Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, SK S7N 5C9, Canada.
Int J Mol Sci. 2020 Sep 27;21(19):7130. doi: 10.3390/ijms21197130.
The context of this study responds to the need for sorbent technology development to address the controlled removal of inorganic sulfate (SO) from saline water and the promising potential of chitosan as a carrier system for organosulfates in pharmaceutical and nutraceutical applications. This study aims to address the controlled removal of sulfate using chitosan as a sustainable biopolymer platform, where a modular synthetic approach was used for chitosan bead preparation that displays tunable sulfate uptake. The beads were prepared via phase-inversion synthesis, followed by cross-linking with glutaraldehyde, and impregnation of Ca ions. The sulfate adsorption properties of the beads were studied at pH 5 and variable sulfate levels (50-1000 ppm), where beads with low cross-linking showed moderate sulfate uptake (35 mg/g), while cross-linked beads imbibed with Ca had greater sulfate adsorption (140 mg/g). Bead stability, adsorption properties, and the point-of-zero charge (PZC) from 6.5 to 6.8 were found to depend on the cross-linking ratio and the presence of Ca. The beads were regenerated over multiple adsorption-desorption cycles to demonstrate the favorable uptake properties and bead stability. This study contributes to the development of chitosan-based adsorbent technology via a modular materials design strategy for the controlled removal of sulfate. The results of this study are relevant to diverse pharmaceutical and nutraceutical applications that range from the controlled removal of dextran sulfate from water to the controlled release of chondroitin sulfate.
本研究的背景是为了满足从盐水中去除无机硫酸盐（SO ）的吸附剂技术发展的需要，以及壳聚糖作为药物和营养保健品中有机硫酸盐载体系统的有前途的潜力。本研究旨在利用壳聚糖作为可持续的生物聚合物平台来实现硫酸盐的控制去除，其中使用模块化合成方法来制备具有可调硫酸盐吸收能力的壳聚糖珠。通过相转化合成制备珠粒，然后用戊二醛交联，并浸渍钙离子。研究了珠粒在 pH 5 和可变硫酸盐水平（50-1000 ppm）下的硫酸盐吸附性能，低交联珠粒显示出中等的硫酸盐吸收能力（35 mg/g），而交联并浸渍钙离子的珠粒具有更大的硫酸盐吸附能力（140 mg/g）。发现珠粒的稳定性、吸附性能和零电荷点（PZC）从 6.5 到 6.8 取决于交联比和钙离子的存在。通过多次吸附-解吸循环对珠粒进行再生，以证明其良好的吸收性能和珠粒稳定性。本研究通过模块化材料设计策略为基于壳聚糖的吸附剂技术的发展做出了贡献，用于控制硫酸盐的去除。本研究的结果与从水中去除葡聚糖硫酸盐到控制硫酸软骨素释放等各种药物和营养保健品的应用相关。
