Abstrakt
The advantage of surface modification of voltammetric sensor for determination of catecholamine metabolites such as vanillyl mandelic acid (VMA) and homovanillic acid (HVA) is discussed. The amino-substituted coumarin derivative of Troger's base was deposi-ted on a graphite screen-printed electrode (poly(CTB)/G/SPE) cycling the electrode potential between 0 and 1.2V in 5 mL CH2Cl2 containing 1x10(-3)molL(-1) tetrabutylammonium tetrafluoroborate and 20L 0.1molL(-1) HCl.
The poly(CTB) functions as both a selective recognition and pre-concentrator agent for catecholamine metabolites. The high sensitivity of the voltammetric sensor coated by a poly(CTB) film toward VMA was achieved despite the high structural similarity between the two tested metabolites.
We presume the voltammetric detection of these species is based on selective binding by a poly(CTB) film supported by its good adherence to the electrode substrate. The voltammetric signals of VMA were observable in the concentration range 10-100molL(-1) (LOD=0.2molL(-1)) and 20-60molL(-1) (LOD=10molL(-1)) in the model and synthethic urine samples, respectively.