Molecular Mechanisms in Drug Delivery

Knowledge of molecular mechanisms (MM) has been attracted globally due to its potential application in the field of drug delivery. In the past decades, several MM methods were identified with an extensive range of excipients for the reason of poor solubility of drugs. The MM has been scrutinized with complex formulations where the drugs are encapsulated into responsive excipients so that the drug delivery process has to be improved. This review gives brief information on mechanisms used in drug delivery such as swelling, diffusion, and erosion. In swelling controlled; the drug molecules permeate due to the formation of a hydrogel matrix. Impacting parameters in swelling controlled are temperature pH, light, pressure, ionic strength, magnetic and electric field, etc. In diffusion-controlled; the drug is released via excipient disintegration/cracks/leakages without a change in size. While erosion-controlled materials erode in the form of monomers and oligomers from excipient on the surface or bulk. These mechanisms depend on drug dose, drug type, quantity and type of excipient, and environmental conditions at the time of drug delivery. It also depends on the geometry and dimension of the administration routes. On the whole, this piece of information is useful to researchers for developing the drug delivery process.