Cibacron Blue F3G-A-attached monosize poly(vinyl alcohol)-coated polystyrene microspheres for specific albumin adsorption

Abstract

Monosize polystyrene (PS) microbeads (4 μm in diameter) were produced by phase inversion polymerization of styrene in ethanol-methoxyethanol medium. They were coated with poly(vinyl alcohol) (PVAL) by adsorption and chemical cross-linking to decrease the non-specific protein adsorption. Cibacron Blue F3G-A was then attached for specific protein adsorption. The adsorption conditions were optimized to increase the amount of PVAL by changing the initial concentration of PVAL, and using different types of salts at different ionic strengths. Higher amounts of PVAL (up to 19 mg PVAL/g PS) were loaded by increasing the PVAL initial concentration and by using NA 2SO 4 at a higher ionic strength (0.2). Bovine serum albumin (BSA) adsorption and desorption on these PS-based microbeads were also investigated under different conditions. PVAL coating prevented the non-specific BSA adsorption. A higher amount of BSA (up to 60 mg BSA/g dye-attached PS/PVAL) was specifically adsorbed on dye-attached PS microbeads, especially around pH 5 and lower ionic strengths (0.01). About 90% of the adsorbed BSA was desorbed in 1 h by using 0.5 M NaSCN.