Microencapsulation using aqueous dispersion of lipid matrix by fluidized bed processing technique for stabilization of choline salt

Abstract

Choline bitartrate (CBT) is a water soluble essential nutrient belongs to vitamin-B family. It is moisture sensitive in nature and marketed formulation has stability related problems during storage which curtails its effectiveness. Waxes such as hydrogenated soya bean oil (HSO) reported to be an excellent coating carrier to reduce moisture sensitivity or hygroscopic nature of drug candidates. However, literature dictates HSO applications has been explored mostly using non-aqueous methods or hot melt techniques of formulation development. In this work, microparticles of choline bitartrate with aqueous coating dispersion of HSO as primary carrier was successfully developed using fluidized bed coating technique. Aqueous dispersion of HSO was prepared using selected binder in a homogenizer and formed aqueous dispersion was then sprayed through 0.8 mm gun in fluidized bed processor. The microparticles were evaluated for parameters like flow properties, morphological characteristics, drug content, encapsulation efficiency and drug release behaviour. The solid state characterization of optimized microparticle based formulation was done by differential scanning calorimetry, X-ray diffractometry, infrared spectroscopy and scanning electron microscopy. The results showed that microencapsulation of choline bitartrate were successfully done by aqueous wax coating dispersion without using any organic solvent or hot melt techniques. Discolouration, fishy odour and drug content variation was not observed after 6 months stability studies. Choice of proper carrier to drug ratio and selective formulation technique are critical parameters for dispensing CBT microparticle based formulation which might significantly enhance its effectiveness.