Background: The solubility/dissolution of a drug in the gastrointestinal (GI) region and the
permeability of a drug through the GI membrane are the two key parameters governing drug absorption.
Poor aqueous solubility is the rate-limiting factor for the absorption of poorly soluble drugs
through the GI region.
Objective: The purpose of this work is to investigate the influence of two different hydrotropes, namely
sodium benzoate (SB), and nicotinamide (NA), at different levels (10-40%) and in combination on the
solubility and permeability of poorly soluble drug glibenclamide (GLB). The work will find out,
whether the solubility enhancement of glibenclamide using hydrotropes and hydrotropic blends also affects
the GI permeability of glibenclamide.
Methods: A 32 full factorial design was employed to study the influence of hydrotropic blends of sodium
benzoate and nicotinamide on the solubility and permeability of GLB. The solubility and permeability
of drugs at different levels (10-40%) of hydrotropes (SB, NA) and their blends are determined
using a magnetic stirrer and in vitro Franz diffusion cell, respectively.
Results: The results of preliminary studies revealed an increase in the solubility and reduction in the
apparent permeability of GLB as a function of increasing levels of both hydrotropes.
Conclusion: In this work, it was found that an increase in solubility with hydrotropes results in a decrease
in permeability of GLB. The solubility enhancement and the permeability decrease were observed
more in hydrotropic blends in comparison to individual hydrotropes. Therefore, it is concluded
that both factors, solubility and permeability, must be optimized to achieve appreciable gains in