلام مشابهة تجميعها على الشرائح الزجاجية سيلاني تعديل يسمح للمراقبة البصرية للنمو السينما ومستعرضة تحليل تيم يوفر سماكة الفيلم المقدرة. خلال تجميع الفيلم ، والتلاعب في حماية يجند MPC فضلا عن الربط بين الجسيمات آلية تسمح للأفلام الشبكية ، التي هي قابلة للتكيف بسهولة ، إلى واجهة مع وجود بروتين الأكسدة المختلفة الامتزاز الآلية. على سبيل المثال ، يمكن كثف الزائفة الزنجارية azurin (AZ) hydrophobically لثنائي الثيول المرتبطة الأفلام من البلدان المتوسطية الشريكة وhexanethiolate السيتوكروم ج (cyt ج) يمكن أن يجمد كهربية في حمض الكربوكسيلية تعديل MPC طبقة بينية. في هذا التقرير ، ونحن نركز على بروتوكول فيلم للنظام من الالف الى الياء حصرا. يمكن أن التحقيقات التي تنطوي على امتصاص البروتينات على منصات تعديل MPC الاصطناعية زيادة فهم التفاعلات بين الجزيئات الحيوية ومواد من صنع الإنسان ، وبالتالي المساعدة على تطوير خطط جهاز الاستشعار البيولوجي ، ونظم النمذجة ET ، والمواد الاصطناعية حيويا. 5-8

Watch this Scientific Journal Video about Synthesis, Assembly, and Characterization of Monolayer Protected Gold Nanoparticle Films for Protein Monolayer Electrochemistry at JoVE.com

Synthesis, Assembly, and Characterization of Monolayer Protected Gold Nanoparticle Films for Protein Monolayer Electrochemistry

وقد تم تجميع الغرويات Alkanethiolate الذهب استقرت مجموعات أحادي الطبقة المعروفة باسم المحمية (البلدان المتوسطية الشريكة) ، وتتميز ، وتجميعها في الأغشية الرقيقة بمثابة واجهة لامتصاص البروتين أحادي الطبقة الكهربائية من البروتين الأكسدة بسيطة مثل<em&gt; الزائفة الزنجارية</em&gt; azurin (AZ) والسيتوكروم<em&gt; ج</em&gt; (cyt<em&gt; ج</em&gt;).

التوليف ، والجمعية ، وتوصيف أحادي الطبقة المحمية الجسيمات النانوية الذهبية للأفلام كهربية البروتين أحادي الطبقة

Colloidal gold nanoparticles protected with alkanethiolate ligands called monolayer protected gold clusters (MPCs) are synthesized and subsequently ...

synthesis-assembly-characterization-monolayer-protected-gold

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Bioengineering

14.4K Views.  University of Richmond. وقد تم تجميع الغرويات Alkanethiolate الذهب استقرت مجموعات أحادي الطبقة المعروفة باسم المحمية (البلدان المتوسطية الشريكة) ، وتتميز ، وتجميعها في الأغشية الرقيقة بمثابة واجهة لامتصاص البروتين أحادي الطبقة الكهربائية من البروتين الأكسدة بسيطة مثل الزائفة الزنجاري?...

Video: Synthesis, Assembly, and Characterization of Monolayer Protected Gold Nanoparticle Films for Protein Monolayer Electrochemistry

Gold Nanostar Synthesis with a Silver Seed Mediated Growth Method

The physical, chemical and optical properties of nano-scale colloids depend on their material composition, size and shape 1-5. There is a great interest in using nano-colloids for photo-thermal ablation, drug delivery and many other biomedical applications 6. Gold is particularly used because of its low toxicity 7-9. A property of metal nano-colloids is that they can have a strong surface plasmon resonance 10. The peak of the surface plasmon resonance mode depends on the structure and composition of the metal nano-colloids. Since the surface plasmon resonance mode is stimulated with light there is a need to have the peak absorbance in the near infrared where biological tissue transmissivity is maximal 11, 12.
We present a method to synthesize star shaped colloidal gold, also known as star shaped nanoparticles 13-15 or nanostars 16. This method is based on a solution containing silver seeds that are used as the nucleating agent for anisotropic growth of gold colloids 17-22. Scanning electron microscopy (SEM) analysis of the resulting gold colloid showed that 70 % of the nanostructures were nanostars. The other 30 % of the particles were amorphous clusters of decahedra and rhomboids. The absorbance peak of the nanostars was detected to be in the near infrared (840 nm). Thus, our method produces gold nanostars suitable for biomedical applications, particularly for photo-thermal ablation.

