Santos Ana C, Pattekari Pravin, Jesus Sandra, Veiga Francisco, Lvov Yuri, Ribeiro António J
†Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga, Faculty of Medicine, Pólo I, First Floor, 3000-504 Coimbra, Portugal.
‡Faculty of Pharmacy, University of Coimbra, Azinhaga Sta. Comba, 3000-548 Coimbra, Portugal.
ACS Appl Mater Interfaces. 2015 Jun 10;7(22):11972-83. doi: 10.1021/acsami.5b02002. Epub 2015 May 27.
Sonication-assisted layer-by-layer (LbL) self-assembly is a nanoencapsulation technique based on the alternate adsorption of oppositely charged polyelectrolytes, enabling the encapsulation of low solubility drugs. In this work, a top-down LbL technique was performed using a washless approach and ibuprofen (IBF) as a model class II drug. For each saturated layer deposition, polyelectrolyte concentration was determined by titration curves. The first layer was constituted by cationic poly(allylamine hydrochloride) (PAH), given the IBF negative surface charge, followed by anionic polystyrenesulfonate (PSS). This polyelectrolyte sequence was made up with 2.5, 5.5, and 7.5 bilayer nanoshells. IBF nanoparticles (NPs) coated with 7.5 bilayers of PAH/PSS showed 127.5 ± 38.0 nm of particle size, a PDI of 0.24, and a high zeta potential (+32.7 ± 0.6 mV), allowing for a stable aqueous nanocolloid of the drug. IBF entrapment efficiency of 72.1 ± 5.8% was determined by HPLC quantification. In vitro MTT assay showed that LbL NPs were biocompatible. According to the number of coating layers, a controlled release of IBF from LbL NPs was achieved under simulated intestinal conditions (from 5 h up to 7 days). PAH/PSS-LbL NPs constitute a potential delivery system to improve biopharmaceutical parameters of water low solubility drugs.
超声辅助逐层（LbL）自组装是一种基于带相反电荷的聚电解质交替吸附的纳米封装技术，可实现低溶解度药物的封装。在这项工作中，采用免洗方法并以布洛芬（IBF）作为II类模型药物进行了自上而下的LbL技术研究。对于每一次饱和层沉积，通过滴定曲线确定聚电解质浓度。鉴于IBF的负表面电荷，第一层由阳离子聚（烯丙胺盐酸盐）（PAH）构成，随后是阴离子聚苯乙烯磺酸盐（PSS）。该聚电解质序列由2.5、5.5和7.5个双层纳米壳组成。涂覆有7.5个PAH/PSS双层的IBF纳米颗粒（NPs）的粒径为127.5±38.0 nm，多分散指数（PDI）为0.24，且具有较高的zeta电位（+32.7±0.6 mV），从而形成了该药物稳定的水性纳米胶体。通过高效液相色谱（HPLC）定量测定，IBF的包封率为72.1±5.8%。体外MTT试验表明LbL NPs具有生物相容性。根据包衣层数，在模拟肠道条件下（从5小时到7天）实现了IBF从LbL NPs的控释。PAH/PSS-LbL NPs构成了一种潜在的给药系统，可改善水难溶性药物的生物药剂学参数。
