Adsorptive Cathodic Stripping Voltammetric Determination of Cefoperazone in Bulk Powder, Pharmaceutical Dosage Forms, and Human Urine

The electroreduction behaviour and determination of cefoperazone using a hanging mercury drop electrode were investigated. Cyclic voltammograms of cefoperazone recorded in universal Britton-Robinson buffers pH 3–6 exhibited a single irreversible cathodic peak. The process was adsorption-controlled. Britton-Robinson buffer 0.04 M pH 4.0 was selected as a supporting electrolyte for quantitative purposes by differential pulse and square wave adsorptive cathodic stripping voltammetry. The experimental voltammetric conditions were optimized using Central Composite Face design. A reduction wave was seen in the range from −0.7 to −0.8 V. These voltammetric techniques were successfully validated as per ICH guidelines and applied for the determination of cefoperazone in its single and sulbactam containing powders for injection and statistically comparable to USP-HPLC. They were further extended to determine cefoperazone in spiked human urine with no matrix effect.

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Adsorptive cathodic stripping determination of minoxidil in pharmaceutical, cream and shampoo products

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc2011001 ◽

2011 ◽

Vol 76 (5) ◽

pp. 371-382 ◽

Cited By ~ 6

Author(s):

Farhad Ahmadi ◽

Sahar Ghasemi ◽

Mehdi Rahimi-Nasrabadi

Keyword(s):

Supporting Electrolyte ◽

Pulse Height ◽

Direct Determination ◽

Stripping Voltammetry ◽

Differential Pulse ◽

Reduction Wave ◽

Cyclic Voltammogram ◽

Topical Solution ◽

Cathodic Stripping

The cyclic voltammetric behavior of minoxidil was studied in a buffer with pH 3. Contradictory to that mentioned in a previously published work, the cyclic voltammogram of minoxidil exhibited a single 2-electron irreversible reduction wave in a buffer with pH 3. This wave was attributed to the reduction of the N→O bond. The cathodic differential pulse wave height decreased on the increase of pH till it disappeared in solution with pH 7.2. The quantitative trace determination of minoxidil was studied at a hanging mercury drop electrode by adsorptive cathodic stripping voltammetry. A fully validated sensitive procedure based on controlled adsorptive accumulation of the drug onto a HMDE was developed for its direct determination. Accumulation of minoxidil was found to be optimized in 0.1 M Britton–Robinson buffer with pH 2.0 as supporting electrolyte under the following conditions: accumulation potential –0.2 V, accumulation time 40 s, scan rate 40 mV s–1 and pulse height 50 mV. The proposed procedure was applied successfully for determination of minoxidil in its topical solution and illegal shampoo and cream. The mean recoveries of the minoxidil were 99.8, 97.8 and 96.7% and with RSD of 0.86, 1.24 and 1.89% in pharmaceutical topical solution, shampoo and cream, respectively.

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Determination of copper in whole blood by differential pulse adsorptive stripping voltammetry

Mediterranean Journal of Chemistry ◽

10.13171/mjc.2.6.2014.21.02.25 ◽

2014 ◽

Vol 2 (6) ◽

pp. 691-700 ◽

Cited By ~ 4

Author(s):

Tarik Attar ◽

Yahia Harek ◽

Lahcene Larabi

Keyword(s):

Whole Blood ◽

Supporting Electrolyte ◽

Stripping Voltammetry ◽

Differential Pulse ◽

Accumulation Time ◽

Cathodic Stripping Voltammetry ◽

Accumulation Potential ◽

Determination Of Copper ◽

Cathodic Stripping

Â A selective and sensitive method for determination of copper in blood by adsorptive differential pulse cathodic stripping voltammetry is presented. The method is based on adsorptive accumulation of the complexes of Cu (II) ions with benzenesulfonyl hydrazide onto hanging mercury drop electrode (HMDE), followed by the reduction of the adsorbed species by differential pulse cathodic stripping voltammetry. The effect of various parameters such as supporting electrolyte, concentration of benzenesulfonyl hydrazide, accumulation potential, accumulation time and stirring rate on the selectivity and sensitivity were studied. The optimum conditions for determination of copper include perchloric acid 0.03 M, concentration of benzenesulfonyl hydrazide 7.5Ã—10-5 M, the accumulation potential of -350 mV (vs. Ag/AgCl), the accumulation time of 50 s, and the scan rate of 50 mV s-1. Under optimized conditions, linear calibration curves were established for the concentration of Cu (II) in the range of 0.62-275 ng mL-1, with detection limit of 0.186 ng mL-1 for Cu (II). The procedure was successfully applied to the determination of copper ion in whole blood samples.

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