Surface studies of a biomaterial for the development of a biosensor for the detection of trace metals

Polymeric mediators have been used in biosensor development. However, the synthesis of the polymeric mediators is tedious. To reduce the cost of biosensors organic polymer constituents, there is a search for low cost alternatives. Maize tassel (MT) has shown its potential to adsorb trace metals from aqueous solution. But before MT can be put into use in biosensor development, its characteristics properties need to be known. In this study, we report the surface characterization of maize tassel with respect to the morphology, dispersion, elemental composition and adsorption trends. The BET results indicate that the powdered material is mesoporous with specific surface area (S_BET), of 2.52 m²/g. Functional groups, -NH ₂, -C=O and -COOH were identified by FTIR analysis. Zeta potential study indicates that maize tassel possesses positive Zeta potential at pH<5.5 and negative Zeta potential at pH>5.5, and these amount to Zeta potential of 0 to ±5mV. High-resolution scanning electron microscopy (HRSEM) reveals a microstructure showing predominantly flattish rod like particles. Energy dispersive x-ray (EDX) shows high percentage levels of Al, Mg and Si with potential to form organometallic compounds. The presence of amino groups would form a linkage entry of the enzyme into MT.