We synthesized star shaped gold nanostars using a silver seed mediated growth method. The diameter of the nanostars ranges from 200 to 300 nm and the number of tips vary from 7 to 10. The nanoparticles have a broad surface plasmon resonance mode centered in the near infrared.

الذهب Nanostar التجميعي مع أسلوب بذور فضة النمو وساطة

The physical, chemical and optical properties of nano-scale colloids depend on their material composition, size and shape 1-5. There is a great interest ...

Low Molecular Weight Protein Enrichment on Mesoporous Silica Thin Films for Biomarker Discovery

The identification of circulating biomarkers holds great potential for non invasive approaches in early diagnosis and prognosis, as well as for the monitoring of therapeutic efficiency.1-3 The circulating low molecular weight proteome (LMWP) composed of small proteins shed from tissues and cells or peptide fragments derived from the proteolytic degradation of larger proteins, has been associated with the pathological condition in patients and likely reflects the state of disease.4,5 Despite these potential clinical applications, the use of Mass Spectrometry (MS) to profile the LMWP from biological fluids has proven to be very challenging due to the large dynamic range of protein and peptide concentrations in serum.6 Without sample pre-treatment, some of the more highly abundant proteins obscure the detection of low-abundance species in serum/plasma. Current proteomic-based approaches, such as two-dimensional polyacrylamide gel-electrophoresis (2D-PAGE) and shotgun proteomics methods are labor-intensive, low throughput and offer limited suitability for clinical applications.7-9 Therefore, a more effective strategy is needed to isolate LMWP from blood and allow the high throughput screening of clinical samples. 
Here, we present a fast, efficient and reliable multi-fractionation system based on mesoporous silica chips to specifically target and enrich LMWP.10,11 Mesoporous silica (MPS) thin films with tunable features at the nanoscale were fabricated using the triblock copolymer template pathway. Using different polymer templates and polymer concentrations in the precursor solution, various pore size distributions, pore structures, connectivity and surface properties were determined and applied for selective recovery of low mass proteins. The selective parsing of the enriched peptides into different subclasses according to their physicochemical properties will enhance the efficiency of recovery and detection of low abundance species. In combination with mass spectrometry and statistic analysis, we demonstrated the correlation between the nanophase characteristics of the mesoporous silica thin films and the specificity and efficacy of low mass proteome harvesting. The results presented herein reveal the potential of the nanotechnology-based technology to provide a powerful alternative to conventional methods for LMWP harvesting from complex biological fluids. Because of the ability to tune the material properties, the capability for low-cost production, the simplicity and rapidity of sample collection, and the greatly reduced sample requirements for analysis, this novel nanotechnology will substantially impact the field of proteomic biomarker research and clinical proteomic assessment.

We developed a technology based on mesoporous silica thin film for the selective recovery of low molecular weight proteins and peptides from human serum. The physico-chemical properties of our mesoporous chips were finely tuned to provide substantial control in peptide enrichment and consequently profile the serum proteome for diagnostic purposes.

بروتين منخفض الوزن الجزيئي تخصيب اليورانيوم على أفلام السيليكا Mesoporous رقيقة لاكتشاف العلامات البيولوجية

The identification of circulating biomarkers holds great potential for non invasive approaches in early diagnosis and prognosis, as well as for the ...

Combinatorial Synthesis of and High-throughput Protein Release from Polymer Film and Nanoparticle Libraries

