Development of a gradient method for sulfamethoxazole, trimethoprim, isoniazid, and pyridoxine hydrochloride in rabbit plasma through QbD-driven investigation.

The current study developed a method for quantifying four drugs-Sulfamethoxazole, Trimethoprim, Isoniazid, and Pyridoxine-in rabbit plasma. The method uses gradient liquid chromatography based on analytical quality by design. To achieve separation, a Eclip Plus C18 (250 mm × 5 mm, 4.6 µm) column with L1 packing was used, and analytes were detected at 254 nm at ambient temperature. The optimized mobile phase consisted of 50 mM potassium dihydrogen phosphate buffer (pH 6.5) and Methanol. The concentration of Methanol was 3% (0-5 min), 15% (5-15 min), 55% (15-27 min), and 3% Methanol until the end of the 30-min runtime, and the flow rate was set at 0.95 mL/min. Control Noise Experimentation was used to screen studies, revealing that flow rate, pH, and Methanol concentration significantly affected the analytical attributes. The study identified critical attributes (resolution and asymmetric factor) and developed a quality target method profile. A central composition design was used to optimize the essential parameters. The method developed for the drugs showed peaks at retention times of 6.990 min for Isoniazid, 7.880 min for Pyridoxine, 15.530 min for Sulfamethoxazole, and 26.890 min for Trimethoprim, respectively. The method was validated with linearity in the range of 10-640 ng ml-1, with R2 of 0.9993, 0.9987, 0.9993, and 0.9992 for Sulfamethoxazole, Trimethoprim, Isoniazid, and Pyridoxine, respectively.

A technique based on infrared spectroscopy for determining sulfanilamide levels sustainably: Progress and comparisons of greenness and whiteness using ComplexGAPI, AGREE, and RGB.

The study aimed to determine the potential of the infrared (IR) spectrophotometric technique for measuring the content of sulphanilamide with the sulfonamide group. The study aimed to obtain the IR spectra of sulfanilamide and use the -SO2 band at 1114.37 for the quantitative assay, determining its area under the curve (AUC). The study gives an alternative approach to existing analytical techniques that require vast amounts of organic solvents, which are costly and can be toxic, thus impacting the environment and increasing the analysis cost. The study evaluated the method's whiteness and greenness by utilizing the Complex green analytical procedure index, analytical GREEness calculator and Red Green Blue algorithm tool. The linierity was found to be 5 to 30 µg/ml. The present study has developed an infrared (IR) spectroscopic method that employs a straightforward sample preparation technique in methanol. The IR spectroscopic method's linearity range was determined to be 5-30 µg/ml. The p-value was 0.001 at 95 % confidence level assuring better recovery. This method is evaluated according to the Q2R1 ICH guideline. It is applicable to routine quality control analysis without pre-extraction using green IR spectroscopy. In conclusion, the study demonstrated that IR spectrophotometric techniques can quantify sulfanilamide while reducing the use of organic solvents, contributing to the green-and-white analytical chemistry approach. The developed methods are reliable, accurate, and cost-effective and have the potential to be implemented in routine analysis of sulfanilamide.