Kanth Vanarchi Rajini, Kajjari Praveen B, Madalageri Priya M, Ravindra Sakey, Manjeshwar Lata S, Aminabhavi Tejraj M
Department of Physics, College of science, engineering And Technology, University of South Africa, Pretoria 1709, South Africa.
Department of Chemistry, Karnatak University, Dharwad 580 003, India.
Pharmaceutics. 2017 Mar 27;9(2):13. doi: 10.3390/pharmaceutics9020013.
Carboxymethyl chitosan (CMCS) was synthesized and blended with gelatin (GE) to prepare hydrogel microspheres by w/o emulsion cross-linking in the presence of glutaraldehyde (GA), which acted as a cross-linker. 5-Fluorouracil (5-FU) was encapsulated to investigate its controlled release (CR) characteristics in acidic (pH 1.2) and alkaline (pH 7.4) buffer media. The microspheres which formed were spherical in nature, with smooth surfaces, as judged by the scanning electron microscopy (SEM). Fourier transform infrared spectroscopy (FTIR) confirmed the carboxymethylation of CS and the chemical stability of 5-FU in the formulations. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) confirmed the physical state and molecular level dispersion of 5-FU. Equilibrium swelling of microspheres was performed in water, in order to understand the water uptake properties. The in vitro release of 5-FU was extended up to 12 h in pH 7.4 phosphate buffer, revealing an encapsulation efficiency of 72%. The effects of blend composition, the extent of cross-linking, and initial drug loading on the in vitro release properties, were investigated. When analyzed through empirical equations, the release data suggested a non-Fickian transport mechanism.
合成了羧甲基壳聚糖（CMCS），并将其与明胶（GE）混合，在作为交联剂的戊二醛（GA）存在下，通过油包水乳液交联法制备水凝胶微球。将5-氟尿嘧啶（5-FU）包封在微球中，以研究其在酸性（pH 1.2）和碱性（pH 7.4）缓冲介质中的控释（CR）特性。通过扫描电子显微镜（SEM）判断，形成的微球呈球形，表面光滑。傅里叶变换红外光谱（FTIR）证实了壳聚糖的羧甲基化以及制剂中5-FU的化学稳定性。差示扫描量热法（DSC）和X射线衍射（XRD）证实了5-FU的物理状态和分子水平的分散情况。在水中进行微球的平衡溶胀实验，以了解其吸水性能。在pH 7.4的磷酸盐缓冲液中，5-FU的体外释放时间延长至12小时，包封率为72%。研究了共混物组成、交联程度和初始载药量对体外释放性能的影响。通过经验方程分析时，释放数据表明其释放机制为非菲克扩散。
