Abstract

Normally, the pancreatic digestive enzymes are created and carried into the duodenum in an inactive form. During pancreatitis attacks, these enzymes are inhibited from reaching the duodenum, become activated while still in the pancreas, and begin to autodigest and destroy the pancreas. In order to accurately detect lipase within seconds, a square wave technique was explored without immobilizing enzyme and any other biomolecules over the electrode surface. The cyclic voltammetric (CV) technique was used to coat a carbon electrode with a thin layer of polyaniline. This modified electrode proved to be highly sensitive and specific to detect lipase between 0 and 225 IU/L, which is well within the normal physiological range. The consistency and reliability of this technique proved to be a very formidable detector of lipase present in abnormal quantities due to pancreatitis and other pathological disorders. The interference test has been performed to detect the lipase in the presence of amylase 50, 100, and 150 IU/L to understand the interference phenomenon with lipase detection. There is no significant effect of the amylase concentration over lipase detection resulting from using a modified carbon electrode. The response time of the modified carbon electrode is approximately 5 s and the electrode has shown to be stable for 4 weeks at room temperature without special storage condition.

Keywords: Lipase; Electrochemical; Square wave voltammetery; Modified electrode

Article Outline

1. Introduction

2. Experiment

2.1. Reagents

2.2. Apparatus

2.3. Procedure for polyaniline coating over carbon electrode

2.4. Assay procedure

3. Results and discussion

3.1. Preliminary investigations on bare Au, carbon, and modified carbon electrodes

3.2. Square wave voltammetric (SWV) test with modified glassy carbon electrode

3.3. Stability test of polyaniline-coated carbon electrode

3.4. Interference studies with amylase over the detection of lipase with polyaniline-coated carbon electrode

4. Conclusions

Acknowledgements

References