Synthesis of polymer nanocomposite gels and study of bio compatibility

In this study pH sensitive nanocomposite gels composed of N-isopropylacrylamide (NIPAM) and 2-acrylamido-2-methyl-propanosulfonic acid (AMPS) have been prepared by in-situ, free-radical crosslinking copolymerization in nanosized silica solution. Myoglobin (Mb, MW 17 kDa) is used as the template bio molecule. The effects of the initial concentration and adsorption time over the Mb adsorption capacity of the nanocomposite gels have been analyzed and found to be strongly depend on the % mol AMPS in the nanocomposite gels. Isoelectric points of proteins effects the adsorption properties and maximum adsorption from aqueous solution is usually observed at their isoelectric point. The maximum Mb adsorption was observed at pH 7.0 which is closed to the isoelectric point of Mb.To study the adsorption properties of nanocomposite gels and selectivity, molecular imprinting method was investigated.Molecularly imprinted nanocomposite gels are prepared by creating three-dimensional polymeric matrix around a template molecule. After the template molecule removed, complementary cavities with respect to shape and functional groups remain.Temperature sensitive imprinted poly(N-isopropylacrylamide) nanocomposite gels were synthesis via in-situ, free radical crosslinking polymerization of corresponding monomer in nano-sized silica and five different concentration of myoglobin solution by using molecular imprinting method. Mb adsorption from Mb solutions for five different concentration was investigated by two types of nanocomposite gel systems prepared by non-imprinted and imprinted methods. Nanocomposite gels imprinted with Mb showed higher adsorption capacity and specificity for Mb than nanocomposite gels prepared by the usual procedure.At all studied conditions, the highest Mb adsorption was observed the imprinted nanocomposite gels with 12,5 %Mb. In addition, selectivity studies were also performed by using two reference molecules as fibrinogen and hemoglobin. The imprinted nanocomposite gels have higher adsorption capacity for Mb than the non-imprinted gels and also exhibited good selectivity for Mb and high adsorption rate depending on the number of Mb sized cavities.