Radiation effect on characteristics of radiation-copolymerized methacryloyl-L-alanine methyl ester-co-2-hydroxypropyl methacrylate hydrogel and biochemical properties of ovomucoid

Abstract

Methacryloyl-D-alanine methyl ester (MA-D-AlaOMe) and methacryloyl-L-alanine methyl ester (MA-L-AlaOMe) were synthesized and polymerized by irradiation using γ-rays from a $^{60}Co$ source, in order to investigate the effect of optical isomerism on the swelling of homopolymer hydrogels which change with water content depending on temperature. These hydrogels showed a typical thermo-response such as low-temperature swelling and high-temperature deswelling, but there was no difference in swelling capacity between the two hydrogels. The stable swelling-deswelling kinetics upon repeated testing were characterized by very limited temperature ranges (0-40℃), but above this range (for example, when cycled between 10 and 70℃) the reversible thermo-response completely disappeared because of gel collapse. This defect could be overcome by copolymerization with other functional monomers and the resulting copolymers such as Methacryloyl-L-Alanine Methyl ester-co-2-Hydroxy propyl Methacrylate, Methacryloyl-L-Alanine Methyl ester-co-2-Hydroxyethyl Methacrylate, Methacryloyl-L-Alanine Methyl ester-co-2-Hydroxyethyl Acrylate, Methacryloyl-L-Alanine Methylester-co-Polyethyleneglycol #600 Dimethacrylate, Methacryloyl-L-Alanine Methyl ester-co-Polyethylene glycol #400 Dimethycrylate, and Methacryloyl-L-Alanine Methyl ester-co-Glycidyl methacrylate, exhibited a reversible thermostability superior to those of homopolymers of MA-D-AlaOMe and MA-L-AlaOMe, depending strongly upon the type of copolymer and its composition. The demethylated hydrogels gave a reversible-response not only for temperature but also for pH. The swelling-deswelling kinetics of native and demethylated hydrogels were characterized with regard to porous structure formed in the hydrogel. Radiation effects on structural and biochemical properties of ovomucoid, a protease inhibitor which is the typical allergenic protein of egg, were investigated. Trypsin inhibiting activity of ovomucoid decreased exponentially and ...