High-performance liquid chromatographic determination of neutraceuticals, glucosamine sulphate and chitosan, in raw materials and dosage forms Original Research Article

A simple, rapid, selective and specific high performance liquid chromatographic (HPLC) method was developed to quantitate glucosamine and its (β-1-4)-d-polymeric form chitosan. The chromatographic separation was achieved using an aminophase column and refractive index (RI) detection. The mobile phase consisted of ACN:H2O:CH3COOH (50:50:0.02) and pH was adjusted to 4.0. The standard curves for glucosamine sulphate showed linearity (r≥0.99) over the concentration range from 20 to 1000 μg ml−1 for raw materials and dosage forms. The precision of the raw material assay expressed as the relative standard deviation (R.S.D.), was less than 3% at all concentrations. Chitosan, poly-(β-1-4)-d-glucosamine compounds, was hydrolysed with 6 M HCl at 100 °C for 10 h and the released glucosamine was determined by the same HPLC method. The proposed method showed linear relation in concentration ranges of 100–500 μg ml−1. The suggested procedure was applied for the determination of glucosamine sulphate and chitosan in their dosage forms and the validity of the method was further checked by applying the standard addition technique. The method was found to be specific with good linearity, accuracy, precision and is well-suited for quantitation of glucosamine sulphate and chitosan in raw materials and pharmaceutical formulations.