VALIDATION OF THE RIBOSE METHOD FOR DETERMINATION OF TOTAL PRP CONTENT IN MONOVALENT HIB VACCINES

Abstract

Polyribosylribitol phosphate (PRP) is an essential polysaccharide antigen in vaccines against Haemophilus influenzae type b (Hib). The Ribose method is a chemical assay described in the pharmacopoeia for the determination of PRP content in Hib vaccines. Since the method has been previously standardized, this study aimed to perform a partial validation of the Ribose method to assess its suitability for routine quality control testing. The validation parameters evaluated included repeatability, intermediate precision, limit of quantification (LOQ), and method stability under minor variations in analytical conditions. The results demonstrated that the method exhibited good repeatability and intermediate precision, with %RSD values meeting the acceptance criteria. The LOQ was determined to be 1.68 µg/mL, which is appropriate for the PRP content levels present in Hib vaccines. Statistical comparison between analysts showed no statistically significant difference (p > 0.05). Based on these findings, the Ribose method was considered suitable for routine determination of PRP content in Hib vaccines in quality control laboratories, contributing to the reliability of analytical results and ensuring vaccine quality.