Vicissitudes of liquid crystals for solubility enhancement of poorly soluble drugs

A drug product should have aqueous solubility to avoid bioavailability issues. Low and erratic bioavailability is a problem encountered by almost 40-60% of new drug products coming out of research and development which are aimed to be delivered orally. This issue hampers their safety and efficacy as development of an efficacious formulation is halted in the initial stages of drug product development. A lot of techniques are available in the literature for the solubility enhancement of drug products with their set of advantages and disadvantages. Pharmaceutical nanoparticle engineering has recently come into existence with a number of approaches. One such approach is liquid crystal technology which can improve the drug solubility and therefore its dissolution and bioavailability by modifying the drug particles. This review aims to cover the classification, advantages, methods of preparation of liquid crystals and lipids used in formulation of cubic and hexagonal phases. It also discusses the potential applications and mechanisms behind the increase in drug solubility using this technique by taking examples from the literature. (C) 2020 Elsevier B.V. All rights reserved.