Abstract: Ascorbic acid sensor based on molecularly imprinted polymer (MIP) is reported for sensitive and selective analysis, without any cross-reactivity or matrix effect, in aqueous, blood serum and pharmaceutical samples. The sensor was developed by the direct coating of ascorbic acid-imprinted polymer, prepared from melamine and chloranil, on the surface of a hanging mercury drop electrode (HMDE) at +á0.4áV (vs. Ag/AgCl). The molecular recognition of ascorbic acid was highly specific using non-covalent (hydrophobically driven hydrogen-bonding and electrostatic) interactions. The analyte was preconcentrated and oxidised instantaneously in the imprinted polymer layer giving voltammetric signal on cathodic stripping at optimised operational conditions: accumulation potential +á0.4áV (vs. Ag/AgCl), polymer deposition time 120ás, template accumulation time 120ás, pH 7.0, scan rate 10ámV s-á1, pulse amplitude 25ámV. The proposed MIP sensor is able to enhance sensitivity substantially so as to detect serum ascorbic acid level as low as 0.26áng mL-á1 (R.S.D. 0.5%, S/N 3) for the diagnosis of hypovitaminosis C (Vitamin C deficiency)
Template and target information: ascorbic acid, vitamin C
Author keywords: voltammetric sensor, ascorbic acid, Molecularly imprinted polymerisation, differential pulse, Cathodic stripping voltammetry