Review: Nanopreparations for better drug delivery

Nanomedicines are a recent development to face medical and pharmaceutical challenges because nanoparticles have unique properties. They are very small in size and are easy to handle. One more advantage is that they are not harmful for the human body. Poorly soluble drugs have serious problems with their delivery and dosage forms. Formulation strategies by means of nanocarrier systems, such as polymeric micelles, can resolve the trouble. Micelles from PEG-diacyllipids, e.g. PEG-PE, are of special attention. On the other hand, the layer-by-layer (LbL) technique can be useful to set up stable nanocolloids of low solubility. In some cases, the use of nanopreparations is the only way to fulfill medical requirements. Thus, for the blood group CT imaging, one has to prepare long-circulating contrast-loaded nanoparticles. In other cases, poor stability of potential drugs creates a problem, such as with siRNA, and the use of nanocarriers may present a solution e.g. Polymeric micelles having a hydrophobic derivative of siRNA. We will discuss the preparation, properties, and anti-cancer activity of drug-loaded PEG-PE micelles and LbL nanoparticles and other "approaches" for making "undeliverable" substances deliverable. Injectable, implantable, topical delivery of active compounds, oral drug delivery system and many other methods have been improved by nanotechnology.