Polymeric nanoparticles are investigated as drug delivery devices to overcome physicochemical and pharmacokinetic (PK) problems. Many drugs were found to be drug-like during the pharmacological screening. However, all of them cannot make it to the market due to toxicity and poor bio-availability. The advent of nanoparticles has opened a new window of research where poorly soluble drugs are made useful. Nanoparticles have also been developed for favourable pharmacokinetics to avoid toxicity and side effects, to target the desired site of action and to provide triggered drug release. Poorly soluble drugs can be entrapped, encapsulated, coated or chemically bound in nanoparticles to deliver the drugs. Generally, in standard drug delivery, devices carry the drug until the gastrointestinal tract (GIT) and the drug is released, but the tool never expected to be entering the blood. However, in polymeric nanoparticles, sometimes the drug is being carried to the blood and the site of action. Polymeric nanoparticles release the drug in the gastrointestinal tract (GIT) or enter the GIT through various pathways to appear in the bloodstream. In this review, we discuss the fate of polymeric nanoparticles made up of biodegradable polymers after they are administered through the oral route.
Key words: Nanoparticle, Pharmacokinetics, Drug delivery, Polymer, Oral route.