Polyanhydrides are a class of biomaterials with excellent biocompatibility and drug delivery capabilities. While they have been studied extensively with conventional one-sample-at-a-time synthesis techniques, a more recent high-throughput approach has been developed enabling the synthesis and testing of large libraries of polyanhydrides1. This will facilitate more efficient optimization and design process of these biomaterials for drug and vaccine delivery applications. The method in this work describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries. In this robotically operated method (Figure 1), linear actuators and syringe pumps are controlled by LabVIEW, which enables a hands-free automated protocol, eliminating user error. Furthermore, this method enables the rapid fabrication of micro-scale polymer libraries, reducing the batch size while resulting in the creation of multivariant polymer systems. This combinatorial approach to polymer synthesis facilitates the synthesis of up to 15 different polymers in an equivalent amount of time it would take to synthesize one polymer conventionally. In addition, the combinatorial polymer library can be fabricated into blank or protein-loaded geometries including films or nanoparticles upon dissolution of the polymer library in a solvent and precipitation into a non-solvent (for nanoparticles) or by vacuum drying (for films). Upon loading a fluorochrome-conjugated protein into the polymer libraries, protein release kinetics can be assessed at high-throughput using a fluorescence-based detection method (Figures 2 and 3) as described previously1. This combinatorial platform has been validated with conventional methods2 and the polyanhydride film and nanoparticle libraries have been characterized with 1H NMR and FTIR. The libraries have been screened for protein release kinetics, stability and antigenicity; in vitro cellular toxicity, cytokine production, surface marker expression, adhesion, proliferation and differentiation; and in vivo biodistribution and mucoadhesion1-11. The combinatorial method developed herein enables high-throughput polymer synthesis and fabrication of protein-loaded nanoparticle and film libraries, which can, in turn, be screened in vitro and in vivo for optimization of biomaterial performance.

This method describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries.

اندماجي تجميع وعالية الإنتاجية الإصدار البروتين من فيلم البوليمر ومكتبات جسيمات متناهية الصغر

Polyanhydrides are a class of biomaterials with excellent biocompatibility and drug delivery capabilities. While they have been studied extensively with ...

Synthesis of an Intein-mediated Artificial Protein Hydrogel

We present the synthesis of a highly stable protein hydrogel mediated by a split-intein-catalyzed protein trans-splicing reaction. The building blocks of this hydrogel are two protein block-copolymers each containing a subunit of a trimeric protein that serves as a crosslinker and one half of a split intein. A highly hydrophilic random coil is inserted into one of the block-copolymers for water retention. Mixing of the two protein block copolymers triggers an intein trans-splicing reaction, yielding a polypeptide unit with crosslinkers at either end that rapidly self-assembles into a hydrogel. This hydrogel is very stable under both acidic and basic conditions, at temperatures up to 50 &#176;C, and in organic solvents. The hydrogel rapidly reforms after shear-induced rupture. Incorporation of a &#34;docking station peptide&#34; into the hydrogel building block enables convenient incorporation of &#34;docking protein&#34;-tagged target proteins. The hydrogel is compatible with tissue culture growth media, supports the diffusion of 20 kDa molecules, and enables the immobilization of bioactive globular proteins. The application of the intein-mediated protein hydrogel as an organic-solvent-compatible biocatalyst was demonstrated by encapsulating the horseradish peroxidase enzyme and corroborating its activity.

We present the synthesis of a split-intein-mediated protein hydrogel. The building blocks of this hydrogel are two protein copolymers each containing a subunit of a trimeric protein that serves as a crosslinker and one half of a split intein. Mixing of the two protein copolymers triggers an intein trans-splicing reaction, yielding a polypeptide unit that self-assembles into a hydrogel. This hydrogel is highly pH- and temperature-stable, compatible with organic solvents, and easily incorporates functional globular proteins.

التوليف من البروتين الاصطناعي Intein بوساطة هيدروجيل

We present the synthesis of a highly stable protein hydrogel mediated by a split-intein-catalyzed protein trans-splicing reaction. The building blocks of ...

Fluorescence Recovery after Merging a Droplet to Measure the Two-dimensional Diffusion of a Phospholipid Monolayer

We introduce a new method to measure the lateral diffusivity of a surfactant monolayer at the fluid-fluid interface, called fluorescence recovery after merging (FRAM). FRAM adopts the same principles as the fluorescence recovery after photobleaching (FRAP) technique, especially for measuring fluorescence recovery after bleaching a specific area, but FRAM uses a drop coalescence instead of photobleaching dye molecules to induce a chemical potential gradient of dye molecules. Our technique has several advantages over FRAP: it only requires a fluorescence microscope rather than a confocal microscope equipped with high power lasers; it is essentially free from the selection of fluorescence dyes; and it has far more freedom to define the measured diffusion area. Furthermore, FRAM potentially provides a route for studying the mixing or inter-diffusion of two different surfactants, when the monolayers at a surface of droplet and at a flat air/water interface are prepared with different species, independently.

