High-Performance Liquid Chromatography-Tandem Mass Spectrometry for the Determination of Trospium Chloride in Human Plasma and Its Application in a Bioequivalence Study

Novel approaches of erythrosine B as a food dye-derived spectroscopic probe for assessing trospium chloride in raw material and dosage form

Two facile spectroscopic methodologies were designed for estimating trospium chloride (TPM) in raw material and tablets with high operational reliability and selectivity. The methods were based on employing erythrosine B (EB) as a spectroscopic tool for ion-pair complex formation with the drug. In a mild acidic medium of Britton Robinson buffer (BRB) (pH 4.0), the ionized hydroxyl group in the reagent interacted with the ionized amine in the studied drug. Method I was based on the spectrophotometric measuring of the absorbance of the reaction product at 557 nm. Method II was based on spectrofluorimetric measuring of the quenching effect of TPM on the inherent fluorescence of EB at 550 nm (λ_ex. =528 nm). The two methods showed linearity through ranges (1.0-10.0) and (0.5-10.0) μg/mL for methods I and II, respectively. The suggested methods were exploited for analyzing TPM in Trospamexin® tablets and showed good applicability. The designed systems were validated as per ICH guidelines. Experimental conditions were modulated to obtain the best sensitivities. The quenching mechanism was investigated and the quenching constant was computed relying on Stern-Volmer equation. Environmental impact was appraised using novel metric green tools, GABI and AGREE. The suggested systems excelled over other reported methods in terms of greenness, sensitivity and cost-effectiveness.

Conductometric determination of trospium chloride by silver nitrate and phosphomolybidic acid

Two simple, accurate, sensitive and precise conductometric methods were developed for determination of trospium chloride in pure form and in pharmaceutical formulations. It is based on using two precipitating reagents; Phosphomolybdic acid (PMA) and Silver nitrate (AgNO₃). The mean recovery for Silver nitrate is in the range (98-100.95%) and for Phosphomolybdic acid in the range (98-101.69%). A molar ratio has been determined conductometrically for the two reagents, revealed (1/1) for (drug/reagent). The proposed methods were validated and successfully applied for the determination of the studied drug in pure form and in its pharmaceutical preparation. The results of the proposed methods were compared to the results of reported method with no significant difference between them.