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A versatile methodology to prepare hybrid biomaterials by atom transfer radical polymerization from resin-supported peptides has been established. As an example, we have synthesized a GRGDS-functionalized poly(2-hydroxyethyl methacrylate). The peptide-polymer was characterized by solid-state (13)C NMR and GPC and found to have a number average molecular weight of 4420 and a polydispersity of 1.47. These values are comparable to those obtained from solution-phase syntheses, suggesting the ATRP reaction is successful from a peptide-conjugated solid support. Solid-state (13)C NMR was used to characterize multiple steps in the reaction, and the synthesis was found to be near quantitative. We have performed cell adhesion experiments and observed the GRGDS sequence-promoted cell adhesion, whereas unfunctionalized poly(2-hydroxyethyl methacrylate) did not. By incorporating cell-signaling moieties in materials with defined molecular architecture, it will be possible to control the interactions between polymeric materials and biological systems.

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The preparation, structure, and catalytic properties of porous zirconium phosphate/ phosphonate compounds are discussed. The crystal structure for the Zr 2 (PO 4 )(O 3 PCH 2 -CH 2 (viologen)CH 2 CH 2 PO 3 )X 3 ‚3H 2 O, X ) halide, is presented. The structure was determined ab initio from X-ray powder diffraction data and refined by Rietveld methods. The compound crystallizes with the symmetry of space group P2/c with a ) 13.589(2) Å, b ) 8.8351(9) Å, c ) 9.229(1) Å, and β ) 100.79°. The structure consists of inorganic lamellae bridged by phosphono-ethyl-viologen groups. Large pores are formed in this material, which contain one halide ion and three water molecules per formula unit. The free halide ions in these materials are readily exchanged for PtCl 4 2ions. The Pt salt was reduced to give fine metal particles inside the porous solid. These materials produce hydrogen photochemically from water using ultraviolet light. The average rate of H 2 production is 0.15 mL/h with a lower limit quantum yield of 4% based only on the ultraviolet portion of the spectrum in the presence of a sacrificial reductant (EDTA).