Biotech Contipro, 561 02 Dolní Dobrouč 401, Czech Republic.
Carbohydr Res. 2013 Apr 19;371:8-15. doi: 10.1016/j.carres.2013.01.025. Epub 2013 Feb 8.
Native hyaluronan (HA) has been oxidized to polyaldehyde polymers with a degree of substitution (DS) of up to 50%. Two different procedures enabling the control of the degree of substitution were followed in this study. Selective oxidation of primary hydroxyl groups of N-acetyl-D-glucosamine of hyaluronan was performed either in an aqueous solution containing AcNH-TEMPO/NaBr/NaOCl or in an aprotic solvent containing Dess-Martin periodinane (DMP). It was found that a change of reaction parameters (reaction time and temperature, type of catalyst, oxidant-to-HA ratio, presence of nitrogen, buffer type, and concentration) had an influence on the degree of substitution and molecular weight. The derivatives were characterized by MS, NMR spectroscopy, and SEC-MALLS. Degradation of hyaluronic acid by the oxidant was observed and confirmed by SEC. The effect of oxidized derivatives of hyaluronan on cells was studied by means of NIH 3T3 fibroblast viability, which indicates that prepared hyaluronan polyaldehydes are biocompatible and suitable for medical applications and tissue engineering. The function of polyaldehyde as precursor for other modification was illustrated in the reaction with lysine.
天然透明质酸（HA）已被氧化为多醛聚合物，取代度（DS）高达 50%。本研究采用两种不同的方法来控制取代度。HA 的 N-乙酰-D-葡萄糖胺上的伯羟基可以在含有 AcNH-TEMPO/NaBr/NaOCl 的水溶液中或含有 Dess-Martin 过碘烷（DMP）的非质子溶剂中进行选择性氧化。结果发现，反应参数（反应时间和温度、催化剂类型、氧化剂与 HA 的比例、氮的存在、缓冲液类型和浓度）的变化会对取代度和分子量产生影响。衍生物通过 MS、NMR 光谱和 SEC-MALLS 进行了表征。通过 SEC 观察到并证实了氧化剂对透明质酸的降解。通过 NIH 3T3 成纤维细胞活力研究了透明质酸氧化衍生物对细胞的影响，这表明制备的透明质酸多醛是生物相容的，适用于医学应用和组织工程。多醛作为其他修饰的前体的功能在与赖氨酸的反应中得到了说明。
