A New Facile Assay For Formaldehyde Using Voltammetry

Formaldehyde is widely used in hospital and agriculture.  In this study an electrochemical sensor for formaldehyde using a dye has been developed. The sensing is based on the formaldehyde interaction with the dye – thionyl acetate (TA) in neutral media. Comparing with current existent methods for formaldehyde, our proposed  approach is simple and fast.  The mechanism of formaldehyde on the surface of the electrode was investigated by cyclic voltammetry.  The voltammetric response of formaldehyde can occur in neutral buffer with the highest sensitivity. The surface electrochemical reaction of formaldehyde on carbon, platinum, and other noble metal electrodes results in the formation of a strongly adsorbed intermediate on the electrode surface. Formaldehyde showed linear concentrations in the range of micromolarity level.  In this study we also developed a commercial pencil “sensor” for adenine, which possesses nearly the same response as regular carbon but with the ease of surface regeneration to overcome the strong adsorption of the surface product.  Our presented approach represents a novel, simple, and cost-effective alternative to formaldehyde assay.   This work was supported by NASA-TSGC-NIP, SACP-UARP, UHD-ORC, Brown Foundation, and Welch Grant ( BJ-0027 ).