Comparative Analytical Evaluation of a Green UV–Visible Spectrophotometric Method with a Reported RP-HPLC Method for the Quantitative Estimation of Loperamide Hydrochloride

The comparative assessment of practical characteristics demonstrated that the developed UV–Visible spectrophotometric method required simpler instrumentation, lower operational cost, reduced solvent consumption, and minimal analytical waste generation compared with the reported RP-HPLC method. In contrast, the RP-HPLC method offered superior chromatographic selectivity but required sophisticated instrumentation, organic mobile phases, and greater operational resources. Both analytical procedures were considered suitable for routine pharmaceutical quality control; however, the developed UV method offered additional advantages in terms of operational simplicity and environmental sustainability.

DISCUSSION

The present study compared a developed green UV–Visible spectrophotometric method with a validated RP-HPLC method for the quantitative estimation of loperamide hydrochloride. Both analytical methods demonstrated satisfactory validation characteristics and fulfilled the essential requirements for pharmaceutical quality control. However, significant differences were observed in terms of analytical principle, operational complexity, environmental sustainability, and practical applicability.

The developed UV–Visible spectrophotometric method demonstrated satisfactory linearity, accuracy, precision, and robustness, indicating its suitability for routine quantitative analysis of loperamide hydrochloride. Although the RP-HPLC method exhibited a marginally higher correlation coefficient (R² = 0.999), the difference in linearity between the two methods is unlikely to be of practical significance for routine quality control, as both methods satisfied the acceptance criteria recommended by the International Council for Harmonisation (ICH) for analytical method validation.

Sensitivity is an important consideration when selecting an analytical method. The RP-HPLC technique is generally recognized for its high selectivity because chromatographic separation minimizes potential interference from excipients and degradation products. In contrast, UV–Visible spectrophotometry relies on direct absorbance measurement and therefore requires careful selection of analytical conditions to ensure adequate specificity. Nevertheless, the validation results obtained for the developed UV method demonstrated that reliable quantitative estimation could be achieved under the optimized analytical conditions, making the method suitable for routine pharmaceutical analysis.

Operational simplicity represents one of the principal advantages of the developed UV–Visible spectrophotometric method. Sample preparation was straightforward, analysis was completed within a shorter period, and the method required only commonly available laboratory instrumentation. In contrast, the RP-HPLC method required specialized chromatographic equipment, preparation of mobile phase, column conditioning, and greater technical expertise. These operational differences directly influence analytical cost, instrument maintenance, and laboratory throughput, particularly in quality control laboratories processing a large number of routine samples.

Environmental sustainability has become an increasingly important consideration in pharmaceutical analysis. The developed UV method employed a simplified analytical procedure with lower solvent consumption and reduced chemical waste generation. In comparison, the RP-HPLC method utilized organic mobile phase components, resulting in higher solvent consumption and increased analytical waste. Consequently, the UV method demonstrated a more environmentally sustainable analytical approach while maintaining satisfactory analytical performance for routine applications.

From an industrial perspective, both analytical methods possess distinct advantages depending on the intended application. RP-HPLC remains the preferred technique when high chromatographic selectivity, impurity profiling, or stability-indicating analysis is required. Conversely, the developed UV–Visible spectrophotometric method provides an economical and environmentally friendly alternative for routine assay and dissolution testing where rapid analysis, operational simplicity, and reduced analytical cost are of primary importance.

Overall, the comparative evaluation demonstrated that the developed green UV–Visible spectrophotometric method achieved analytical performance comparable to the validated RP-HPLC method for routine quantitative estimation of loperamide hydrochloride. While RP-HPLC offers superior chromatographic capability, the developed UV method provides substantial advantages in terms of simplicity, cost-effectiveness, environmental sustainability, and ease of implementation, making it a suitable analytical alternative for routine pharmaceutical quality control.

CONCLUSION

The present comparative analytical evaluation demonstrated that both the developed green UV–Visible spectrophotometric method and the reported RP-HPLC method are suitable for the quantitative estimation of loperamide hydrochloride and satisfy the essential analytical validation requirements for pharmaceutical quality control. The RP-HPLC method exhibited excellent chromatographic performance and analytical reliability, making it highly suitable for applications requiring superior selectivity and chromatographic resolution. Conversely, the developed UV–Visible spectrophotometric method provided comparable analytical performance while offering significant practical advantages, including simplified sample preparation, lower operational cost, reduced analysis time, lower solvent consumption, and improved environmental sustainability.

The comparative assessment indicated that the developed UV method represents a practical and economical alternative for routine quality control analysis of loperamide hydrochloride, particularly in laboratories where rapid analysis and cost-effective operation are important considerations. Although RP-HPLC remains the preferred technique for complex analytical applications such as impurity profiling and stability studies, the developed UV–Visible spectrophotometric method demonstrated adequate accuracy, precision, and robustness for routine pharmaceutical analysis. Overall, the findings of this study support the selection of analytical methods based on their intended application, available laboratory resources, and analytical requirements rather than analytical sensitivity alone.

ACKNOWLEDGEMENTS

The authors sincerely thank Vamsi Labs Ltd., Solapur, Maharashtra, India, for providing the gift sample of loperamide hydrochloride used in this study. The authors also express their gratitude to the D.S.T.S. Mandal’s College of Pharmacy, Solapur, Maharashtra, India for providing the necessary laboratory facilities and instrumental support to carry out this research successfully.

CONFLICT OF INTEREST

The authors declare that there is no conflict of interest regarding the publication of this manuscript.

FUNDING

The authors received no external financial support for this research.

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