Capillary Electrophoresis with Diode Array Detection for the Quantification of Triptorelin and Lanreotide in Pharmaceutical Quality Control: Development, Validation, Greenness and Practicality Evaluation

Abstract Aim Capillary electrophoresis (CE)-based methods hold significant potential for routine use in pharmaceutical quality control (QC) laboratories. Therefore, this study aimed to develop a novel, green, and simple hydrodynamically open-system capillary zone electrophoresis method with diode-array detection (CZE-DAD) for the simultaneous analysis of lanreotide and triptorelin in a single electrophoretic run and to objectively evaluate the analytical technique’s greenness and practicality for application in the pharmaceutical QC settings. Materials and Methods The two therapeutic peptides were analysed using a commercially available CZE-DAD analytical system. The separation process was optimised by changing the composition and concentration of the background electrolyte (BGE). The developed method was validated in accordance with the International Conference on Harmonisation (ICH) Q2(R1) guidelines, and Diphereline ® (powdered form for injection, 0.1 mg of triptorelin acetate) was used as a real dosage form of triptorelin. Greenness and practicality were evaluated using Green Analytical Procedure Index (GAPI), Analytical GREEnness (AGREE), and Blue Applicability Grade Index (BAGI) metrics. Results The optimised method utilised 250 mmol/L formic acid as the BGE, achieving high separation efficiency and short migration times, where both the peptides were analysed in <5 min. The method showed excellent linearity ( r 2 > 0.99), precision (relative standard deviation [RSD] <7.1%), and accuracy (92.7%–113.6%). The limit of detection (LOD) and limit of quantification (LOQ) were determined to be 0.5 μg/mL and 2 μg/mL, respectively. The method was also found to be environmentally friendly, with high scores achieved in both the GAPI and AGREE assessments, while also being practical, with a BAGI score of >60. Conclusions The newly developed CZE-DAD method proved to be a reliable, efficient, and environmentally sustainable alternative to liquid chromatography (LC)-based methods for the analysis of lanreotide and triptorelin. The method’s acceptable validation parameters and favourable greenness and practicality scores support its high application potential in pharmaceutical QC laboratories.