Surface modification

About: Surface modification is a research topic. Over the lifetime, 35544 publications have been published within this topic receiving 859567 citations.

Functionalization of surfaces by water-accelerated atom-transfer radical polymerization of hydroxyethyl methacrylate and subsequent derivatization

Abstract: We report the synthesis of unusually thick poly(2-hydroxyethyl methacrylate) (PHEMA) films on gold surfaces by surface-initiated atom transfer radical polymerization (ATRP). Polymerization from the surface occurs rapidly at room temperature in aqueous media, resulting in the formation of 700 nm thick polymer films in just 12 h. Control experiments using neat monomer and catalyst (no water) yield films with thicknesses of only 6 nm, demonstrating the accelerating effect of water on surface-initiated ATRP. Kinetic studies reveal a nearly linear increase in thickness with reaction time, indicating that chain growth from the surface is a controlled process with some “living” character. A second block can be grown from dormant initiators at the end of PHEMA chains, providing further evidence of “living” chain ends. Derivatization of the hydroxyl groups of grafted PHEMA with a variety of molecules allows dense functionalization of these films. Reflectance FTIR spectroscopy shows a virtually quantitative yield i...

Covalently Dye-Linked, Surface-Controlled, and Bioconjugated Organically Modified Silica Nanoparticles as Targeted Probes for Optical Imaging

Abstract: In this paper we report the synthesis and characterization of organically modified silica (ORMOSIL) nanoparticles, covalently incorporating the fluorophore rhodamine-B, and surface-functionalized with a variety of active groups. The synthesized nanoparticles are of ultralow size (diameter ∼20 nm), highly monodispersed, stable in aqueous suspension, and retain the optical properties of the incorporated fluorophore. The surface of the nanoparticles can be functionalized with a variety of active groups such as hydroxyl, thiol, amine, and carboxyl. The carboxyl groups on the surface were used to conjugate with various bioactive molecules such as transferrin, as well as monoclonal antibodies such as anti-claudin 4 and anti-mesothelin, for targeted delivery to pancreatic cancer cell lines. In vitro experiments have revealed that the cellular uptake of these bioconjugated (targeted) nanoparticles is significantly higher than that of the nonconjugated ones. The ease of surface functionalization and incorporation ...

Surface modification for PDMS-based microfluidic devices

Abstract: This review focuses on advances reported from April 2009 to May 2011 in PDMS surface modifications for the application in microfluidic devices. PDMS surface modification techniques presented here include improved plasma and graft polymer coating, dynamic surfactant treatment, hydrosilylation-based surface modification and surface modification with nanomaterials such as carbon nanotubes and metal nanoparticles. Recent efforts to generate topographical and chemical patterns on PDMS are also discussed. The described surface modifications not only increase PDMS wettability, inhibit or reduce non-specific adsorption of hydrophobic species onto the surfaces in the act, but also result in the display of desired functional groups useful for molecular separations, biomolecular detection via immunoassays, cell culture and emulsion formation.

Surface modification of polymers by grafting

Abstract: Recently a variety of technologies have been proposed for improving surface properties of polymers. Among them is surface grafting of polymers. Although this is a rather new technology, polymer surface grafting offers versatile means for providing existing polymers with new functionalities such as hydrophilicity, adhesion, biocompatibility, conductivity, anti-fogging, anti-fouling, and lubrication. This review article describes various methods of grafting and grafted surface characterizations. Medical and non-medical applications connected with this polymer surface grafting are also presented referring to recent publications.