Department of Chemical Engineering, University of Tulsa, 600 S. College Avenue, Tulsa, Oklahoma 74104-3189, USA.
Biotechnol Bioeng. 1997 Jan 5;53(1):41-8. doi: 10.1002/(SICI)1097-0290(19970105)53:1<41::AID-BIT7>3.0.CO;2-Z.
The stability of NAD(H) immobilized to a crosslinked agarose support (Sepharose(R)-4B) was examined in buffer solutions at a pH of 7.0 and 8.5. Specifically, this study investigated particle attrition and ligand leakage rates from a cyanogen bromide activated agarose support. Particle attrition did not occur under the experimental conditions. Ligand leakage rates were found to be first order in immobilized ligand concentration with two labile populations of ligand. The two-population model is consistent with the cyanogen bromide coupling chemistry, which results in both an isourea and imidocarbonate ligand linkage. The rate of ligand leakage was found to occur over a time scale of days, with first order rate constants ranging from 0.007 to 0.15 d(-1), depending on solution pH. (c) 1997 John Wiley & Sons, Inc.
在 pH 值为 7.0 和 8.5 的缓冲溶液中，研究了固定在交联琼脂糖载体（Sepharose（R）-4B）上的 NAD（H）的稳定性。具体而言，本研究调查了氰化溴活化琼脂糖载体的颗粒磨损和配体泄漏率。在实验条件下，未发生颗粒磨损。配体泄漏率与固定配体浓度呈一级关系，存在两种不稳定的配体。两种群模型与氰化溴偶联化学一致，这导致形成异脲和亚氨基碳酸盐配体键。配体泄漏的速率在数天的时间尺度内发生，一级速率常数范围为 0.007 至 0.15 d（-1），取决于溶液 pH 值。（c）1997 年 John Wiley & Sons，Inc.
