Yin Lichen, Ding Jieying, He Chunbai, Cui Liming, Tang Cui, Yin Chunhua
State Key Laboratory of Genetic Engineering, Department of Pharmaceutical Sciences, School of Life Sciences, Fudan University, 220 Handan Road, Shanghai 200433, China.
Biomaterials. 2009 Oct;30(29):5691-700. doi: 10.1016/j.biomaterials.2009.06.055. Epub 2009 Jul 16.
Trimethyl chitosan-cysteine conjugate (TMC-Cys) was synthesized in an attempt to combine the mucoadhesion and the permeation enhancing effects of TMC and thiolated polymers related to different mechanisms for oral absorption. TMC-Cys with various molecular weights (30, 200, and 500 kDa) and quaternization degrees (15 and 30%) was allowed to form polyelectrolyte nanoparticles with insulin through self-assembly, which demonstrated particle size of 100-200 nm, zeta potential of +12 to +18 mV, and high encapsulation efficiency. TMC-Cys/insulin nanoparticles (TMC-Cys NP) showed a 2.1-4.7-fold increase in mucoadhesion compared to TMC/insulin nanoparticles (TMC NP), which might be partly attributed to disulfide formation between TMC-Cys and mucin as evidenced by DSC measurement. Compared to insulin solution and TMC NP, TMC-Cys NP induced increased insulin transport through rat intestine by 3.3-11.7 and 1.7-2.6 folds, promoted Caco-2 cell internalization by 7.5-12.7 and 1.7-3.0 folds, and augmented uptake in Peyer's patches by 14.7-20.9 and 1.7-5.0 folds, respectively. Such results were further confirmed by in vivo experiment with the optimal TMC-Cys NP. Biocompatibility assessment revealed lack of toxicity of TMC-Cys NP. Therefore, self-assembled nanoparticles between TMC-Cys and protein drugs could be an effective and safe oral delivery system.
合成了三甲基壳聚糖 - 半胱氨酸共轭物（TMC - Cys），旨在结合TMC的粘膜粘附作用和与口服吸收不同机制相关的硫醇化聚合物的渗透增强作用。使具有不同分子量（30、200和500 kDa）和季铵化程度（15%和30%）的TMC - Cys通过自组装与胰岛素形成聚电解质纳米颗粒，这些纳米颗粒的粒径为100 - 200 nm，zeta电位为 +12至 +18 mV，且具有高包封率。与TMC/胰岛素纳米颗粒（TMC NP）相比，TMC - Cys/胰岛素纳米颗粒（TMC - Cys NP）的粘膜粘附性增加了2.1 - 4.7倍，这可能部分归因于TMC - Cys与粘蛋白之间形成了二硫键，差示扫描量热法测量证明了这一点。与胰岛素溶液和TMC NP相比，TMC - Cys NP使胰岛素通过大鼠肠道的转运分别增加了3.3 - 11.7倍和1.7 - 2.6倍，促进Caco - 2细胞内化分别增加了7.5 - 12.7倍和1.7 - 3.0倍，并使派尔集合淋巴结中的摄取分别增加了14.7 - 20.9倍和1.7 - 5.0倍。用最佳的TMC - Cys NP进行的体内实验进一步证实了这些结果。生物相容性评估表明TMC - Cys NP没有毒性。因此，TMC - Cys与蛋白质药物之间自组装的纳米颗粒可能是一种有效且安全的口服给药系统。
