Drug carriers are primarily used to control the release of drug patterns into the circulation, which can be achieved through either moderate drug release over a long period of time (normally dispersion) or activated release at the drug's target in response to stimuli such as pH changes, temperature use, and light actuation. The ability to encapsulate pharmaceuticals is another feature of drug carrier. Drug carriers use their size and the spaces between cells in various tissues to passively target and accumulate in their intended target. Therapeutic drug carrier systems are designed technologies that allow medicinal drugs to be delivered with precision and/or controlled release. Many chronic diseases, including cancer, have a substantial impact on the treatment and potential cure of a range of drug carrier systems.