Development of Sustained-Release Container and High-performance Adsorbent of Pesticide Using Chitosan

壳聚糖是甲壳类动物、昆虫和植物细胞壁的基本成分，是甲壳素的一种水解衍生物，我们利用不同的交联剂戊二醛和环氧氯丙烷制备了两种类型的壳聚糖微颗粒（CMs）和膜，以及与Ag(I)和某些铂族金属离子（SCMs）络合的壳聚糖微颗粒。利用这些微粒和膜，我们研究并比较了典型农药甲基对硫磷（MP）的吸收和释放行为。研究结果如下：(1)利用壳聚糖膜和dolsa -壳聚糖杂化膜，研究了抗肿瘤药物铂族金属的渗透和缓释机制。(2)从对Ag (I)和MP吸附的pH和浓度依赖性来看，环氧氯丙烷交联CM对Ag (I)的吸附明显优于戊二醛交联CM，但对NIP在SCM上的吸附行为却相反。(3)通过低pH的醋酸和醋酸钠缓冲溶液以及含有络合试剂的缓冲溶液，观察了甲基对硫磷负载的SCMs中MP的释放行为。结果表明，含硫氰化铵（NH_4SCN）和氨（NH_40H）的水溶液可用于载MP的SCMs中MP的释放，而不会造成颗粒中银的泄漏。(4)通过柱装SCMs考察了NIP的吸附和洗脱行为，阐明了水溶液pH、NIP浓度和SCMs上Ag (I)的上载量对MP的最大上载量和吸附和洗脱率的影响。我们发现戊二醛交联SCM具有高的重复柱操作持久性，对MP具有可逆的吸附和洗脱作用。

Using Chitosan being a hydrolyzed derivative of chitin distributed in nature as a fundamental component of shells of crustaceans and insects and plant cell walls, we prepared two types of chitosan microparticles (CMs)and membranes and CMs complexed with Ag(I) and some platinum group metal ion (SCMs) using different crosslinking agents, i.e., glutaraldehyde and epichlorohydrin. Using these microparticles and membranes we ave investigated and compared the absorption and release behavior of a typical pesticide, methyl parathion (MP).The obtained results are as follows :(1) Using chitosan membrane and DOLSA-chitosan hybrid membranes, we investigated the permeation and sustained-release mechanism of platinum group metal which is the anti-tumor drug.(2) From the pH and concentration dependencies of Ag (I) and MP adsorption onto both the CMs and SCMs, the epichlorohydrin-crosslinked CM apparently showed the superiority of Ag (I) adsorption over the glutaraldehyde-crosslinked CM, nevertheless, adsorption behavior of NIP onto SCM derived from each CM were observed in reverse.(3) Release behavior of MP from the methyl parathion-loaded SCMs were also observed by aqueous buffer solutions of acetic acid and sodium acetate of low pH as well as by that containing some complexing reagents. The results suggested that the aqueous solutions containing ammonium thiocyanide (NH_4SCN) and ammonia (NH_40H) could be applied for MP release from the MP-loaded SCMs without the silver leackage from the particles.(4) We investigated the adsorption and elusion behaviors of NIP through the column packed SCMs, to elucidate the influences of pH of aqueous solution, NIP concentration and loading amount of Ag (I) on SCMs on maximal loading amount and adsorption and elusion rates of MP We have found that SCM crosslinked by glutaraldehyde has high durability of repeating column operation with reversible adsorption and elusion of MP.