Lubricating Effects of Cocoa Butter and Coconut Oil in Conventional Paracetamol Tablets

Abstract

Background: Due to chemical instability of some Active Pharmaceutical Ingredients often caused by magnesium stearate and its impurities, it is expedient to research into some other materials especially of natural origin, which would probably exhibit better lubricating activity, chemically inactive, less bioactive and less prohibitive.
Objective: This work is designed to examine the lubricating properties of cocoa butter and coconut oil as alternative lubricants in comparison with conventional lubricant - magnesium stearate at different concentrations in paracetamol tablets.
Materials and Methods: Cocoa butter was extracted from the seeds of Theobroma cacao and coconut oil from the meat of matured coconuts harvested from the coconuts palm (Cocos nucifera). Physicochemical evaluation was carried out on the extracted oils. Thirteen different formulations were prepared using different lubricants; magnesium stearate, cocoa butter and coconut oil at 0 – 4 %w/w concentrations. The prepared granules were evaluated for various pre-compression characteristics (bulk density, tapped density, angle of repose, Hausner’s quotient and Carr’s index) and post-compression characteristics (weight variation, friability, hardness, disintegration and dissolution times).
Discussion: Most of the values obtained from the evaluation of pre- and post- compression characteristics correlate with the pharmacopoeial limits. The values of disintegration time were observed to increase as the lubricant concentration increased but no direct relationship with dissolution time. Tablet hardness values decreased while friability increased as the lubricant concentration increased for all the batches. From the study, cocoa butter and coconut oil at 2 – 4 % exhibited effective lubricating effect in the formulation of paracetamol tablet with respect to their values of weight variation, friability, hardness, disintegration and dissolution times.
Conclusion: Cocoa butter and coconut oil could be employed as good alternative lubricants to the conventional ones in pharmaceutical tablet formulation.

Keywords: Lubricants, Cocoa butter, Coconut oil, Magnesium stearate.