In vitro analytical dissolution profiling of antiemetic delayed release tablets in two different dissolution media: Validated spectrophotometric methods versus reported HPLC

Univariate versus multivariate spectrophotometric data analysis of triamterene and xipamide; a quantitative and qualitative greenly profiled comparative study

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.

Chemometric Quality Assessment of Doxylamine Succinate With Its Degradation Product: Implementation of Two Predictive Models on UV-Spectrophotometric Data of Anti-Emetic Binary Mixture

BACKGROUND

The combination of pyridoxine hydrochloride (PYR) and doxylamine succinate (DOX) as an antiemetic binary mixture is used to treat nausea and vomiting during pregnancy.

OBJECTIVE

Two validated, accurate, and selective chemometric models were developed to assay binary mixture in the presence of DOX oxidative degradation product (DOX DEG) that could be characterized using 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 25 mixtures that had various percentages of tested substances in five level 3 variables, an experimental design was chosen. A set of 18 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 of seven synthetic mixtures with different concentrations were used in the construction of the validation models.

RESULTS

In validation samples with low root mean square 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.

A simple and sensitive LC-MS/MS method for determination of doxylamine in human plasma and its application in a bioequivalence study in healthy Chinese volunteers

A simple, rapid, sensitive and specific LC-MS/MS method was developed and validated for the quantitative determination of doxylamine in human plasma, using isotope doxylamine-d5 as internal standard (IS). The detection was conducted on a QTRAP 5500 tandem mass spectrometer coupled with electrospray ionization (ESI) source in positive ion mode. Quantification was achieved by positive electrospray ionization containing multiple reaction monitoring (MRM) transitions of m/z 271.0→182.0 for doxylamine and m/z 276.2→187.3 for IS. The mobile phase A was methanol, and mobile phase B was 20 mM ammonium acetate (0.2 % formic acid) in water, using a gradient elution procedure at a flow rate of 0.6 mL/min. The method was validated with a sensitivity of 0.500 ng/mL and a linear concentration range of 0.500-200 ng/mL. The inter-batch precision (%CV) was less than 5.4 %, and the accuracy deviation (%RE) ranged from - 10.6 % to 3.7 %; the inter-batch precision (%CV) was less than 6.6 %, and the accuracy deviation (%RE) was ranged from - 2.7 % to 0.1 %. The selectivity, sensitivity, extraction recovery, matrix effect, carryover, dilution reliability, stability and other characteristics were within the acceptable range. This validated method was successfully applied to a bioequivalence study that orally administered 25 mg of doxylamine succinate tablets in 60 healthy Chinese volunteers.

Analytical Eco-Scale for Evaluating the Uniqueness of Voltammetric Method used for Determination of Antiemetic Binary Mixture Containing Doxylamine Succinate in Presence of its Toxic Metabolite

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