Immobilization of <i style="">Arthrobacter</i> sarcosine oxidase onto alkylamine and arylamine glass and its application in serum sarcosine determination

Abstract

Commercial sarcosine oxidase (Sarcosine: O₂ oxidoreductase, EC 1.5.3.1) from <i style="">Arthrobacter </i>sp. has been immobilized onto alkyl and arylamine glass-beads through glutaraldehyde cross linking and diazotization with a conjugation yield of 0.86 mg/g &amp; 0.91 mg/g support and 75.8% &amp; 84.6% retention of initial activity of free enzyme, respectively. The enzyme showed decrease in optimum <i style="">p</i>H and K_m for sarcosine but increase in temperature for maximum activity and time for linearity after immobilization. The glass beads were employed for colorimetric determination of sarcosine in serum. The minimum detection limit of the method was 0.05 m<i style="">M</i>. The glass beads were reused 100-times without considerable loss of activity, when stored in distilled water at 4°C for a period of two months.