pH响应改性木质素纳米粒子的制备及释药性能

以酶解木质素（EHL）和N-乙烯基吡咯烷酮（NVP）为主要原料，通过自由基聚合和自组装得到了直径约为50 nm的pH响应性马来酰化木质素-g-聚乙烯吡咯烷酮（MEHL-g-PVP）纳米粒子。考察了化学修饰、聚合物浓度、水滴加速度、搅拌速度、初始水含量和投药量对纳米粒子的形貌、尺寸和载药性能的影响。结果表明，纳米粒子的最大药物负载量可达到35.1%，包封率为64.3%。体外药物释放表明，MEHL-g-PVP具有明显的pH响应能力，在模拟人体内肠道环境和胃液中，布洛芬（IBU）的72h释放量分别为11.1%和63.75%。体外细胞毒性实验结果表明，MEHL-g-PVP载药纳米粒子对正常细胞无细胞毒性，而对结肠癌细胞的具有很好地抑制作用。MEHL-g-PVP纳米粒子有望成为口服药物的理想载体材料。

Preparation and drug release properties of pH-responsive modified lignin nanoparticles

pH responsive maleylated lignin-g-polyvinylpyrrolidone (MEHL-g-PVP) nanoparticles with a diameter of about 50 nm were synthesized by free radical polymerization and self-assembly using enzymatic lignin (EHL) and N-vinylpyrrolidone (NVP) as raw materials. The effects of chemical modification, polymer concentration, water addition rate, stirring speed, initial water content and drug dosage on the morphology, size and drug-carrying properties of nanoparticles were investigated. The results showed that the maximum drug loading of nanoparticles could reach 35.1% and the encapsulation efficiency was 64.3%. In vitro drug release showed that MEHL-g-PVP had obvious pH response ability, and the release amount of ibuprofen (IBU) was 11.1% and 63.75% in 72h in simulated intestinal environment and gastric juice of human body, respectively. The results of in vitro cytotoxicity test showed that MEHL-g-PVP drug-loaded nanoparticles had no cytotoxicity to normal cells and had a good inhibitory effect on colon cancer cells. MEHL-g-PVP nanoparticles are expected to become an ideal carrier material for oral drugs.