Imprinted polymers prepared by aqueous suspension polymerization

The feasibility of preparing cholesterol-imprinted polymers by aqueous suspension polymerization was investigated by the preparation of ethyleneglycol dimethacrylate and divinylbenzene-based beads imprinted using cholesteryl(4-vinyl)-phenyl carbonate as the template. A low volatility porogen to replace a 4:1 hexane/toluene mixture was selected on the basis of solubility parameters and consisted of dioctyl phthalate/n-decane 77:23 v/v. Beads were prepared using a range of porogen contents with the best results obtained at 5.5-6.5 mL /5 g of monomer. Uptake of cholesterol by suspension polymers was broadly similar to that of the corresponding 'bulk' polymers, but suffered from higher nonspecific binding.