We present a new technique to measure the lateral diffusion of a surface active species at the fluid-fluid interface by merging a droplet monolayer onto a flat monolayer.

مضان الانتعاش بعد دمج قطرات لقياس انتشار ثنائي الأبعاد من الفوسفوليبيدية واحد رقائق

We introduce a new method to measure the lateral diffusivity of a surfactant monolayer at the fluid-fluid interface, called fluorescence recovery after ...

Synthesis of Gold Nanoparticle Integrated Photo-responsive Liposomes and Measurement of Their Microbubble Cavitation upon Pulse Laser Excitation

Photo-responsive nanoparticles (NPs) have received considerable attention because of their potential in providing spatial, temporal, and dosage control over the drug release. However, most of the relevant technologies are still in the development process and are unprocurable by clinics. Here, we describe a facile fabrication of these photo-responsive NPs with commercially available gold NPs and thermo-responsive liposomes. Calcein is used as a model drug to evaluate the encapsulation efficiency and the release kinetic profile upon heat/light stimulation. Finally, we show that this photo-triggered release is due to the membrane disruption caused by microbubble cavitation, which can be measured with hydrophone.

This protocol describes a simple preparation method for gold nanoparticle integrated photo-responsive liposomes with the commercially available materials. It also shows how to measure the microbubble cavitation process of the synthesized liposomes upon the treatment of pulsed laser.

توليف الذهب الجسيمات النانوية الليبوزومات المتكاملة صور متجاوبة وقياس تلك Microbubble التجويف على نبض الليزر الإثارة

Photo-responsive nanoparticles (NPs) have received considerable attention because of their potential in providing spatial, temporal, and dosage control ...

Micropatterning and Assembly of 3D Microvessels

In vitro platforms to study endothelial cells and vascular biology are largely limited to 2D endothelial cell culture, flow chambers with polymer or glass based substrates, and hydrogel-based tube formation assays. These assays, while informative, do not recapitulate lumen geometry, proper extracellular matrix, and multi-cellular proximity, which play key roles in modulating vascular function. This manuscript describes an injection molding method to generate engineered vessels with diameters on the order of 100 &#181;m. Microvessels are fabricated by seeding endothelial cells in a microfluidic channel embedded within a native type I collagen hydrogel. By incorporating parenchymal cells within the collagen matrix prior to channel formation, specific tissue microenvironments can be modeled and studied. Additional modulations of hydrodynamic properties and media composition allow for control of complex vascular function within the desired microenvironment. This platform allows for the study of perivascular cell recruitment, blood-endothelium interactions, flow response, and tissue-microvascular interactions. Engineered microvessels offer the ability to isolate the influence from individual components of a vascular niche and precisely control its chemical, mechanical, and biological properties to study vascular biology in both health and disease.

This manuscript presents an injection molding method to engineer microvessels that recapitulate physiological properties of endothelium. The microfluidic-based process creates patent 3D vascular networks with tailorable conditions, such as flow, cellular composition, geometry, and biochemical gradients. The fabrication process and examples of potential applications are described.

Micropatterning وجمعية Microvessels 3D

In vitro platforms to study endothelial cells and vascular biology are largely limited to 2D endothelial cell culture, flow chambers with polymer or glass ...

Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells

Many important biomedical applications, such as cell imaging and remote manipulation, can be achieved by labeling cells with superparamagnetic iron oxide nanoparticles (SPIONs). Achieving sufficient cellular uptake of SPIONs is a challenge that has traditionally been met by exposing cells to elevated concentrations of SPIONs or by prolonging exposure times (up to 72 hr). However, these strategies are likely to mediate toxicity. Here, we present the synthesis of the protein-based SPION magnetoferritin as well as a facile surface functionalization protocol that enables rapid cell magnetization using low exposure concentrations. The SPION core of magnetoferritin consists of cobalt-doped iron oxide with an average particle diameter of 8.2 nm mineralized inside the cavity of horse spleen apo-ferritin. Chemical cationization of magnetoferritin produced a novel, highly membrane-active SPION that magnetized human mesenchymal stem cells (hMSCs) using incubation times as short as one minute and iron concentrations as lows as 0.2 mM.

