Ion-Selective Electrodes for Potentiometric Determination of Ranitidine Hydrochloride, Applying Batch and Flow Injection Analysis Techniques

Novel flow injection spectrophotometric determination of ranitidine in pharmaceuticals

A novel flow injection spectrophotometric determination of ranitidine in pharmaceuticals is reported. The method is based on a compound formed in a reaction using ranitidine with and potassium permanganate in neutral media, which can be monitored at 430 nm. Under optimal conditions, an analytical curve was constructed, which was linear in the range between 5.0 × 10−5 and 1.0 × 10−3 mol L−1 with a detection limit of 1.0 × 10−5 mol L−1. In addition, the sample throughput was 60 h−1 and the obtained results for commercial formulation samples by applying the proposed method were in good agreement with labeled values and those obtained by a reference method at a 95% confidence level.

Simultaneous determination of ranitidine and metronidazole in pharmaceutical formulations at poly(chromotrope 2B) modified activated glassy carbon electrodes

A simple and sensitive electrochemical method for the simultaneous and quantitative detection of ranitidine (RT) and metronidazole (MT) was developed, based on a poly (chromotrope 2B) modified activated glassy carbon electrode (PCHAGCE). The PCHAGCE showed excellent electrocatalytic activity toward the reduction of both RT and MT in 0.1 mol/L phosphate buffer solution (pH 6.0). The peak-to-peak separations for the simultaneous detection of RT and MT between the two reduction waves in cyclic voltammetry were increased significantly from ~0.1 V at activated GCE, to ~0.55 V at PCHAGCE. By differential pulse voltammetry techniques, the reduction peak currents of RT and MT were both linear over the range of 1.0 × 10⁻⁵–4.0 × 10⁻⁴ mol/L. The detection limits (S/N = 3) were 5.4 × 10⁻⁷ mol/L and 3.3 × 10⁻⁷ mol/L for RT and MT, respectively. The modified electrode was successfully applied to the determination of RT and MT in pharmaceutical preparations and human serum as real samples with stable and reliable recovery data.

A novel method for ranitidine hydrochloride determination in aqueous solution based on fluorescence quenching of functionalised CdS QDs through photoinduced charge transfer process: spectroscopic approach

A novel method for the quantitative determination of ranitidine hydrochloride (RNH) based on the fluorescence quenching of functionalised CdS quantum dots (QDs) by RNH in aqueous solution was proposed. The method is simple, rapid, specific and highly sensitive with good precision. The thioglycolic acid (TGA)-capped CdS QDs were synthesized from cadmium nitrate and sodium sulfide in alkaline solution. Under the optimal conditions, the Stern-Volmer calibration plot of F(0)/F against concentration of RNH was linear in the range of 0.50-15.0 μg mL(-1) with a correlation coefficient of 0.996. The limit of detection (LOD) was 0.38 μg mL(-1). The method was satisfactorily applied to the direct determination of RNH in pharmaceutical formulations with no significant interference from excipients. The results were found to be in good agreement with those obtained by the reference method and the claimed value. The accuracy and reliability of the method were further ascertained by recovery studies via the standard-addition method, with percentage recoveries in the range of 98.47 to 102.30%. The possible fluorescence quenching mechanism for the reaction was also discussed.