Functional characterisation of powders consisting of mixtures of glyceryl behenate and a non-ionic surfactant applied by hot-melt coating: lubricant performance

Solid-phase lubricants are routinely used in tablet manufacturing to reduce friction during the densification and ejection phases. However, two main challenges are commonly observed: a) poor blending of the lubricant with the other components; b) increased hydrophobicity of the mix. Hot-melt coating, wherein the substrate is coated with a composite lubricant consisting of glyceryl behenate and a non-ionic surfactant (polyethylene glycol behenate), offers a solution to these challenges. Comparative studies were undertaken using the composite lubricant in a hot-melt coating process and in a ‘standard’ physical blending method. This study shows that the addition of a surfactant to glyceryl behenate does not impair its performance as a lubricant, and that hot-melt coating favors the homogeneous distribution of the lipid excipient onto the surface of particles even when the coating mixture contains more than 50 % surfactant.