Self-microemulsion Technology for Water-insoluble Drug Delivery

: According to the drug discovery, approximately 40% of the new chemical entities show poor bioavailability due to their low aqueous solubility. In order to increase the solubility of the drugs, self-micro emulsifying drug delivery systems (SMEDDS) are considered as an ideal technology for enhancing the permeability of poorly soluble drugs in GI membranes. The SMEDDS are also generally used to enhance the oral bioavailability of the hydrophobic drugs. At present, most of the self-microemulsion drugs are liquid dosage forms, which could cause some disadvantages, such as the low bioavailability of the traditional liquid SMEDDS. Therefore, solid self-micro emulsifying drug delivery systems (S-SMEDDS) have emerged widely in recent years, which were prepared by solidifying a semi-solid or liquid self-emulsifying (SE) ingredient into a powder in order to improve stability, treatment and patient compliance. The article gives a comprehensive introduction of the study of SMEDDS which could effectively tackle the problem of the water-insoluble drug, especially the development of solidification technology of SMEDDS. Finally, the present challenges and the prospects in this field were also discussed.

Formulation and Pharmacokinetic Evaluation of Phosal Based Zaltoprofen Solid Self-Nanoemulsifying Drug Delivery System

Background: Phosal based excipients are liquid concentrates containing phospholipids. They are used to solubilize water-insoluble drug and also act as an emulsifier to get the smallest droplet size of the formed emulsion after administration. Objective: The aim is to prepare phosal based self nanoemulsifying drug delivery system (SNEDDS) for water insoluble drug zaltoprofen. Methods: The various parameters like solubility of drug in different vehicles, ternary phase diagram are considered to formulate the stable emulsion which is further characterized by Self emulsification time and globule size analysis to optimize liquid SNEDDS of Zaltoprofen. Optimized L-SNEDDS was converted into free-flowing powder Solid-SNEDDS (S-SNEDDS). S-SNEDDS was evaluated for Globule size analysis after reconstitution, in vitro dissolution study and in vivo pharmacokinetic study in rats. Results: Phosal 53 MCT with highest drug solubility was used as oil along with Tween 80 and PEG 400 as surfactant and cosurfactant respectively to prepare liquid SNEDDS. Neusilin us2 was used as an adsorbent to get free-flowing S-SNEDDS. S-SNEDDS showed improved dissolution profile of the drug as compared to pure drug. In vivo study demonstrated that there is a significant increase in Cmax and AUC of S-SNEDDS compared to zaltoprofen powder. Conclusion: Phosal based SNEDDS formation can be successfully used to improve the dissolution and oral bioavailability of poorly soluble drug zaltoprofen.

HYDROTROPIC SOLUBILISATION OF IRBESARTAN: MECHANISTIC STUDY AND DISSOLUTION PROFILING

Irbesartan (IB) is a water insoluble drug belonging to BCS II that exerts its anti-hypertensive effect through the blockage of angiotensin II receptors. The aqueous insolubility of IB limits its bioavailability and overall efficacy. Hydrotrophy, a solubilization technique to achieve an augmentation in aqueous solubility of poorly water-soluble drugs, has recently gained a lot of interest due to its safety, economics, and use of non-toxic and non-flammable adjuvants. The present study deals with application of hydrotrophy techniques to increase the solubility of IB using sodium benzoate and urea as the hydrotropic agent. The results showed a significant enhancement in dissolution profile of IB as compared to non-hydrotropic drug. The dissolution rate and solubility comparison of both hydrotropic agents revealed that sodium benzoate has a better solubilizing efficiency than urea. Hence, it can be concluded that hydrotropic concept can be adopted as a solubility enhancement technique for poorly water-soluble drugs.