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Technical News
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| Activities |
| Member of AOAC method Committee for Dietary Supplement
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| Active participant in Dietary Supplement Task Force
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| Official contractor for NIH through BPA program (Blanket Purchase Agreement) |
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| Completed Single Lab Validation of
Enzymatic-HPLC Method for Chondroitin Sulfate Assay funded by NIH, and the paper is going to be published on Journal of AOAC |
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| Developed
Pre-Column Derivatization Method for Glucosamine Assay funded by NIH, and the paper have been published on Journal of AOAC |
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| Identification and Quantification of Oversulfated Chondroitins in Heparin and Regular Chondroitins |
Regarding the current issue of oversulfated chondroitins mixed in heparing and other bio-products, Analytical Laboratories in Anaheim has the ability to do the following work to distinguish the oversulfated chondroitins in the natural bio-products.
- How to Distinguish Oversulfated Chondroitins from Heparin
Chondrotins can be oversulfated manually. The oversulfated chondroitin sulfate B (dermatan sulfate) shows a similar anticoagulant activity as heparin. The main difference between heparin and oversulfated chondroitins is linkage between monomer saccharides. A α(1->4) bond links the heparin monomers.
For oversulfated chondroitins the disaccharides units are linked by a β(1->3) bound which can be digested by chondroitinases. After enzymatic digestion the produced unsaturated multiple sulfate disaccharides can be separated from mono sulfate disaccharides produced from regular chondroitin sulfate if there is any by HPLC. HPLC-UV at 232 nm can quantify chondroitin sulfated and oversulfated chondroitins after digestion. Heparin will not be digested by chondroitinases still existing as polymer in the sample.
- How to Distinguish Oversulfated Chondroitins from Regular Chondroitin Sulfat
Both chondroitin sulfate and oversulfated chondroitin can be digested by chondroitinases respectively. The multiple sulfate disaccharides produced from oversulfated chondroitins show longer retention on HPLC. It is easy to identify and quantify oversulfated disaccharides by HPLC-UV.
Chondroitin sulfate from marine origins contains some multiple sulfate disaccharides. However the HPLC profile of manual oversulfated chondroitins and natural marine CS is totally different.
In case of oversulfated dermatan is spiked in regular CS, a specific chondroitinase B (dermatanase) can be used to digest the sample. After digestion, only dermatan and oversulfated dermatan are fragmented, other CS will not be affected.
- Typical HPLC Chromatogram of Single and Multiple Sulfate Disaccharides
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