Dopamine sensing with fluorescence strategy based on low temperature co-fired ceramic technology modified with conducting polymers

A convenient fluorescence sensing strategy for dopamine (DA) detection was developed based on poly dopamine (poly(DA)) formed on the surface of graphene quantum dots (GQDs). The prepared GQDs were highly luminescent due to the planar structure in aromatic molecules. The ceramic-based miniature biosensor was designed and constructed through the immobilization of laccase in an electrochemically synthesized polymer - poly[dithienotetraphenylsilane] based on low temperature co-fired ceramics technology (LTCC). This sensing system utilized the catalytic oxidation of DA to dopamine-o-quinone (DOQ), and then to poly(DA) (in alkaline conditions), which can selectively quench the strong luminescence of GQDs owing to Forster resonance energy transfer (FRET). The detection process was based on substarte oxidation in the presence of the enzyme laccase. In optimized conditions, the analytical performance illustrated high sensitivity, selectivity in a broad linear range with detection limit of 80 nM. Moreover, the method was successfully applied to test labeled pharmacological samples for DA. (C) 2017 Elsevier B.V. All rights reserved.