Particle-by-particle quantification of protein adsorption onto poly(ethylene glycol) grafted surfaces

作者：Chen Annie; Kozak Darby; Batter**y Bronwyn J; Trau Matt^*

来源：Biofouling, 2008, 24(4): 267-273.

DOI：10.1080/08927010802058471

• protein adsorption
• protein antifouling layers
• PEG grafting and characterization
• flow cytometry

The use and advantage of flow cytometry as a particle-by-particle, low sampling volume, high-throughput screening technique for quantitatively examining the non-specific adsorption of proteins onto surfaces is presented. The adsorption of three proteins: bovine serum albumin (BSA), immunoglobulin gamma (IgG) and protein G, incubated at room temperature for 2 h onto organosilica particles modified with poly(ethylene glycol) ( PEG) of increasing MW (2000, 3400, 6000, 10,000 and 20,000 g mol(-1)) and grafted amounts (0.14-1.4 mg m(-2)) was investigated as a model system. Each protein exhibited Langmuir-like, high affinity monolayer limited adsorption on unmodified particles with the proteins reaching surface saturation at 1.8, 4.0 and 2.5 mg m(-2) for BSA, IgG and protein G, respectively. Protein adsorption on PEG-modified surfaces was found to decrease with increasing amounts of grafted polymer. PEG grafting amounts > 0.6 mg m(-2) effectively prevented the adsorption of the larger two proteins (BSA and IgG) while a PEG grafting amount > 1.3 mg m(-2) was required to prevent the adsorption of the smaller protein G.

• 出版日期2008