“…the drug intracellular distribution, can be done using fluorescence based (confocal microscopy), Raman microspectroscopy and biochemical approaches. Therapeutic delivery of micromolecular drugs or macromolecular (siRNA) by in vitro studies, laboratory animals studies for therapeutic targeting, local delivery of drug loaded DDS by nanoparticulate vectors or some clinical studies were recently published [1][2][3][4][5][6][7]. Achieving such a goal is possible by giving some physicochemical properties for DDS able to overcome the physiological and intracellular barriers, by providing the desired bioavailability of the bioactive drug, its intracellular pharmacokinetics and its desired biological or pharmacological effect.…”