DNA-responsive uniform latex particles based on p-chloromethylstyrene

In this study, DNA binding properties of poly(ethylenimine) (PEI)-attached uniform poly(p-chloromethystyrene) (PCMS) particles were investigated. Spherical PCMS latex particles with an average size of 1.75 mum were obtained by the dispersion polymerization of p-chloromethylstyrene (CMS). PEI was covalently attached onto the PCMS particles via a direct chemical reaction between amine and chloromethyl groups, with the equilibrium binding capacities up to 41 mg PEI/g PCMS. In aqueous media, PEI attached-uniform PCMS particles showed an irreversible aggregation behaviour in the presence of DNA. To predict unknown DNA concentration, the aggregation response of these particles to the presence of DNA was quantified by spectrophotometry. Plain PCMS and PEI attached-uniform PCMS particles were also utilized as sorbents in DNA adsorption experiments conducted at +4 degreesC in a phosphate buffer medium at pH 7.4. DNA immobilization capacities up to 45 mg DNA/g PCMS could be achieved with the PEI attached particles.