Development of Water-Insoluble Quaternary Ammonium Salt of Chitosan Nanofibrous Membrane and Its Antibacterial Application

• Main Authors: WU,JHENG-YU, 吳政諭
• Other Authors: CHANG,YU-KUANG
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/97ueku

碩士 === 明志科技大學 === 化學工程系生化工程碩士班 === 106 === In this study, the positively charged chitosan nanofiber membrane was prepared by electrospinning technology. The negatively charged bacterial cells can be adsorbed by the positively charged chitosan to prevent the growth and reproduction of the bacteria and achieve the antibacterial activity. However, the antibacterial activity of chitosan may be effective under the acidic conditions; hence the applications of chitosan in the antibacterial fields is limited. To make the chitosan carry a permanent positive charge, Glycidyl-trimethylammonium chloride (namely, GTMAC) was used for chemically grafting with chitosan at temperature of 80 ℃ for 24 hr. The obtained product is N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride (namely, HTCC) and is a water-soluble material; hence, it cannot be directly employed in the electrospinning process. Therefore, biodegradable polyvinyl alcohol (namely PVA, 90-50%, w/w) and isocyanate crosslinking agent (namely, CLA 0-3%, w/w) were added into the HTCC solution (10-50%, w/w) and the mixed polymer solutions with various compositions were used as electrospinning polymer solutions. The results showed that the optimal electrospinning conditions are PVA and chitosan weight ratio 9:1, the working voltage 15 kV and the feed flow rate 1.2 mL/h and the nanofiber diameter is approximately 250 nm. Under different compositions of mixed polymer solutions, the weight ratio of PVA to chitosan and PVA to HTCC without crosslinking agent was 7:3, the antibacterial activity has a maximum value of 73.82% and 88.64%, respectively. However, for consideration of the uniformity of nanofiber membrane, the further experiments were carried out with weight ratio (9:1) of PVA to HTCC containing 2% and 3% crosslinking agent in dry and wet states. The HTCC/PVA/CLA nanofiber membrane has a higher antibacterial activity as treated with crosslinking agent at different temperatures (100-150 ℃). The antibacterial activity of HTCC/PVA/CLA nanofiber membrane in dry state was up to 99.7%. After one hour of contact with water, the weight loss of the nanofiber membrane was approximately 10%, the antibacterial activity after water immersion (1 h) was as high as 99% (3% CLA, 150℃), indicating that the HTCC (10%) /PVA (90%) /CLA (2-3% CLA, 125-150 ℃) nanofiber membrane has high potential for use in antimicrobial applications.