Saponin Stabilized Emulsion as Sustainable Drug Delivery System: Current Status and Future Prospects

Nanopharmaceuticals play a great role in drug delivery as they increase the pharmacokinetic profile of a drug to exert a site-specific effect efficiently. In consideration of the pharmacokinetic parameters solubility of a drug is an important factor to affect the bioavailability. To overcome the solubility issues of drugs, emulsions are one of the effective drug delivery systems wherein the lipophilic and aqueous phases are mixed with the aid of surfactants and co-surfactants to obtain a homogenous system designated as micro or nanoemulsions depending upon the globule size of the dispersed phase. Most of these surfactants in use are synthetic or semi-synthetic having toxic and hazardous effects thus created the demand for safe sustainable plant-based natural surfactants. Saponins, triterpenoid glycosides, possess the characteristics of a typical surfactant by bearing both lipophilic (aliphatic terpenoids unit) and hydrophilic (attached sugars) moieties to stabilize an emulsion. Bearing surfactant like properties, saponins act at the interface of two immiscible phases to reduce surface tension resulting in a uniformly dispersed homogenous system. The current chapter highlights the recent advancement/development of saponins stabilized micro, nanoemulsion, and future application in drug delivery.