In this study, development of folic acid-loaded liposomes using a basic amino acid, histidine as a solubilizing agent for folic acid was presented, which tackled the poor solubility of this vitamin. The effect of the liposomal membrane modifiers, cholesterol and SPAN 20 on the characteristics of the final formulations was examined. Liposomes prepared from a commercially available purified soybean lecithin (Phospholipon 90G) by proliposome method were between 503 and 877 nm in average diameter, where cholesterol induced enlargement and SPAN.20 reduction of vesicles. High encapsulation efficiency of 84% and drug loading of 0.123 mg g⁻¹ were achieved, irrespective to the composition. According to AFM images, folic acid-loaded liposomes of a fraction with a nano size were flattened compared to globular empty liposomes. FTIR analysis revealed possible interactions between phospholipids and histidine, while DSC study suggested interactions between folic acid and lipids during heating. Release study done by a Franz diffusion cell showed prolonged release of folic acid from liposomes and the release rate was determined by folic acid solubility.

在这项研究中，提出了使用碱性氨基酸组氨酸作为叶酸的增溶剂开发负载叶酸的脂质体的方法，该方法解决了该维生素的不良溶解性。检查了脂质体膜修饰剂，胆固醇和SPAN 20对最终制剂特性的影响。由脂质体方法从市售纯化的大豆卵磷脂（磷脂90G）制备的脂质体的平均直径在503至877 nm之间，其中胆固醇引起囊泡增大和SPAN.20减少。封装效率高达84％，载药量为0.123 mg g ^-1无论组成如何，都可以实现。根据AFM图像，与球形空脂质体相比，纳米级级分的叶酸负载脂质体扁平化。FTIR分析表明磷脂与组氨酸之间可能存在相互作用，而DSC研究表明加热期间叶酸与脂质之间存在相互作用。Franz扩散池进行的释放研究表明，叶酸从脂质体中的释放时间延长，释放速度由叶酸溶解度决定。