DEVELOPMENT AND VALIDATION OF A MODIFIED POLARIMETRIC ASSAY METHOD FOR SMALL VOLUME SAMPLES

Abstract

Objective: The objective of the present work was to develop a method to be useful for analyzing small volume samples of an optically active compound.

Methods: The method employed quartz cuvette instead of a polarimeter tube. Quantification of optically active compound was successfully validated in terms of linearity and range, precision and robustness. The detection limit (DL) and quantitation limit (QL) were determined as per the ICH guidelines.

Results: Polarimetry generally involves the quantification of optically active compounds by measuring its ability to rotate (in terms of angle of rotation) polarized light passed through it. The plot of angle of rotation versus concentration was linear in wide range of concentration with excellent coefficient of determination of 0.9989±0.0008. The low values of % relative standard deviation (RSD) for repeatability and intermediate precision suggested an excellent precision of the developed polarimetric method. The detection limit (DL) and quantitation limit (QL) were determined were found to be 0.5025 and 1.5225 %w/v respectively.

Conclusion: A modified polarimetric method for the quantification of dextrose was successfully developed and validated. The method employed quartz cuvette instead of polarimeter tube. The method is expected to be useful in a variety of industries where dextrose finds its application. The method can also be extended to other optically active compounds.