P 型沸石分子筛结构调控对吸附接枝二甲酸钾成缓释抗菌剂的制约

The zeolite functionality and the friendly antibiotics research, forming the slow release resist bacteria effect, is one of the domain pending solution key scientific questions. The purpose is to solve the problem that new alternative to antibiotics growth promoters Potassium diformate quick decomposition in the gastrointestinal tract and can not reach the small intestine for bacteriostasis. We used Guangxi natural zeolite as material and via open hydro-thermal method and molecular design of inorganic micro-porous crystalline materials science to prepare zeolite P; Analysis the P zeolite molecular sieve structural unit, the shape, the passageway size and the surface properties as well as the hydro-thermal; Study the P zeolite molecular sieve nature Gallic acid center, the superficial hydroxyl or the T-0-T bridge with two potassium formiate adsorption stem grafting conditions, expounded the P zeolite molecular sieve with two potassium formiate adsorption stem grafting reaction processes, analysis P the zeolite molecular sieve surface silicon OH key and so on, forms the adsorption stem grafting active carbonyl groups and bases with on two potassium formiate C=O O the union mechanism; Control the surface-bonding of zeolite and explore the surface design and surface reconstruction mechanisms of dimethyl potassium on the surface of zeolite P; Reveal the adsorption and grafting, host-guest complex inherent laws of zeolite P and dimethyl potassium;Clear in light, heat and other effects, the issues of sustained release antimicrobial bad solution antibacterial period, antibacterial mechanism and application security; These can provide approaches for the microscopic nature of antimicrobial sustained release effect.

分子筛功能性研究和友好型抗菌剂研发，形成缓释抗菌效应，是该领域有待解决的关键科学问题之一。以解决新型抗生素促生长剂替代物二甲酸钾在胃肠道分解快，无法到达小肠形成抑菌为目的。利用广西天然沸石为原料，采用开放水热法，通过无机微孔晶体材料学的分子设计定向制备P型沸石分子筛；分析P型沸石分子筛结构单元、形状、孔道尺寸和表面性质以及水热稳定性；研究P型沸石分子筛质子酸中心、表面羟基或T-0-T桥与二甲酸钾的吸附接枝条件，阐明P型沸石分子筛与二甲酸钾的吸附接枝反应过程，解析P型沸石分子筛表面硅OH键等，与二甲酸钾C=O上的O形成吸附接枝活性羰基基团的结合机理；控制沸石分子筛表面键性，探索二甲酸钾在P型沸石分子筛表面设计和表面再造机制；揭示二者吸附接枝，主客体复配化的内在规律；明确在光、热等作用下，形成的缓释抗菌剂衰解抗菌期、抗菌机理以及应用安全性等问题；为抗菌剂缓释效应的微观本质提供研究途径。

本项目关注二甲酸钾无法到达小肠，进而实现平衡肠道功能环境和控制菌落的弊端。弊端由于其在胃肠道分解快造成。制备沸石分子筛缓释抗菌剂并开展模拟抗菌试验。并借此解析缓释抗菌剂的形成过程及其控制因素，为有效提高仔猪成活率提供基础实验数据。. 天然辉沸石经酸化制成分子筛的前驱体，前驱体经碱驱形成制备分子筛的物相，制备得到A、X、P型分子筛。其中，A型为等轴晶系立方晶形，结晶度98 %，体积平均粒径4.29 μm；X型为等轴晶系八面体晶形，结晶度96 %，体积平均粒径4.98 μm；P型为四方晶系球状晶形，结晶度97 %，体积平均粒径5.26 μm。. 以P型分子筛为载体，分别采用明胶、壳聚糖为中间体，复配二甲酸钾，形成不同缓释抗菌剂；以壳聚糖+海藻酸钠为聚电解质膜，包覆分子筛与二甲酸钾复配形成的芯材，制备出微胶囊型抗菌剂。. 以明胶为中间体，反应体系中初始二甲酸钾质量浓度为40 mg/mL，P型分子筛与明胶摩尔比1:2，pH=5，常温反应3 h后形成缓释抗菌剂。酸度检测表明，抗菌剂48 h体外抗菌测试对大肠杆菌抗菌率81.35%。. 以壳聚糖为中间体时，反应体系中P型分子筛与壳聚糖与二甲酸钾质量比3:1:2，晶化温度50 ℃，水热反应3 h后形成抗菌剂。其对大肠杆菌、枯草芽孢杆菌、金黄色葡萄球菌均有抗菌效果，对金黄色葡萄球菌抗菌率87.00%，优于对大肠杆菌的抗菌率。. P型分子筛吸附二甲酸钾形成芯材。利用壳聚糖中-NH3+与海藻酸钠中-COO-发生静电吸引，形成聚电解质膜复合材料。将芯材等量、等速进入聚电解质膜的复合材料反应体系，最终形成微胶囊。. 将微胶囊加入模拟胃液环境中，一段时间后pH值几乎无变化，说明二甲酸钾没有释放。在模拟肠道环境中，溶液pH值在1-3h内由7.2下降到5.9，说明二甲酸钾有效释放。微胶囊对大肠杆菌抗菌率91.30%。. 利用天然辉沸石制备出A、X、P型结构稳定的沸石分子筛。以P型分子筛为载体，采用不同中间体复配二甲酸钾，制备出效果各异且适合仔猪食用的缓释抗菌剂。.缓释抗菌剂对金黄色葡萄球菌的抗菌率87.00%，对大肠杆菌抗菌率81-91%。本研究对提高仔猪成活率具有现实意义和科学价值。