A Review on Biomedical Applications of PolymericNanoparticles

Nanotechnology has achieved breakthrough in therapeutics, bioengineering, diagnostics, imaging, and optics in recent vintage [1]. The development of nanosystems by tailoring the macromolecules is the recent topic of interest. As nanoparticles possess extraordinary, often tunable properties dramatically different from the bulk materials, such as high surface to volume ratio, particle size and so forth there is an enormous demand for the tailor-made functional nanoparticle systems. Inorganic, organic or hybrid nanoparticular materials are used in various applications fields as medicine, pharmaceuticals, analytics, catalysis, coating, and several others. Nanoparticles are efficient and versatile devices for drug delivery as they can improve crucial properties of a drug entity such as solubility, pharmacokinetic, biodistribution and in vivo stability [2]. Due to their tailoring properties they can overcome physiological barriers and can help to guide their payload to specific cells or intercellular compartments. By which side effects can be minimized and therapeutic benefits of a drug can be increased. By virtue of their small size and by functionalizing their surface with polymers and appropriate ligands, polymeric nanoparticles can also be targeted to specific cells and locations in the body. Depending on the polymer characteristics, polymeric nanocarriers can also be engineered in such a way that they can be activated by changes in the environmental pH, chemical stimuli, or temperature. Macrophages are well recognized phagocytic cells of the reticuloendothelial system (RES) and one of the main cells responsible for the uptake and clearance of administered drug loaded nanoparticles. In general, once nanoparticles are opsonised, endocytosis/phagocytosis occurs, and the nanoparticles are incorporated in an endolysosome/phagolysosome and degrade [3]. However, the ability of various nanoparticles to escape the endolysomal compartment allows incorporated drugs to be delivered to the cytoplasm and finally to the nucleus. Thus, this property of the nanoparticles to be easily taken up by phagocytic cells makes them feasible to carry proteins, genes and other biological macromolecules as well [4]. Other applications include cytoplasmic release of plasmid vectors and therapeutic agents (e.g. for cytoplasmic infections and for slow cytoplasmic release of drugs that act on nuclear receptors) [5]. Depending on the preparation methods used, two different types of nanoparticles can be obtained, namely nanospheres and nanocapsules [6,7]. Nanoparticles are drug loaded particles with diameter ranging from 1 to 1000nm. Abstract Splendid achievements have been made in management of disease through invention of drugs over past decade. The present conventional drug delivery systems often have side-effects and complications due to their wide distribution throughout the body fluids. The localization of drug action in injured tissue is a promising way to solve this problem. The objective of drug targeting is to achieve a desired pharmacological response at a selected site without undesirable interaction at other sites. This is especially important in cancer chemotherapy and rheumatoid arthritis treatment. Recently invention of drugs has been generated by various drug delivery systems like microspheres, liposomes, noisomes, nanocapsules and nanoparticles. Among all colloidal drug carriers’ nanoparticles are gaining more popularity because of their stability, easy preparation, for achieving reduced toxicity, for increased drug efficacy & site targeted action. Nanoparticulation is a very useful strategy towards targeted drug delivery and also for enhancement of bioavailability of low soluble drugs. In this article nanoparticles preparation methods and their biomedical applications were discussed in detail.