Cell growth on fiber surfaces is an important aspect of many applications of technical textiles. The need to prevent clogging in artificial blood vessels or in textiles used for blood or water filtration as well as the anti-fouling properties of outdoor technical textiles are examples in this context. Since the adsorption of proteins forms the initial step of cell growth, a promising way to avoid biofouling is to prohibit protein adsorption by means of a suitable, permanent and non-toxic surface functionalization. Today, the deposition of poly(ethylene glycol)s (PEGs) is a well-known approach to decrease non-specific protein adsorption. In this work, a photo-chemical method to graft or cross-link PEGs on fiber surfaces was studied. Monomethacrylated PEG300MA and PEG2080MA as well as dimethacrylated PEG400DMA and PEG600DMA were considered, the numbers indicate average molar mass in g/mol. Textile fabrics made of poly(ethylene terephthalate) (PET) were impregnated with solutions of the PEGs and irradiated using either a KrCl* or a XeCl* excimer lamp (emission wavelengths 222 or 308 nm, respectively). Surface properties of the treated textiles were characterized as a function of process conditions using various surface sensitive analyses. UV cross-linking of PEG400DMA resulted in the deposition of a thick layer which effectively masked the texture of the fabric and its pore system. Much less coverage was observed in case of monomethacrylated PEGMAs, with a significant reduction in drop penetration time already after deposition of a marginal layer (less than 0.01 mg/mg). Highest reductions in adsorption of bovine serum albumin (BSA) were observed for samples prepared using PEG300MA or PEG400DMA under conditions where also the drop penetration time was at its minimum. The longer chain PEG2080MA was less effective. All results show clearly that the protein adsorption tendency can be significantly reduced by choice of suitable combinations of PEGylated monomer and UV irradiation conditions. (C) Koninklijke Brill NV, Leiden, 2011