Diazonium salt chemistry and atom transfer radical polymerization (ATRP) were combined in view of preparing new bioactive hairy diamond nanoparticles containing, or potentially containing, nitrogen-vacancy (NV) fluorescent centers (fluorescent nanodiamonds, or fNDs). fNDs were modified by ATRP initiators using the electroless reduction of the diazonium salt BF(4)(-),(+)N(2)-C(6)H(4)-CH(CH(3))-Br. The strongly bound aryl groups -C(6)H(4)-CH(CH(3))-Br efficiently initiated the ATRP of tert-butyl methacrylate (tBMA) at the surface of the nanodiamonds, which resulted in obtaining ND-PtBMA hybrids. The grafted chain thickness, estimated from X-ray photoelectron spectroscopy (XPS), was found to increase linearly with respect to time before reaching a plateau value of ca. 2 nm. These nanoobjects were further hydrolyzed into ND-PMAA (where PMAA is the poly(methacrylic acid) graft) and further decorated by bovine serum albumin through the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) coupling procedure.

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Quercetin-imprinted poly(vinyl pyridine-co-ethylene glycol dimethacrylate) cross-linked grafts were prepared by atom transfer radical polymerization (ATRP) using aryl modified gold substrates as macroinitiators. The aryl layers were first attached to Au by electrochemical reduction of the diazonium salt BF The changes in the surface chemical composition, from the neat Au to Au-MIP and Au-NIP, were monitored by XPS and polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS). Cyclic voltammetry (CV) was used to assess the specificity and selectivity of Au-MIP to detect quercetin. The detection limit was found to be better than 10 −6 mol/l with CV.

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The reversible addition-fragmentation chain transfer (RAFT) polymerization of a hydrolyzable monomer (tert-butyldimethylsilyl methacrylate) with cumyl dithiobenzoate and 2-cyanoprop-2-yl dithiobenzoate as chain-transfer agents was studied in toluene solutions at 70 8C. The resulting homopolymers had low polydispersity (polydispersity index < 1.3) up to 96% monomer conversion with molecular weights at high conversions close to the theoretical prediction. The profiles of the number-average molecular weight versus the conversion revealed controlled polymerization features with chain-transfer constants expected between 1.0 and 10. A series of poly (tert-butyldimethylsilyl methacrylate)s were synthesized over the molecular weight range of 1.0 Â 10 4 to 3.0 Â 10 4 , as determined by size exclusion chromatography. As strong differences of hydrodynamic volumes in tetrahydrofuran between poly(methyl methacrylate), polystyrene standards, and poly(tert-butyldimethylsilyl methacrylate) were observed, true molecular weights were obtained from a light scattering detector equipped in a triple-detector size exclusion chromatograph. The Mark-Houwink-Sakurada parameters for poly(tert-butyldimethylsilyl methacrylate) were assessed to obtain directly true molecular weight values from size exclusion chromatography with universal calibration. In addition, a RAFT agent efficiency above 94% was confirmed at high conversions by both light scattering detection and 1 H NMR spectroscopy. V V C 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5680-5689, 2005

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In this paper, we describe a simple and powerful way to synthesize antibacterial biomaterials with applications as implants in orthopedic surgery. Such implants are obtained by covalently grafting onto the Ti90A16 V4 alloy surface with vancomycin-functionalized nanoparticles. Nanoparticles were produced by ring-opening metathesis polymerization of α-norbornenyl-ω-vancomycin poly(ethylene oxide) macromonomers. Vancomycin is an interesting candidate because of its use in the field of implant associated infection as it is a glycopeptide which acts on bacterial walls. As a consequence, vancomycin does not need to be released for it to be active. In the first part of this paper, the synthesis and the complete characterization of these materials are described. In a second part, the in vitro antibacterial behavior is analyzed and discussed.

This work reports on the synthesis of titanium bone implants functionalized with nanoparticles (NPs) containing Arg-Gly-Asp-Cys peptide (RGDC) and shows the adhesion behavior of cells seeded on these materials. RGDC peptides were first conjugated to a norbornenyl-poly(ethylene oxide) macromonomer (Nb-PEO). Then, functional NPs with a size of ∼300 nm and constituted of polynorbornene core surrounded by poly(ethylene oxide) shell were prepared by ring-opening metathesis polymerization in dispersed medium. The grafting density of these NPs on the titanium surface is up to 2 NPs·μm(-2) (80 pmol of RGDC per cm(-2) of NP surface). Cell adhesion was evaluated using preosteoblast cells (MC3T3-E1). Results of cells cultured for 24 h showed that materials grafted with NPs functionalized with RGDC peptides enhance specific cell adhesion and can create filopodia-like structures among NP sites by stressing the cells.