Here we discuss how the position of carboxyalkyl substitute and the type of the cross-linking agent affect properties of chitosan-based metal-affine sorbents. Using fluoroquinolone (ciprofloxacin) as a model compound we have shown that metal-chelates of N- and N,O-carboxyalkyl chitosan derivatives cross-linked with hexamethylene diisocyanate and epichlorohydrin differ in sorption properties. Despite high (>90%) efficacy of ciprofloxacin recovery by Cu(II)- and Al(III)-chelates of N- and N,O-carboxyalkylchitosans from water, the latter were much sensitive to the increase of ionic strength and the presence of Ca²⁺ ions. The difference in the structure of Cu(II) complexes depending on the type of carboxyalkyl substitution was revealed by electron spin resonance (ESR) spectroscopy. Analysis of the metal ions release during ciprofloxacin sorption have shown that Cu(II)- and Al(III)-chelates of N,O-carboxyalkylchitosan were less stable and less efficient as metal-affine sorbents for ciprofloxacin than N-regioselectively substituted carboxyethylchitosan, which showed properties comparable to those of Cu(II)-chelates of commercial imido-diacetic acid (IDA)-agarose.

在这里，我们讨论了羧烷基取代基的位置和交联剂的类型如何影响基于壳聚糖的金属仿射吸附剂的性能。使用氟喹诺酮（环丙沙星）作为模型化合物，我们已经表明，与六亚甲基二异氰酸酯和表氯醇交联的N-和N，O-羧烷基壳聚糖衍生物的金属螯合物的吸附性能不同。尽管铜（II）和铝（III）螯合物从水中回收N-和N，O-羧基烷基壳聚糖的环丙沙星的回收效率高（> 90％），但后者对离子强度的增加和存在非常敏感钙²⁺离子。通过电子自旋共振（ESR）光谱揭示了取决于羧基烷基取代类型的Cu（II）配合物的结构差异。对环丙沙星吸附过程中释放的金属离子的分析表明，N，O-羧烷基壳聚糖的Cu（II）和Al（III）螯合物作为环丙沙星的金属亲和吸附剂比N-区域选择性取代的羧乙基壳聚糖不稳定，效率低。其显示的性质与市售的亚氨基二乙酸（IDA）-琼脂糖的铜（II）螯合物相当。