二氧化钛纳米管作为肿瘤药物载体系统的体外负载及释放

Loading and Release of Titanium Dioxide Nanotubes as Cancer Drug Delivery System

利用表面吸附作用,将抗癌药物阿霉素(doxorubicin,DOX)负载到二氧化钛纳米管(titanium dioxide nanotubes,TiO_2-NTs)上,并进行体外药物缓释实验.通过研究DOX的质量浓度以及负载时间等因素对TiO_2-NTs的负载率和包封率的影响,得出DOX的最佳负载质量浓度为0.7 mg/mL,最佳负载时间为24 h.TiO_2-NTs对DOX的载药率为40%,包封率为75%左右.负载在TiO_2-NTs上的DOX,释放速率对pH值敏感.在pH=7的中性条件下,DOX基本不释放;在pH=3的酸性条件下,DOX随着时间的变化缓慢释放,最终的总释放率可达75%以上.

The anticancer drug, doxorubicin （DOX）, is easily loaded on titanium dioxide nanotubes （TiO2-NTs） through adsorption forces because of its high specific surface area and perfect surface activity. By studying the effects of loading conditions （concentration of DOX and loading time ） on the loaded rates and encapsulation efficiency of TiO2-NTs, the following optimum conditions were obtained： concentration of DOX is 0.7 mg/mL, and loading time is 24 h. Under these conditions, loading rates of DOX on TiO2-NTs were 40% and encapsulation efficiency was 75%. We found that the release rate of DOX loaded on TiO2-NTs was pH sensitive. We can control the release rate by adjusting pH value of the solution. Under the neutral conditions （pH = 7）, DOX loaded on TiO2-NTs releases almost nothing. When the pH value was 3, DOX released slowly over time and the release rate was up to 75%.