[论文解读] Natural calcium carbonate for biomedical applications

Sonali S. Sali|arXiv (Cornell University)|Jun 23, 2016

Calcium Carbonate Crystallization and Inhibition参考文献 12被引用 4

一句话总结

本研究探索了从海贝壳中提取的天然碳酸钙作为可持续药物递送平台的潜力，利用其固有的孔隙率和结晶度。将海贝壳粉末处理为45–63 µm的颗粒后，实现了50%的阿司匹林和39%的雷奈酸锶包封效率，初始突释释放约80%的药物在两小时内完成，随后在19小时内持续释放。

ABSTRACT

Sea shells are found to be a very rich natural resource for calcium carbonate. Sea shells are made up of CaCO3 mainly in the aragonite form, which are columnar or fibrous or microsphere structured crystals. The bioactivity of nanoparticles of sea shell has been studied in this work. The sea shells collected were thoroughly washed, dried and pulverized. The powder was sieved and particles in the range of 45 to 63 microns were collected. The powdered sea shells were characterized using X-Ray Diffraction and Field Emission Scanning Electron Microscopy. The XRD data showed that the particles were mainly microspheres. Traces of calcite and vaterite were also present. Experiments were conducted to study the aspirin and strontium ranelate drug loading into the sea shell powder using soak and dry method. Different concentrations of drug solution was made in ethanol and water. The shell powder was soaked in drug solutions and was kept soaking for 48 hrs with intermittent ultrasonication. The mixture was gently dried in a vacuum oven. The in vitro drug release studies were done using Phosphate Buffered Saline. The FESEM images displayed a distribution of differently sized and shaped particles. The sea shells due to its natural porosity and crystallinity are expected to be useful for drug delivery. About 50% drug entrapment efficiency for aspirin and 39% for strontium ranelate was seen. A burst release of the drug (80 percent) was observed within two hours for both the drugs studied. Rest of the drug was released slowly in 19 hrs. Further modification of the sea shell with non toxic polymers is also planned as a part of this work. Sea shell powder has become a potential candidate for drug delivery due to all the aforementioned advantages.

研究动机与目标

• 评估天然海贝壳来源的碳酸钙作为生物相容性药物递送系统的潜力。
• 研究阿司匹林和雷奈酸锶在海贝壳粉末中的载药效率。
• 分析负载药物从海贝壳基质中释放的体外释放行为。
• 评估通过无毒聚合物修饰海贝壳颗粒以提升递送性能的可行性。

提出的方法

• 收集海贝壳，清洗、干燥后研磨成细粉。
• 通过筛分法分离出45–63 µm的粒径范围颗粒，以确保测试的一致性。
• 采用X射线衍射（XRD）和场发射扫描电子显微镜（FE-SEM）表征结晶度和形貌。
• 通过浸渍-干燥法进行药物负载，使用乙醇和水基药物溶液，在48小时内持续间歇超声处理。
• 采用磷酸盐缓冲液（PBS）作为释放介质，评估体外药物释放行为。
• 通过量化包封效率和释放动力学，评估性能表现。

实验结果

研究问题

• RQ1 天然海贝壳来源的碳酸钙能否作为有效且生物相容的药物递送基质？
• RQ2 阿司匹林和雷奈酸锶在海贝壳来源的碳酸钙颗粒中的载药效率如何？
• RQ3 负载药物的体外释放行为随时间如何演变？
• RQ4 海贝壳的天然孔隙率和结晶度在多大程度上影响药物释放动力学？

主要发现

• XRD分析确认主要结晶相为霰石微球，伴有少量方解石和球霰石的痕迹。
• FE-SEM图像显示不同尺寸和形状的颗粒呈现非均一分布。
• 阿司匹林的载药效率达到50%，雷奈酸锶的包封效率为39%。
• 对于阿司匹林和雷奈酸锶，初始两小时内均观察到约80%的药物突释释放。
• 剩余20%的药物在随后的19小时内逐渐释放，表明具有持续释放行为。
• 海贝壳粉末的天然孔隙率和结晶度使其成为药物递送应用中极具前景的候选材料。