Chemical modification of silicon surfaces for biological applications

The attachment of poly(ethylene glycol) to porous Si surfaces via Si–C bonds using simple chemical techniques and commercially available starting materials is described. Poly(ethylene glycol) (PEG) is often used to prevent nonspecific binding for a variety of biological applications. The covalent attachment of a short‐chain PEG linker leads to a hydrophilic surface that is capable of admitting sucrose and bovine serum albumin (BSA) while leaving an acid terminus that can be used for further biological modification. Response of the linker‐modified porous Si surface to introduction of sucrose in aqueous solutions is assessed. This PEG linking chemistry should also be a generally useful biological attachment scheme that can be applied to crystalline silicon surfaces. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)