Author/Authors :
Wu, Jia-Hui Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China , Wang, Xiao-Juan Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China , Li, Shu-Juan Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China , Ying, Xiao-Ying Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China , Hu, Jing-Bo Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China , Xu, Xiao-Ling Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China , Kang, Xu-Qi Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China , You, Jian Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China , Du, Yong-Zhong Institute of Pharmaceutics - College of Pharmaceutical Sciences - Zhejiang University, Hangzhou, PR China
Abstract :
Sustained release of thermal-instable and water-soluble drugs with low molecule weight is
a challenge. In this study, sodium bicarbonate was encapsulated in ethyl cellulose microspheres
by a novel solid-in-oil-in-oil (S/O/O) emulsification method using acetonitrile/soybean oil as
new solvent pairs. Properties of the microspheres such as size, recovery rate, morphology,
drug content, and drug release behavior were evaluated to investigate the suitable preparation
techniques. In the case of that the ratio of the internal and external oil phase was 1: 9, Tween
80 as a stabilizer resulted in the highest drug content (2.68%) and a good spherical shape
of microspheres. After the ratio increased to 1: 4, the microspheres using Tween 80 as the
stabilizer also had high drug content (1.96%) and exhibited a sustained release behavior,
with 70% of drug released within 12 h and a sustained release of more than 40 h. Otherwise,
different emulsification temperatures at which acetonitrile was evaporated could influence the
drug release behaviour of microspheres obtained. This novel method is a potential and effective
method to achieve the encapsulation and the sustained release of thermal-instable and watersoluble
drugs with low molecule weight.
Keywords :
Microspheres , Sodium bicarbonate , Sustained release , Stabilizer , Encapsulation
