刺激响应型控释系统在提高农药生物利用度和减少环境污染方面受到了广泛的关注。在这里,以改性羧甲基β-环糊精(CβCD-ss-COOH)为密封材料,构建了多刺激响应型IMI@HCuS@mSiO2@-ss-CβCD传递系统,以氨基功能化介孔二氧化硅壳(HCuS@mSiO2-NH2)为载体,以吡虫啉(IMI)为模型药物。HCuS@mSiO2-NH2的空腔结构将为农药装载提供很大的空间。结果表明,HCuS@mSiO2-ss-CβCD的大小约为230nm,IMI的负载效率为25.7%,并对细菌和种子表现出更好的生物安全性。HCuS载体还用作光热剂,具有较高的光热转化效应(η=38.4%)。IMI@HCuS@mSiO2@-ss-CβCD表现出优异的叶子粘附性和对pH的多种刺激响应释放特性,α-淀粉酶,GSH,和NIR。嵌入CuS@mSiO2@-ss-CβCD中的IMI的光稳定性约为IMI溶液的10倍。这项工作为实现农药输送提供了一个有效的纳米平台。
Stimuli-responsive controlled release systems have received extensive attention to improve the pesticide bioavailability and minimize environmental pollution. Herein, a multiple stimuli-responsive IMI@HCuS@mSiO2 @ -ss-CβCD delivery system was constructed using modified carboxymethyl β-cyclodextrin (CβCD-ss-COOH) as sealing materials, hollow copper sulfide nanoparticles with amino-functionalized mesoporous silica shell (HCuS@mSiO2-NH2) as carriers and imidacloprid (IMI) as the model drug. The cavity structure of HCuS@mSiO2-NH2 would provide a large space for pesticide loading. The results revealed that HCuS@mSiO2-ss-CβCD was approximately 230 nm in size and the loading efficiency for IMI was 25.7%, and exhibited better biosafety on bacteria and seed. HCuS carriers were also served as photothermal agent and possessed high photothermal conversion effect (η = 38.4%). IMI@HCuS@mSiO2 @ -ss-CβCD displayed excellent foliage adhesion and multiple stimuli-responsive release properties to pH, α-amylase, GSH, and NIR. The photostability of IMI embedded in CuS@mSiO2 @ -ss-CβCD was approximately 10 times that of IMI solution. This work provides an efficient nanoplatform for realizing pesticide delivery.