Abstract:
Conventional drug delivery systems such as tablets or capsules deliver the drug in abrupt way. Therefore, concentration of the drug in blood plasma drops below the minimum effective concentration, resulting loss of therapeutic activity of the drug. Fluctuation of the drug concentration in the blood may cause unnecessary side effects and treatment become cost effective. To overcome this situation, sustained/controlled drug delivery systems are required which can diminish the undesired fluctuations and enhance the therapeutic efficacy. Controlled drug delivery system delivers the drug at the right place, at the right concentration for the right time of period. Now a day, great attentions have been paid to the polymeric controlled drug delivery systems. Polymeric drug delivery systems are of great interest because of their wide range of hydrophobic and/or hydrophilic components and their polymer-polymer, polymer-drug, polymer-solvent, or polymer-physiological medium interactions. Therefore, special attentions have been given to design polymeric controlled drug delivery systems. Both synthetic and naturally occurring polymer, such as polysaccharides can be explored to design controlled drug delivery systems but naturally occurring biopolymers are preferable because of their inherent nontoxic, biodegradable nature and low cost.