A protocol for the synthesis and cationization of cobalt-doped magnetoferritin is presented, as well as a method to rapidly magnetize stem cells with cationized magnetoferritin.

توليف Cationized Magnetoferritin للمغنطة فائقة السرعة من الخلايا

Many important biomedical applications, such as cell imaging and remote manipulation, can be achieved by labeling cells with superparamagnetic iron oxide ...

Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery

Gold nanoparticles (AuNPs) have been used extensively in medical research due to their size, biocompatibility, and modifiable surface. Specific targeting and drug delivery are some of the applications of these AuNPs, but endothelial extracellular matrices&#39; defensive properties hamper particle uptake. To address this issue, we describe a synthesis method for ultrasmall gold nanoparticles to improve vascular delivery, with customizable functional groups and polymer lengths for further adjustments. The protocol yields 2.5 nm AuNPs that are capped with tetrakis(hydroxymethyl)phosphonium chloride (THPC). The replacement of THPC with hetero-functional polyethylene glycol (PEG) on the surface of the AuNP increases the hydrodynamic radius to 10.5 nm while providing various functional groups on the surface. The last part of the protocol includes an optional addition of a fluorophore to allow the AuNPs to be visualized under fluorescence to track nanoparticle uptake. Dialysis and lyophilization were used to purify and isolate the AuNPs. These fluorescent nanoparticles can be visualized in both in vitro and in vivo experiments due to the biocompatible PEG coating and fluorescent probes. Additionally, the size range of these nanoparticles render them an ideal candidate for probing the glycocalyx without disrupting normal vasculature function, which may lead to improved delivery and therapeutics.

We describe a method of synthesizing biocompatible 10-nm gold nanoparticles, functionalized by coating poly-ethylene glycol onto the surface. These particles can be used in vitro and in vivo for delivering therapeutics to nanoscale cellular and extracellular spaces that are difficult to access with conventional nanoparticle sizes.

تركيب 10 نانومتر فونكتيوناليزيد المغلفة البوليمر جزيئات الذهب لاستهداف البطانة وإيصال الأدوية

Gold nanoparticles (AuNPs) have been used extensively in medical research due to their size, biocompatibility, and modifiable surface. Specific targeting ...

Assembly and Characterization of Biomolecular Memristors Consisting of Ion Channel-doped Lipid Membranes

The ability to recreate synaptic functionalities in synthetic circuit elements is essential for neuromorphic computing systems that seek to emulate the cognitive powers of the brain with comparable efficiency and density. To date, silicon-based three-terminal transistors and two-terminal memristors have been widely used in neuromorphic circuits, in large part due to their ability to co-locate information processing and memory. Yet these devices cannot achieve the interconnectivity and complexity of the brain because they are power-hungry, fail to mimic key synaptic functionalities, and suffer from high noise and high switching voltages. To overcome these limitations, we have developed and characterized a biomolecular memristor that mimics the composition, structure, and switching characteristics of biological synapses. Here, we describe the process of assembling and characterizing biomolecular memristors consisting of a 5 nm-thick lipid bilayer formed between lipid-functionalized water droplets in oil and doped with voltage-activated alamethicin peptides. While similar assembly protocols have been used to investigate biophysical properties of droplet-supported lipid membranes and membrane-bound ion channels, this article focuses on key modifications of the droplet interface bilayer method essential for achieving consistent memristor performance. Specifically, we describe the liposome preparation process and the incorporation of alamethicin peptides in lipid bilayer membranes, and the appropriate concentrations of each constituent as well as their impact on the overall response of the memristors. We also detail the characterization process of biomolecular memristors, including measurement and analysis of memristive current-voltage relationships obtained via cyclic voltammetry, as well as short-term plasticity and learning in response to step-wise voltage pulse trains.

Soft, low-power, biomolecular memristors leverage similar composition, structure, and switching mechanisms of bio-synapses. Presented here is a protocol to assemble and characterize biomolecular memristors obtained from insulating lipid bilayers formed between water droplets in oil. The incorporation of voltage-activated alamethicin peptides results in memristive ionic conductance across the membrane.

الجمعية وتوصيف ميمريستورس الجزيئية البيولوجية تتكون من الأغشية الدهنية قناة أيون يخدر

The ability to recreate synaptic functionalities in synthetic circuit elements is essential for neuromorphic computing systems that seek to emulate the ...