Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand.
Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand.
Mater Sci Eng C Mater Biol Appl. 2019 Apr;97:23-30. doi: 10.1016/j.msec.2018.11.076. Epub 2018 Nov 30.
In this study, a drug delivery system for chemo-hyperthermia applications is proposed and fabricated. The delivery system consists of magnetic-silica (MagSi) particles being encapsulated within a pH/thermo-responsive chitosan‑g‑N‑isopropylacrylamide (Chi-g-NIPAAm) polymer matrix. The as-prepared MagSi@Chi-g-NIPAAm particles exhibit superparamagnetic behavior with a saturation magnetization (Ms) of 20.14 emu/g. In addition, the MagSi@Chi-g-NIPAAm particles can act as a heat source when subject to an alternating magnetic field (AMF) and have a specific absorptions rate (SAR) of 8.36 Wg. The release of the drug DOX from the synthesized particles is sensitive to both the pH and temperature of its environment. We have compared the drug release when the solution is externally heated up and when it is heated up by the AMF (internal heating). For external heating (when the pH/temperature is 4.0/45 °C), 83.30 ± 2.92% of the DOX were released within the first 5 h. The release of the DOX by the particles in pH 7.4 (temperature of 37 °C) was much slower (around 25.87 ± 1.30% after 25 h). The release of the DOX was much higher (under an acidic condition pH = 4.0) around 57.13 ± 2.36% within 1 h in the presence of AMF heating. The in vitro cytotoxicity tests of the of DOX-loaded MagSi@Chi-g-NIPAAm particles towards HeLa cancer cells. In general, the toxicities of the drug DOX as part of a MagSi@Chi-g-NIPAAm particles were less than those of the standalone DOX until the concentration of DOX-loaded particles reached 250 μg/mL, after which the toxicity of DOX in both forms were the same.
在这项研究中，提出并制备了一种用于化疗-热疗应用的药物输送系统。该输送系统由磁性二氧化硅（MagSi）颗粒封装在 pH/热响应壳聚糖-g-N-异丙基丙烯酰胺（Chi-g-NIPAAm）聚合物基质内组成。所制备的 MagSi@Chi-g-NIPAAm 颗粒表现出超顺磁性，饱和磁化强度（Ms）为 20.14 emu/g。此外，当 MagSi@Chi-g-NIPAAm 颗粒受到交变磁场（AMF）作用时，它们可以充当热源，具有特定吸收率（SAR）为 8.36 Wg。合成颗粒中 DOX 的释放对其环境的 pH 值和温度均敏感。我们比较了外部加热和 AMF 加热（内部加热）时的药物释放情况。对于外部加热（当 pH/温度为 4.0/45°C 时），在最初的 5 小时内，83.30±2.92%的 DOX 被释放。在 pH 值为 7.4（温度为 37°C）的情况下，DOX 从颗粒中的释放速度较慢（25 小时后约为 25.87±1.30%）。在 AMF 加热的存在下，在酸性条件下（pH=4.0），DOX 的释放速度更高，在 1 小时内约为 57.13±2.36%。载有 DOX 的 MagSi@Chi-g-NIPAAm 颗粒对 HeLa 癌细胞的体外细胞毒性测试。一般来说，作为 MagSi@Chi-g-NIPAAm 颗粒一部分的 DOX 的毒性低于单独的 DOX，直到载有 DOX 的颗粒浓度达到 250μg/mL，此后两种形式的 DOX 的毒性相同。
