Search

A novel platinum nanoparticle-modified graphite pencil electrode (PtNP-GPE) for a non-enzymatic determination of H 2 O 2 is proposed. The PtNP-GPE is prepared by heating a GPE in an aqueous solution of ammonium tetrachloroplatinate(II) and ascorbic acid at 75 °C for 15 min. Both unmodified and PtNP-GPE are characterized using field-emission-SEM and cyclic voltammetry. The PtNP-GPE showed better electrocatalytic properties toward the electrochemical redox reaction of H 2 O 2 than that of the unmodified GPE. The PtNP-GPE amperometric response is tested at four different potentials (+0.7, +0.5, −0.2 and −0.3 V vs. Ag/AgCl reference electrode). Taking into consideration both the intensity of the amperometric response and detector stability, the applied potential of +0.5 V is the best among the tested potentials. The PtNP-GPE amperometric response of H 2 O 2 at +0.5 V is linear from 10 to 110 μM ( R 2 = 0.999) with a detection limit of 3.6 μM. [ABSTRACT FROM AUTHOR]

A novel nanoacetylene black coated the surface of graphite pencil lead electrode (nano-AB/GPLE) is successfully constructed. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) indicated that the new designed nano-AB/GPLE possessed a fast electron transfer compared with the bare GPLE and enhanced electrochemical response toward electroreduction of antiandrogens flutamide (FLU) and cyproterone acetate (CPA) simultaneously. From the nano-AB/GPLE, two well separated reduction signals of coexistence FLU and CPA at nano-AB/GPLE were obtained. Electrochemical sensing of FLU and CPA in the presence of the physiological common interferents at nano-AB/GPLE was examined and confirmed the selectivity for the detection analysis of the two antiandrogens without cross interference of biological compounds. The limits of detection for coexistence of FLU and CPA are 1.39 nM and 4.74 nM, respectively. Finally, the applicability of the designed sensor is performed for detection of the two antiandrogens FLU and CPA simultaneously in pharmaceutical tablets and biological fluids with good accuracy and precision. A novel disposable electrochemical sensor based on nanoacetylene black (nano-AB) coated graphite pencil lead electrode (nano-AB/GPLE) was fabricated. The new sensor was applied for the simultaneous determination of the prostate anticancer drugs flutamide (FLU) and cyproterone acetate (CPA) in real samples. Unlabelled Image • A new design of a mechanical pencil holder was constructed to reduce the voltammetric analysis time usage. • A novel disposable sensor based on nano-AB coated graphite pencil lead electrode (nano-AB/GPLE) was fabricated. • The sensitive sensor was applied for the determination of antiandrogens flutamide and cyproterone acetate in real samples. • The new electrode showed good stability, sensitivity and selectivity and low detection limits [ABSTRACT FROM AUTHOR]