Differences in the standardization of medicinal products based on extracts of chondroitin sulfate

Objective : a comparative analysis of 6 different chondroprotectors for injection, containing chondroitin sulfate (CS) based on natural extracts. Material and methods . Five samples were studied for each CS extract. The preparations were compared on the basis of profiles of trace element composition, sulfur content, chromatographic analysis and test for total protein. In each sample, the concentration of 72 elements was determined, then averaging was performed and the variances of the content of each element were calculated. To assess the content of the protein fraction, a modified Lowry method with bicincholic acid was used. Chromatographic profiles of the studied CS extracts were measured to estimate the molecular weight distribution. Results . The studied samples differ significantly from each other in the total and individual content of sulfur, toxic and conditionally toxic microelements. According to the analysis of sulfur and trace elements, a cluster of more standardized CS extracts was identified. It was shown that the assessments of the pharmaceutical quality of the studied extracts made by the elemental profile, correspond to the assessments of the quality by the degree of proteins elimination and by the molecular weight characteristics of CS extracts. In particular, the highest total content of toxic elements was found for CS-6 (14.87±1.81 μg/l) and CS-2 (9.20±1.12 μg/l), and the lowest – for CS-4 (1.46±0.23 μg/l), CS-3 (1.92±0.33 μg/l) and CS-1 (2.98±0.25 μg/l). The highest content of protein impurities was also found in CS-6 (9.62 mg/ml) and CS-2 (6.64 mg/ml), and the lowest – in CS-1 (2.87 mg/ml). At the same time, the highest amount of sulfur was found CS-1 (6400 mg/kg) and much less – for CS-2 (370 mg/kg) and CS-6 (100 mg/kg). Significant amounts of the high-molecular fraction of CS (1–40 kDa) were found only in CS-1, and only trace amounts of high-molecular CS forms were present in CS-2 and CS-6. Conclusion . The highest content of cholesterol and sulfur and, at the same time, the lowest content of toxic microelements and proteins were distinguished by the extract obtained from the trachea of a bovine.