SPDS Set 1 ERP Book

CHON-002

Question

Response

General

AOAC Method Number:

CHON-002

Isotachophoretic Determination of Glucosamine and Chondroitin Sulphate in Dietary Supplements, Czech Journal of Food Science 31:55-65

Method Title:

Method Author(s):

Eliska Vaclavikova and Frantisek Kvasnicka

Reviewer Name:

Kelly Reins

Capillary isotachophoretic method for the determination of chondroitin suphate in dietary supplements. Anionic analysis of chondroitin sulphate, CS, was performed using a leading electrolyte solution consisting of a mixture of 5mM HCl + 10mM glycylglycine+ 0.05% 2-hydroxyethylcellulose. The terminating solution was 10mM citric acid. The separation compartment contained a pre-separation Fluorinated ethylene propylene (FEP) capillary coupled with an analytical FEP capillary. The separation was carried out with the electro- osmotic flow suppressed. The analytes were detected by conductivity and UV (254nm) detectors. Method is for Glucosamine and CS determination. All reviewer comments are for CS only. The authors performed the validation on tablets with stated daily doses of 600 and 1200 mg CS. Capsules, syrups and powders obtained from manufacturers and domestic markets were analyzed, however, were not part of the validation. • Raw data was not submitted for the reviewer. • The validation was performed using analytical grade chemicals and reagents. The standards were purchased from Sigma and do not appear to be properly characterized. Authors reported impurities being found in the reference materials; CS-A being a mix of CS-A and CS-C. • Accuracy was performed using standard addition of CS-A at 50% and 100%. • Data on the effectiveness on sonication was not provided. Stability of sample solution in a sonicator for 30 minutes was not evaluated.

Summary of Method

Method Scope / Applicability:

General Comments About the Method: