| Cellulose is one of the most widespread and abundant polysaccharide in nature.The content of cellulose in cotton is close to 100%. But cotton cellulose can not be dissolved in water or other organic solvent, so as to limit its application. In this work,in order to improve cotton cellulose’s value in use, the cotton cellulose was degraded in to soluble oligosaccharide in 85% phosphoric acid with an assisting ultrasonic vibration. Then, the amphiphilic surfactant of oligosaccharide-poly(propylene oxide)was prepared by glycosylation between the terminal hydroxyls of soluble oligosaccharide and propylene oxide, according to addition reaction by ring-opening reaction of propylene oxide over catalyst anhydrous tin tetrachloride. Finally, the oligosaccharide-PPO surfactant was grafted on the docetaxel by ring-opening reaction of propylene oxide. This copolymer oligosaccharide-PPO-DTX could effectively improve the water-solubility of docetaxel and bring a broad application prospect in the medical field.Experiments showed that the soluble oligosaccharide(DP≈7) could be prepared successfully, while 25 g cotton cellulose was dissolved in 200 mL 85% phosphoric acid at 55 °C with tailoring reaction for duration of 10 h and acetone as precipitator.The yield of the soluble oligosaccharide was up to 36.83%. Comparison before and after tailoring reaction indicated that the chemical structure of the cotton cellulose did not change, but its crystallinity decrease from 90.6% to 41.9%. The oligosaccharide-poly(propylene oxide) surfactant had performed surface activity when the adduct numbers of propylene oxide was 20 with reacting 8h at 70 °C. The surfactant’s critical micelle concentration was 0.2mg/mL, and it’s surface tension reached 39 mN/m. While the molar ratio of docetaxel to oligosaccharide-poly(propylene oxide) surfactant was selected as 2:1 at 30 °C for grafting reaction of duration 4 h, the drug-loading rate of docetaxel reached 32.6%... |
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