We have measured the force between a weakly charged micron-sized colloidal particle and flat substrate in the presence of highly charged nanoparticles of the same sign under solution conditions such that the nanoparticles physically adsorb to the colloidal particle and substrate. The objective was to investigate the net effect on the force profile between the microparticle and flat substrate ar...

Colloidal magnetic nanoparticles are candidates for application in biology, medicine and nanomanufacturing. Understanding how these particles interact collectively in fluids, especially how they assemble and aggregate under external magnetic fields, is critical for high quality, safe, and reliable deployment of these particles. Here, by applying magnetic forces that vary strongly over the same ...

Although carbodiimides and succinimides are broadly employed for the formation of amide bonds (i.e., in amino acid coupling), their use in the coupling of peptides to water-soluble carboxylic-terminated colloidal gold nanoparticles remains challenging. In this article, we present an optimization study for the successful coupling of the KPQPRPLS peptide to spherical and rodlike colloidal gold na...

We propose a method for the synthesis of a colloidal ZnO solution with poly(N-vinylpyrrolidone) (PVP) as stabilizer. Stable colloidal solutions with good luminescence properties are obtained by using PVP as stabilizer in the synthesis of ZnO nanoparticles by a sol-gel method assisted by ultrasound. Nanoparticles with sizes of 30-40 nm in a PVP matrix are produced as a solid product. The colloid...

Lecithin, a naturally small molecular surfactant, which is widely used in the food industry, can delay aging, enhance memory, prevent and treat diabetes. The interaction between zein and soy lecithin with different mass ratios (20:1, 10:1, 5:1, 3:1, 2:1, 1:1 and 1:2) in ethanol-water solution and characterisation of zein and lecithin composite colloidal nanoparticles prepared by antisolvent co-...

We demonstrate an optical interference-based photochemical method for the high-resolution localization of nanoparticles inside colloidal crystals or other porous structures. The method specifically relies on photoinduced inversion of the colloidal crystal surface charge to drive the localized deposition of charged gold nanoparticles. 4-Bromomethyl-3-nitrobenzoic acid (BNBA) was used as a photoc...

Colloidal mesoporous silica nanoparticles asymmetrically capped with non-porous phenylsilsesquioxane have been prepared by adding phenyltriethoxysilane to an aqueous dispersion of mesostructured silica-surfactant composite nanoparticles. The integration of colloidal stability, mesoporosity and the Janus structure is quite promising for materials design applicable in various fields, including ca...

Colloidal mesoporous silica nanoparticles less than 20 nm in diameter are prepared by dialysis; this simple surfactant removal route can avoid aggregation by sedimentation-redispersion and remove cationic surfactants while retaining the original colloidal state, which is applicable to the preparation of primary nanoparticles carrying a functional organic substance.

The reduction of [Pt(COD)(CH3)2] with CO in the presence of hexadecylamine (HDA) and oleic acid (OlAc) leads to amine carbonylation and formation of an air-stable colloidal solution of N,N'-bis(hexadecyl)urea-stabilized Pt(0) nanoparticles. These air-stable colloidal solutions can be used to form thin films of Pt nanoparticles on a silicon substrate.

CytImmune Sciences, Inc. 9640 Medical Center Drive, Rockville, MD, 20850: email: [email protected] Virginia Polytechnic Institute and State University, Department of Chemistry Blacksburg, VA 24061 Colloidal gold nanoparticles represent a versatile biomedical platform. Our efforts have focused on the development of these nanoparticles into a platform technology for developing tumor targete...