The Nano-encapsulation of Vitamin C by Chitosan

• Main Authors: Hsiao-wan Wen, 溫筱宛
• Other Authors: Chang-chin Kwan
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/00290622349670191866

碩士 === 靜宜大學 === 應用化學研究所 === 95 === Abstract The purpose of this study is attempted to prepare nano-encapsule by using chitosan and glutaraldehyde. Chitosan is a class of biodegradable and biocompatible polymers which has been considered as a good candidate for the studies of drug loading and releasing properties. The stable nano-encapsules may be obtained from the micro-emulsion process, and change oil phase, surfactant concentration with the suitable phase inversion temperature. The phase temperature is control 40℃ and employ it preparation for stable nano-encapsules. Magnesium ascorbyl phosphate is commonly used in the productions of whitening and anti-aging materials. It can prevent from the activation of tyrosine and reduce the oxidized melanin. However, Magnesium ascorbyl phosphate, a hydrophilic derivative of ascorbic acid, is not stable in the air. In this study, magnesium ascorbyl phosphate was encapsulated in nano-particles of chitosan polymers and the effects of particle size, in vitro drug releasing in vitro and encapsulation efficiencies were also investigated. The results demonstrated that the chitosan average molecular weight is 56,800 after hydrolysis. The nano-particles shows the SEM image of a large aggregate formed of low molecular weight chitosan after hydrolysis and the nano-particles have a size range between 200-400 nm. Compared with chitosan before hydrolysis to prepare nano-particles, it shows ragged surface and the particle size greater than 1 m. The effect of different size distribution on nano-particles that by change initial concentration of cross-link agent, pH value of chitosan solutions and mass ratio of chitosan to glutaraldehyde. The nano-particles formed at solution pH 5.5, concentration of cross-link agent of 5.0% had a smaller size and better dispersion. The nano-particles of magnesium ascorbyl phosphate showed the slow releasing property in vitro. The loading capacity is 30.6% of magnesium ascorbyl phosphate.