Nanocrystal Technology For Oral Delivery of Poorly Water-Soluble Drugs

Nanotechnology has been improving and has a variety of application fields. One of the major application areas of nanotechnology in pharmacy is nanoparticular drug delivery systems. Preparation of drug nanocrystals to improve the solubility of poorly water-soluble drugs for oral delivery is also one of the important applications. Nanocrystal dispersions comprise water, active drug substance and a stabilizer. They are physically stable due to the presence of stabilizers that prevent reagragregation of the active drug substance. Different techniques can be used to prepare nanocrystal formulations of a drug powder such as homogenization, coprecipitation, spray drying and milling. There are several advantages of nanocrystal formulations such as, enhanced oral bioavailability, improved dose proportionality, reduced food effects, suitability for administration by all routes and possibility of sterile filtration due to decreased particle size range. The first nanocrystal drug product, Rapamune® (Sirolimus), was approved by the FDA in 2000. In the following years, several other nanocrystal drug products came out on the pharmaceutical market. Nanocrystal technology is cheap and easy to apply; thus, it appears that this technology will be substantially useful for the manufacture of poorly water-soluble drug products for oral delivery.