Reusable Enzymatic Strip for Detection of Arsenic

HIGHLIGHTS

• Arsenic is considered as one of the highly hazardous elements in the environment and a serious carcinogen for the human health.

• An enzymatic method has been described by using arsenite oxidase for arsenic detection.

• Residual activity of the immobilized enzyme was 43% of the initial activity after being recycled 10 times.

Abstract

Arsenic is considered as one of the highly hazardous elements in the environment and a serious carcinogen for the human health. More attention has taken towards the arsenic due to its presence in ground water in India, China, Bangladesh, Inner Mongolia and several other regions of the world. It’s been a challenge to remove arsenic due to the lack of its efficient detection approach in the complicated environmental matrix. The proposed method describes an enzymatic method for arsenic determination using arsenite oxidase, which catalyzes the oxidation of arsenite to arsenate. Hence, a colorimetric PVC strip with immobilized arsenite oxidase has been developed to detect the arsenic concentration and also having potential for the field-testing. The influence of the optimal conditions i.e. pH, temperature, storage stability, and reusability of free and immobilized enzyme were evaluated and compared. The results have shown that the stabilities were significantly enhanced compared with free counterpart. Residual activity of the immobilized enzyme was 43% of the initial activity after being recycled 10 times. We approve that this novel low cost immobilized carrier presents a new approach in large scale applications and expected to act as a model for establishment of indigenous arsenic sensor in miniature form.

Keywords:
arsenic; arsenite oxidase; PVC strip; groundwater