Binding and leakage of barium in alginate microbeads
Binding and leakage of barium in alginate microbeads
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DOI：
10.1002/jbm.a.34237
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发表时间：
2012-11-01
影响因子：
4.9
通讯作者：
Strand, Berit L.
中科院分区：
文献类型：
--
作者：
Morch, Yrr A.;Qi, Meirigeng;Strand, Berit L.
与 Ca2+ 和/或 Ba2+ 交联的海藻酸盐微珠是细胞治疗中常用的基质。本研究的目的是量化藻酸盐微珠中钡的结合及其在体外的渗漏和体内条件下的积累。将胶凝溶液中的低浓度钡 (1 mM) 与钙 (50 mM) 和高浓度钡 (20 mM) 组合用于制备由高 G 和高 M 海藻酸盐制成的微珠。与在所有胶凝条件下仅暴露于钙和高 M 微珠的高 G 微珠相比，高 G 微珠从胶凝溶液中积累了钡，并且在低和高 Ba 暴露下都含有更高浓度的二价离子。尽管大多数未结合的二价离子在洗涤和培养步骤中被去除，但在储存过程中仍然检测到钡的泄漏。发现植入高 G 珠的小鼠血液和股骨中的钡积累具有剂量依赖性。与藻酸盐微珠胰岛移植到糖尿病患者相关的估计的钡泄漏表明，泄漏比世界卫生组织给出的使用低浓度钡制成的高 G 微珠的耐受摄入值低 2.5 倍。类似的估计结果比使用高浓度钡制成的高 G 微珠的容许摄入量高出 1.5 倍。为了降低可能引起安全问题的钡积累风险，建议使用由钙和低浓度钡离子组合胶凝的高 G 海藻酸盐制成的微珠进行胰岛移植。 (c) 2012 年 Wiley periodicals, Inc. J Biomed Mater Res Part A：100A：29392947，2012 年。
Microbeads of alginate crosslinked with Ca2+ and/or Ba2+ are popular matrices in cell-based therapy. The aim of this study was to quantify the binding of barium in alginate microbeads and its leakage under in vitro and accumulation under in vivo conditions. Low concentrations of barium (1 mM) in combination with calcium (50 mM) and high concentrations of barium (20 mM) in gelling solutions were used for preparation of microbeads made of high-G and high-M alginates. High-G microbeads accumulated barium from gelling solution and contained higher concentrations of divalent ions for both low- and high-Ba exposure compared with high-G microbeads exposed to calcium solely and to high-M microbeads for all gelling conditions. Although most of the unbound divalent ions were removed during the wash and culture steps, leakage of barium was still detected during storage. Barium accumulation in blood and femur bone of mice implanted with high-G beads was found to be dose-dependent. Estimated barium leakage relevant to transplantation to diabetic patients with islets in alginate microbeads showed that the leakage was 2.5 times lower than the tolerable intake value given by WHO for high-G microbeads made using low barium concentration. The similar estimate gave 1.5 times higher than is the tolerable intake value for the high-G microbeads made using high barium concentration. To reduce the risk of barium accumulation that may be of safety concern, the microbeads made of high-G alginate gelled with a combination of calcium and low concentration of barium ions is recommended for islet transplantation. (c) 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:29392947, 2012.