Subscribe to RSS
Formulation development of film coated tablets of Malvastrum coromandelianum (Linn.) Garcke spray-dried extract
Spray-dried extract of Malvastrum coromandelianum (Linn.) Garcke, (MCS), has been reported to lower blood glucose with no abnormalities from chronic toxicity study in Wistar rats [1, 2]. The extract is highly sensitive to air moisture. Therefore, this study was to prepare film coated tablets of high dose MCS by direct compression and pan coating techniques. Varying amount of lactose, microcrystalline cellulose, sodium starch glycolate, and fixed amount of lubricants and 300mg of MCS were mixed and directly compressed into tablets. The optimal tablets were then coated with different levels of hydroxypropylmethyl cellulose (HPMC), chitosan and polymethacrylate. The physicochemical properties of MCS and MCS tablets were evaluated. MCS particles had spherical shape with narrow particles size distribution. The aggregation of particles was responsible for poor flow properties. Adding microcrystalline cellulose and sodium starch glycolate retarded the tablet disintegration due to gel formation around the tablets. Freshly coated tablets by different polymer exhibited quite similar physicochemical properties and conformed to compendia. After storage at accelerated condition for 4 months, polymethacrylate-coated tablets still maintained the properties while HPMC- and chitosan-coated tablets swelled. The dissolution of all tablets was >80% except those coated with chitosan and stored for 4 months at accelerated condition. On conclusion, MCS coated tablets could be successfully prepared by direct compression and pan coating method. The tablets had good appearance and met the requirement of compendia.
Acknowledgement: The authors wish to thank the National Research Council of Thailand for financial support
References: 1. Jesadanont, S. et al. (2005) Thai J. Pharm. Sci. 29(suppl.):121
2. Attawish, A. et al. (1999) Bull. Dpt. Med. Sci. 40:41–54.