The oxidative behavior of pramipexole was studied at modified electrodes in various buffer solutions and at different pH values using cyclic and square wave voltammetry. Glassy carbon electrode (GCE) was modified using graphene (GRP) and bismuth (III) oxide (Bi 2 O 3 ) nanoparticles. Different conditions were investigated to optimize the analytical methodology for determination of pramipexole in pharmaceutical formulation. Square-wave voltammograms of pramipexole showed higher current response at GRP/GCE, 88.66% and Bi 2 O 3 /GCE, 20.70% whereas; cyclic voltammograms at GRP/GCE, 82.94% and Bi 2 O 3 /GCE, 18.03% as compared to bare GCE. Electrochemical impedance spectra (EIS) showed the reduction in charge transfer resistance of modified electrodes and enhancement in current response due to higher electrocatalytic behavior of GRP/GCE and Bi 2 O 3 /GCE. The relationship between oxidation peak current and concentration of pramipexole was linear in the range of 40−300 ng mL −1 with the detection limit 12.79 ng mL −1 . The morphological characteristics of GRP and Bi 2 O 3 nanoparticles were studied by atomic force microscopy (AFM). This method was employed for quantification of pramipexole in different pharmaceutical formulations.

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A very sensitive electrochemical sensor has been developed by modification of glassy carbon electrode (GCE) with graphene (GRP) and bismuth (III) oxide (Bi 2 O 3 ) nanoparticles. The electrochemical behavior of Tranexamic acid was studied at GRP/GCE and Bi 2 O 3 /GCE using cyclic and square-wave voltammetric techniques. A well defined oxidation peak was observed in Britton-Robinson (BR) buffered solution. GRP/GCE and Bi 2 O 3 /GCE showed higher current response as compared to bare GCE. Electrochemical impedance spectra showed reduction of charge transfer resistance and higher electrocatalytic behavior of the sensors. The morphological characteristics of GRP and Bi 2 O 3 nanoparticles were studied by atomic force microscopy (AFM). GRP/GCE showed a linear response for Tranexamic acid over the concentration range of 40-400 μg/mL with the detection limit 16.57 μg/mL. Variation of scan rate revealed that the electrode process is diffusion controlled. Moreover electrode dynamics parameters were calculated and a possible reaction mechanism has been deduced. This method was employed for quantification of Tranexamic acid in different pharmaceutical formulations.

N,N-Dichloro poly(styrene-co-divinylbenzene) sulfonamide (1) reacts with 2-chloro ethyl phenyl sulfide (2), a simulant of sulfur mustard (SM), at room temperature, yielding corresponding nontoxic sulfones and sulfoxides in aqueous as well as aprotic medium. The decontamination reaction was monitored by gas chromatography, and products were identified by gas chromatography-mass spectrometry. N,N-dichloro poly(styrene-codivinylbenzene) sulfonamide was synthesized by three steps from a commercial starting material sulfonate cationexchange resin and characterized by FTIR, and TGA, and compressive strength by universal testing machine. The positive chlorine content of this polymer was checked by standard iodometry titration. The synthesized positive chlorine compound is observed to be a promising against a simulant of SM, chiefly in the situation where use of aqueous medium is precluded.