Solid Lipid Nanoparticles: a Novel Potential Carrier Approach

INTRODUCTION The field of Novel Drug Delivery System is emerging at an exponential rate with the deep understanding gained in diversified fields of Biotechnology, Biomedical Engineering and Nanotechnology. Many of the recent formulation approaches utilize Nanotechnology that is the preparation of Nanosized structures containing the API. Nanotechnology, as defined by the National Nanotechnology Initiative (NNI), is the study and use of structures roughly in the size range of 1 to 100 nm. The overall goal of ABSTRACT Solid lipid nanoparticles (SLNs) are the effective lipid based colloidal carriers which were introduced as an alternative to the conventional carriers such as micro emulsions, liposomes, micro particles and nanoparticles based on synthetic polymers or natural macromolecules. Typically they enhance the oral bioavailability of the low aqueous soluble drugs due to their potential to enhance gastrointestinal solubilization and absorption via selective lymphatic uptake. These properties can be harvested to improve the therapeutic efficacy of the drugs with low bioavailability, as well as to reduce their effective dose requirement. This paper presents an overview about the choice of the drug candidates, advantages, methods of preparation such as high pressure homogenization, ultrasonication/high speed homogenization, solvent evaporation/emulsification, supercritical fluid method, micro emulsion based method and spray drying method are discussed. Appropriate analytical techniques for characterization of solid lipid nanoparticles such as photon correlation spectroscopy, scanning electron microscopy, differential scanning calorimetry etc. are discussed. Applications with respect of routes of administration such as oral, parenteral, topical, pulmonary etc are elaborated in detail.