Encapsulation methods of active molecules for drug delivery

43 Recent years have witnessed the emergence of nanotechnology in the medicinal field 44 in order to improve existing treatments and develop novel and efficient therapies. 45 Nanostructured systems have attracted unprecedented interest in drug delivery due to their 46 ability to overcome difficulties linked to conventional drug delivery systems. Nanocarriers 47 increase drug solubility and permeability, improve bioavailability, reduce side effects and 48 enhance the therapeutic efficiency, whilst providing a preferential accumulation of active 49 molecules at specific tissue sites or cells. The present chapter highlights the different 50 elaboration processes leading to the development of two main groups of organic nanocarriers; 51 lipid based-nanocarriers (including liposomes and solid lipid nanoparticles) and polymer 52 based-nanocarriers (including polymeric nanoparticles). These carriers are used to encapsulate 53 and to deliver active molecules or in some cases, for in vitro diagnosis and more recently in 54 theranostics applications.