Changes in CD of hyaluronates and chondroitins upon periodate oxidation

Changes in conformation of hyaluronate and chondroitin sulfates following periodate oxidation were studied by CD. We monitored the progressive oxidation of these polymers by periodic acid at 4°C in pH 5.6 buffer. The negative CD band of hyaluronate at 208 nm decreased in intensity upon oxidation and changed its sign after 16 h of oxidation. In contrast, the 208‐nm CD band of chondroitin sulfates decreased, but showed no change in sign even after 48 h of oxidation. A specific difference in solution conformation between hyaluronate and chondroitins may be responsible for the difference in oxidation‐induced dichroic behavior. The results are discussed in terms of available x‐ray diffraction analyses of these polymers.