Development and validation of a fluorescence spectroscopic method for the assessment of riboflavin in pharmaceutical formulations

Riboflavin is an essential water-soluble vitamin involved in numerous metabolic and physiological functions. Its accurate quantification in pharmaceuticals, food products, and biological samples is critical for quality control and nutritional evaluation. In the present study, a simple, economical, accurate, precise, and reproducible difference fluorescence spectrophotometric method has been developed and validated for the estimation of riboflavin in bulk and pharmaceutical dosage forms. The method was validated in accordance with ICH guidelines, including assessments of linearity, precision, accuracy, specificity, limit of detection (LOD), and limit of quantitation (LOQ). A standard calibration curve was generated using riboflavin concentrations ranging from 0.01 ppm to 0.1 ppm in 0.1N acetic acid, exhibiting adherence to Beer-Lambert’s law. The calibration curve displayed excellent linearity, with a correlation coefficient (r²) of 0.9997 and a regression equation of y = 6002.7x + 105.03. Precision was confirmed by low relative standard deviation (RSD) values from intra-day and inter-day measurements across three concentration levels. Accuracy, determined by recovery studies, was within an acceptable range of 99.71% to 107.17%. The LOD and LOQ were found to be 0.094 ppm and 0.2877 ppm, respectively, indicating the method’s high sensitivity. Specificity testing demonstrated that the method distinctly quantified riboflavin without interference from excipients. The validated fluorescence spectrophotometric method offers a reliable and sensitive approach for riboflavin determination. Due to its simplicity and cost-effectiveness, this method is suitable for routine quality control in pharmaceutical industries as well as for nutritional analysis in food and biological samples.