Enzyme Biosensor for Detection of Formaldehyde on Carbon Nanotube-Screen Printed Electrodes Modified with Pyrenyl Groups

Formaldehyde has been recognized as a marker in diseases associated with kidneys, nerves and lungs. Our objective is to develop a novel, highly sensitive electrochemical amperometric enzyme biosensor for detection of low levels of formaldehyde. Our biosensor design involves CNTs-modified screen-printed electrodes (SPEs) with immobilized formaldehyde dehydrogenase (FDH). CNT-coated electrodes modified with non-covalently attached pyrenebutyric acid linkers were used to attach the FDH enzyme and achieve enhanced electron transfer and biosensing properties. The FDH catalyzed oxidation of formaldehyde, using NAD⁺ as the electron acceptor, yields formic acid and NADH. This was detected electrochemically using an electrochemical mediator in solution. Such electrochemical sensors upon further optimization are expected to be useful for diagnosing clinically relevant levels of small molecule disease markers and environment pollutants.

Acknowledgements: We are grateful for the financial support by the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health under Award Number R15DK103386.