Transportation of AIE-visualized nanoliposomes is dominated by the protein corona

Liposomes, especially cationic liposomes, are the most common and well-investigated nanocarriers for biomedical applications, such as drug and gene delivery. Like other types of nanomaterials, once liposomes are incubated in a biological milieu, their surface can be immediately cloaked by biological components to form a protein corona, which confers a new ‘biological identity’ and modulates downstream interactions with cells. However, it remains unclear how the protein corona affects the transportation mechanism after liposomes interact with cells. Here, we employed home-made aggregation-induced-emission-visualized nanoliposomes TR4@Lipo as a model to investigate transportation with or without the protein corona by optical imaging techniques. The results show that the protein corona can change the cellular transportation mechanism of TR4@Lipo from energy-independent membrane fusion to energy-dependent endocytosis. The protein corona also modulates the intracellular distribution of loaded cargoes. This knowledge furthers our understanding of bio-nano interactions and is important for the efficient use of cationic liposomes.     

Docetaxel-loaded liposomes: preparation, pH sensitivity, Pharmacokinetics, and tissue distribution

Docetaxel (DTX), as a member of taxoid family, has been widely used in the treatment of cancers. The present study prepared pH-sensitive DTX-loaded liposomes (DTX-Lips) by thin-film dispersion method and various physico-chemical and morphological properties were examined. The pH sensitivity of in vitro DTX release and the in vivo pharmacokinetics and tissue distribution using Kunming mice were also investigated. The mean particle size and zeta potential of DTX liposomes were (277±2) nm and (−32.60±0.26) mV, respectively. Additionally, in vitro drug release study showed that the cumulative release rate was 1.3 times more at pH 5.0 than at pH 7.4, suggesting a pH-dependent release ability of DTX-Lips. Pharmacokinetic and pharmaceutical studies in comparison with Duopafei® showed that the half-time period (t _1/2) and area under the curve (AUC) of DTX-Lips in mouse plasma were 1.8 times longer and 2.6 times higher, respectively, and that DTX-Lips selectively accumulated in macrophage-rich organs such as liver and spleen. These results together suggest that the DTX-Lips could be a promising formulation for the clinical administration of DTX.     

黄芩素脂质体包封率的测定

用逆相蒸发法制备黄芩素脂质体,4000r/min,离心10min,分离含药脂质体和游离的药物,稀释后测定其上清和沉淀吸光度,计算其浓度。由包封率=(总浓度一沉淀浓度)/总浓度X 100%计算包封率。发现溶液的稳定性和精密度都良好,测得脂质体中药物的包封率分别为38.49%,36.64%,39.55%,结果较为接近。说明低速离心法是一种有效的水不溶性药物脂质体包封率的测定方法。     

离心法测定隐丹参酮脂质体包封率

以隐丹参酮作为模型药,制备隐丹参酮納米脂质体,验证了采用离心法测定隐丹参酮納米脂质体的包封率方法的可行性。     

冷冻干燥法制备隐丹参酮纳米脂质体

目的：用大豆卵磷脂作为载体,以隐丹参酮作为模型药。制备隐丹参酮纳米脂质体。方法：用超声一匀浆一冷冻干燥法制备隐丹参酮纳米脂质体。采用透射电镜测试隐丹参酮脂质体的粒径,用激光粒度分布仪测试平均粒径及粒度分布。结果：冷冻干燥法制备隐丹参酮纳米脂质体的粒径20—80nm之间。随着大豆卵磷脂与隐丹参酮配比的减小,粒径逐渐减小,包封率逐渐减小。体外释药表现为零级动力学释药特征。结论：用超声一匀浆一冷冻干燥法制备隐丹参酮纳米脂质体的方法可行。     

制备丹参酮ⅡA脂质体的方法比较

用大豆卵磷脂作为载体,以丹参酮ⅡA作为模型药.分别采用冻融法、逆相蒸发法、超声-匀浆-冷冻干燥法制备丹参酮ⅡA纳米脂质体.采用透射电镜测试脂质体的粒径,用激光粒度分布仪测试平均粒径及粒度分布.结论:用超声-匀浆-冷冻干燥法制备丹参酮ⅡA纳米脂质体的方法简易可行.