Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A reversed-phase ion-pair HPLC method for separating hyaluronic acid oligomers, using a polymeric C18 column at alkaline pH, is described. As the concentration of the ion-pairing agent tetrabutylammonium hydroxide increased, over the range of 0.01 to 0.06M, the capacity factors (k') of tetra- to dodecasaccharide decreased. The change in k', for each increment in pairing agent, increased with oligomer molecular weight. When changing mobile phase pH from 7 to 8, k' dramatically decreased and remained unchanged from pH 8 to 11. The isocratic separation was optimized to resolve tetrato dodecasaccharide at pH 9.0 in under 19 min. The postcolumn derivatizing agent 2-cyanoacetamide reacted with the reducing N-acetylglucosamine end groups of hyaluronic acid oligomers to yield reaction products that were monitored at 27 nm. In a series of control experiments using decasaccharide and N-acetylglucosamine, it was found that maximum product formation took place at pH 9 and was greatly influenced by borate buffer concentration. The optimum concentration for 2-cyanoacetamide was 0.33% and a temperature of 100 degrees C gave the best signal to noise ratio for the postcolumn reaction. The method is linear and reproducible, and has a lower limit of detection for tetrasaccharide of 20 ng (25 pmol). This system is suitable for studying the degradation kinetics of purified hyaluronic acid oligomers by bovine testicular hyaluronidase. Extension of the method to fluorescent and electrochemical detection and its applicability to other glycosaminoglycans is discussed.
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PMID:A reversed-phase ion-pair high-performance liquid chromatography method for bovine testicular hyaluronidase digests using postcolumn derivatization with 2-cyanoacetamide and ultraviolet detection. 188 31

Five amide derivatives of Hyaluronic Acid (HA) were synthesized with C8, C12, C15, C16 and C18 linear alkyl-amines. These polymers (Hyadd) were tested against thermal, oxidative and hyaluronidase degradation by means of rheological experiments and SEC analysis and compared to non-modified HA. First of all, no free hexadecylamine was detected in the treated samples, meaning that under these stressing conditions only cleavage of glycosidic bonds occurs. Then, viscoelastic properties were assessed during thermal degradation and their variation as a function of time was expressed by means of a decay constant k(G'): while no significant difference in the decrease rate was observed between Hyadd-C8 and Hyadd-C12, a marked stabilization of viscoelastic properties during thermal treatment was detected for Hyadd-C15, Hyadd-C16 and Hyadd-C18. On the other hand, no difference was observed between the MW decrease rate (kMW decay constant) of HA and Hyadd-C12 to-C18; the depolymerization takes place on the backbone of the polymers independently whether they are derivatized or not, but longer alkyl chains lead to higher viscoelasticity in the depolymerized products. Finally, both oxidative and enzymatic degradation were carried out analyzing the changes in elastic modulus and in dynamic viscosity: once again, the amide side chain came out with similar behavior to chemical cross-linked HA (HBC) and with improved performances respect to linear HA in terms of preservation of viscoelasticity after chain depolymerization.
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PMID:Hyaluronan derivatives: Alkyl chain length boosts viscoelastic behavior to depolymerization. 2391 52

An in situ forming hydrogel obtained by crosslinking of amino functionalized hyaluronic acid derivatives with divinylsulfone functionalized inulin (INU-DV) has been here designed and characterized. In particular two hyaluronic acid derivatives bearing respectively a pendant ethylenediamino (EDA) portion (HA-EDA) and both EDA and octadecyl pendant groups (HA-EDA-C18) were crosslinked through an azo-Michael reaction with INU-DV. Gelation time and consumption of DV portions have been evaluated on hydrogel obtained using HA-EDA and HA-EDA-C18 derivatives with a concentration of 3% w/v and a ratio 80/20 w/w respect to the crosslinker INU-DV. The presence of pendant C18 chains improves mechanical performances of hydrogels and decreases the susceptibility to hyaluronidase hydrolysis. Bovine chondrocytes, encapsulated during crosslinking, sufficiently survive and efficiently proliferate until 28 days of analysis.
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PMID:In situ forming hydrogels of hyaluronic acid and inulin derivatives for cartilage regeneration. 2581 85