No abstract

Green analytical methods have gained a growing interest in the field of pharmaceutical research to reduce impacts on the environment and enhance analysts' health safety. Chloramphenicol (CHL), dexamethasone sodium phosphate (DSP) and tetrahydrozoline HCl (THZ) form an ophthalmic ternary mixture that is co-formulated for conjunctivitis treatment. In the present work, for time saving and higher sensitivity, two green thin-layer chromatography (TLC) methods were developed for the determination of this ophthalmic ternary mixture in the absence or presence of p-nitroacetophenone (PNA), a synthetic precursor of chloramphenicol. In both proposed methods, silica gel 60 F 254 plates were used as the stationary phase. The mobile phase used for method (A) was ethanol-water-ammonia (7.0:2.5:0.5, V/V), while, for method (B), acetonitrilewater-ammonia (10.0:3.0:0.5, V/V) was used as the mobile phase. TLC separation was followed by quantitative determination of the aforementioned drugs at wavelengths 242.0 nm and 220.0 nm. Both methods were validated in compliance with the International Conference on Harmonisation (ICH) guidelines, where both methods were found to be reliable, reproducible, and selective. Statistical comparison of the developed methods was done with a reported high-performance liquid chromatography (HPLC) method where no significant difference was found. Analytical eco-scaling depends on penalty point which was calculated to be 92, 88 and 87 for methods A, B and the reported HPLC, respectively, suggesting that the proposed methods are eco-friendlier with penalty point scoring very high on the scale than the reported one.

No abstract

Green analytical procedures are gaining popularity in the pharmaceutical research area as a way to reduce environmental impact and improve analyst health safety. The current work presents a green and sensitive electrochemical carbon paste electrode that has been chemically modified with zirconium dioxide and multi-walled carbon nanotubes for estimation of pyridoxine HCl (PYR) and doxylamine succinate (DOX) using the square wave voltammetric technique. Under optimum conditions, the linearity ranges were 20.00–2000.00 ng mL−1 and 2.00–20.00 µg mL−1 for both drugs in the 1st linear segment and 2nd linear segment, respectively. Stability testing assesses how the quality of a drug substance changes over time, depending on environmental and laboratory factors. DOX was found to undergo oxidative degradation when refluxed for 7 h using 30% H2O2 and the degraded product (DOX DEG) (toxic metabolite) was successfully characterized utilizing LC–MS. The developed electrode showed selectivity for the determination of binary mixture in pure form, pharmaceutical form, and in the presence of DOX DEG and common interfering molecules with good recovery. The proposed method was found to be eco-friendlier than the reported method in terms of the use of hazardous chemicals and solvents, energy consumption, and waste generation. Graphical Abstract

Background The combination of pyridoxine HCl (PYR) and doxylamine succinate (DOX) as an antiemetic binary mixture is used to treat nausea and vomiting during pregnancy. Objective Validated, accurate, and selective two chemometric models were developed to assay binary mixture in presence of DOX oxidative degradation product (DOX DEG) which could be characterized utilizing LC-MS. Methods Partial least squares (PLS) regression and principal component regression (PCR) were selected for the determination of our binary mixture in presence of degradation. To exhibit a training set of twenty-five mixtures that had various percentages of tested substances in five level three variables, an experimental design was chosen. Set of eighteen synthetic mixtures in the concentration range 10.0–50.0 μg/mL,/12.00–20.0 μg/mL and 6.0–30.0 μg/mL for PYR, DOX and DOX DEG, respectively were used in the construction of the calibration models. Then set seven synthetic mixtures with different concentrations for validation models. Results In validation samples with low Root Mean Squared Error of Prediction (RMSEP), the suggested models successfully predicted the concentrations of our drugs. The models developed were evaluated by RMSEP calculation and the values obtained were 0.341, 0.196, and 0.388 for PYR, DOX, and DOX DEG respectively, using PLS. While using PCR, RMSEP calculation and the values obtained were 0.400, 0.256, and 0.375 for PYR, DOX, and DOX DEG, respectively. The developed models were validated according to ICH strategies. Conclusions The corresponding methods are suitable to determine PYR and DOX in pure form, pharmaceutical dosage form, and in the presence of DOX DEG product. Highlights The study of drug breakdown pathways is very important nowadays. So, even in the presence of degradation and extreme spectral overlapping, the suggested PLS and PCR spectrophotometric approaches were able to identify PYR and DOX.

No abstract

No abstract

Triamterene (TRI) and xipamide (XIP) mixture is used as a binary medication of antihypertension which is considered as a major cause of premature death worldwide. The purpose of this research is the quantitative and qualitative analysis of this binary mixture by green univariate and multivariate spectrophotometric methods. Univariate methods were zero order absorption spectra method (D0) and Fourier self-deconvolution (FSD), as TRI was directly determined by D0 at 367.0 nm in the range (2.00–10.00 µg/mL), where XIP show no interference. While XIP was determined by FSD at 261.0 nm in the range (2.00–8.00 µg/mL), where TRI show zero crossing. Multivariate methods were Partial Least Squares, Principal Component Regression, Artificial Neural Networks, and Multivariate Curve Resolution-Alternating Least Squares. A training set of 25 mixtures with different quantities of the tested components was used to construct and evaluate them, 3 latent variables were displayed using an experimental design. A set of 18 synthetic mixtures with concentrations ranging from (3.00–7.00 µg/mL) for TRI and (2.00–6.00 µg/mL) for XIP, were used to construct the calibration models. A collection of seven synthetic mixtures with various quantities was applied to build the validation models. All the proposed approaches quantitative analyses were evaluated using recoveries as a percentage, root mean square error of prediction, and standard error of prediction. Strong multivariate statistical tools were presented by these models, and they were used to analyze the combined dosage form available on the Egyptian market. The proposed techniques were evaluated in accordance with ICH recommendations, where they are capable of overcoming challenges including spectral overlaps and collinearity. When the suggested approaches and the published one were statistically compared, there was no discernible difference between them. The green analytical method index and eco-scale tools were applied for assessment of the established models greenness. The suggested techniques can be used in product testing laboratories for standard pharmaceutical analysis of the substances being studied.