Laboratoire d'innovation et d'analyse de bioperformance, Institut de génie biomédical, École Polytechnique, Montréal, Québec H3T1J4, Canada.
J Biomed Mater Res A. 2011 Jul;98(1):40-52. doi: 10.1002/jbm.a.33047. Epub 2011 Apr 26.
Alginate remains the most popular polymer used for cell encapsulation, yet its biocompatibility is inconsistent. Two commercially available alginates were compared, one with 71% guluronate (HiG), and the other with 44% (IntG). Both alginates were purified, and their purities were verified. After 2 days in the peritoneal cavity of C57BL/6J mice, barium (Ba)-gel and calcium (Ca)-gel beads of IntG alginate were clean, while host cells were adhered to beads of HiG alginate. IntG gel beads, however, showed fragmentation in vivo while HiG gel beads stayed firm. The physicochemical properties of the sodium alginates and their gels were thoroughly characterized. The intrinsic viscosity of IntG alginate was 2.5-fold higher than that of HiG alginate, suggesting a greater molecular mass. X-ray photoelectron spectroscopy indicated that both alginates were similar in elemental composition, including low levels of counterions in all gels. The wettabilities of the alginates and gels were also identical, as measured by contact angles of water on dry films. Ba-gel beads of HiG alginate resisted swelling and degradation when immersed in water, much more than the other gel beads. These results suggest that the main factors contributing to the biocompatibility of gels of purified alginate are the mannuronate/guluronate content and/or intrinsic viscosity.
藻酸盐仍然是用于细胞封装的最受欢迎的聚合物，但它的生物相容性不一致。比较了两种市售的藻酸盐，一种是 71%的古洛糖醛酸（HiG），另一种是 44%的甘露糖醛酸（IntG）。两种藻酸盐均经过纯化，并验证了其纯度。在 C57BL/6J 小鼠的腹腔中放置 2 天后，IntG 藻酸盐的钡（Ba）-凝胶和钙（Ca）-凝胶珠干净，而宿主细胞附着在 HiG 藻酸盐珠上。然而，IntG 凝胶珠在体内发生了碎片，而 HiG 凝胶珠保持坚固。彻底表征了两种藻酸钠及其凝胶的物理化学性质。IntG 藻酸盐的特性粘度是 HiG 藻酸盐的 2.5 倍，表明其分子量更大。X 射线光电子能谱表明，两种藻酸盐的元素组成相似，所有凝胶中的反离子含量都很低。通过测量干燥膜上水的接触角，还发现藻酸盐和凝胶的润湿性相同。当浸入水中时，HiG 藻酸盐的 Ba-凝胶珠的膨胀和降解阻力比其他凝胶珠大得多。这些结果表明，影响纯化藻酸盐凝胶生物相容性的主要因素是甘露糖醛酸/古洛糖醛酸含量和/或特性粘度。
