Preparation of Trimethyl Chitosan Nanoparticles and Characterization of the Entrapped Yam Dioscorin Proteins

• Main Authors: Lung-Ling Hsieh, 謝鴻伶
• Other Authors: Kuo-Chih Lin
• Format: Others
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/46136225530910842033

碩士 === 國立東華大學 === 生命科學系 === 104 === Yam storage proteins Dioscorin have been confirmed to exhibit immunomodulatory effect and alleviate allergic reaction. To improve the efficacy for absorption of Dioscorin in the intestine by oral administration and prevent poor gastrointestinal permeability and degradation by gastric acid and digestive enzyme in gastrointestinal tract, we aimed to prepare recombinant Dioscorin (rDio) coated with trimethyl chitosan (TMC) ionic cross-linking with tripolyphosphate (TPP), resulting in the formation of TMC-rDio-TPP nanoparticles (NPs). TMC synthesized from CS can attach to the intestinal mucosa and open the tight junction between epithelial cells, so that the Dioscorin released from the TMC-rDio-TPP NPs can be transported across the epithelial cells of intestine with the assistance of TMC and go into the bloodstream through paracellular pathway to achieve therapeutic effect. The physicochemical properties, pharmacokinetics and biological activity of the TMC-rDio-TPP NPs were detected. The NPs prepared from the TMC : rDio : TPP mass ratio of 4 : 2 : 1 had the smallest particle size and appropriate Zeta potential. The loading capacity and entrapment efficiency of Dioscorin in the TMC-rDio-TPP NPs were more than 25% and 60%, respectively. More than 60% of rDioscorin were released after incubated in pH 7.4 buffer for 1 h. The Dioscorin released from the TMC-rDio-TPP NPs exhibited bioactivity for stimulating the proliferation and phagocytosis effect of macrophage RAW264.7 and activatting the gene expression of IL-1 and IL-6. Furthermore, incubation of the TMC-rDio-TPP NPs in the Caco-2 cell monolayer in PBS buffer (pH 7.4) for 2 h led to the increase of Papp to 4.4-5.6 folds, suggesting that Dioscorin can be promptly transported across the epithelial cells of intestine with the assistance of TMC and go into the bloodstream through paracellular pathway to achieve therapeutic effect.