Determination of chondroitin sulfate in tablets by Raman spectroscopy and near-infrared spectroscopy combined with chemometric methods

Abstract

NIR can obtain high accuracy within a wider concentration range. Raman can obtain relatively high accuracy only within a narrower concentration range.

Quantitative evaluation of sulfation position prevalence in chondroitin sulphate by Raman spectroscopy

“…These sources are of enormous interest with regards to treating neuralgia, arthritis, tinnitus, cancer, hyperlipaemia, and other conditions . Treatment outcome is directly related to the quality of the CS preparation, however the quantification of intact CS with no UV or fluorescence chromophores is difficult by normal spectral and chromatographic methods . Reliable and accurate methods for the determination of CS content are therefore important for the quality control of CS preparations.…”

“…The structural characteristics of chondroitin sulphate include heterogeneity of molecular mass and charge density due to different sites and degrees of sulfation, since CS occurs in various isomeric forms such as CS‐A (4‐sulfation in N‐acetyl‐D‐galactosamine) and CS‐C (6‐sulfation in N‐acetyl‐D‐galactosamine) . These isomeric forms exhibit functional selectivity, CS‐C (6‐sulfation) being related, for instance, with wound repair, central nervous system development, and countering infection .…”

“…Although offering high sensitivity, electrochemical methods demand strict conditions, present some difficulties in operation, and their specificity is not good. There is therefore a need for an appropriate and precise method for the quantitative analysis of CS …”

“…Raman spectroscopy allows for rapid, simple, reproducible, and nondestructive analysis and has the advantage that sample pretreatment, external markers, and preseparation are not required . It measures inelastic scattered light following the excitation of a target compound, tissue, or molecule by a monochromatic laser.…”

“…The main Raman spectroscopy peaks of C6S and C4S were both detected and identified. Liu et al (2014) determined the CS content of tablets using Raman and near‐infrared (NIR) spectroscopy methods and validated the Raman approach in quantitative analysis by comparing the results obtained with Raman and NIR . The development of a calibration and validation model to predict CS content of unknown samples was the objective.…”