The branches of science like Nano medicine, Nano technology, Nano chemistry and Nano science are a few of those departments that have the word ’nano’ in their name and were frequently published in books and journals and became familiar to the public and the research professionals too. It was an emerging science in the 20th century and is the trend currently. It is not a single isolated technique or method that is applicable in one field, but it is multi-dimensional and is applied in various fields considering the advantages. Its arena ranges from the synthesis, designs, large scale production and potential application of nano-sized materials. They are the systems of a matrix of drug carriers that are uniformly dispersed in the polymeric membranes. This review concentrates on the methods of preparation of nano particles, evaluation methods, advantages and applications of nano particles in medicine. Nanotechnology mostly provides better drug delivery in order to transfer into the smaller parts of the body. This is mostly implemented to enter the ultrathin areas in the body. So, the drugs such as genetic medicine can easily permeated into the cell walls to produce maximum growth within a few more years. The doctors are paid by the patients. The patients who are receiving this therapy shows better bioavailability, decreased drug toxicity, lesser cost of treatment, and extend the life of proprietary drugs. © 2021 Elsevier B.V., All rights reserved.