Angilicam Avinash *, Karimunnisa Sk, Sumathi P
Department of Pharmaceutics, Sri Padmavathi School of Pharmacy, Vaishnavi Nagar, Tiruchanoor (Po), Tirupati, Andhra Pradesh, India-517503.
A B S T R A C T
The new drug molecules (more than 40%) are lipophilic in nature and showing poor water solubility and poor dissolution profile. Various techniques have been employed to formulate oral drug delivery system that would enhance the dissolution profile and in turn, the absorption efficiency of water insoluble drug. Solid dispersion, drug micronisation, lyophilisation, microencapsulation are some of the methods that have been used to enhance dissolution characteristics of water insoluble drugs. Among them, lipospheres are the promising particulate drug delivery systems for improving dissolution rate of water insoluble drugs. Lipospheres represents a novel drug delivery system in which water-insoluble lipid spheres forms a solid hydrophobic core, with a layer of phospholipids embedded on the surface of the core. Drugs or other biologically active agents may be contained in the hydrophobic core, in the phospholipid, attached to the phospholipids or a combination of the two. Lipid based carrier system (lipospheres) was adopted to eliminate the toxic effects associated with the use of polymers as carrier and entrapment of high amount of poorly bioavailable lipophilic compound. Due to its poor aqueous solubility of water insoluble or poorly soluble drug loaded lipospheres were found to be an effective natural carrier in terms of discrete particle size, encapsulation efficiency, and satisfactory in vitro release characteristics. The incorporated phospholipid could combine with drug by hydrophilic and hydrophobic interactions, consequently improved the drug entrapment efficiency and produced the sustained release rate.
Keywords: Lipospheres, Poor dissolution, Phospholipids, Sustained release