Polysorbate-Phospholipid Complex Micelles as P-glycoprotein Inhibitor Drug Delivery System

Abstract

Presystemic metabolism and selective transport mechanism are the two important defensive systems with which drug molecules from the time of its release till its elimination through the body interacts. ATP-based transport enzyme P-gp present at the extracellular surface allows selective localization of drugs inside the cytoplasm. This selective transport effluxes the xenobiotics and toxins entering inside thus preventing any harmful effect from occurring but such cohesive effect may result into the shielding of the active drug molecule to produce a desirable pharmacological response. Varieties of inhibitors are available but the use of such molecules to produce a drug delivery system is a confronting task. Polysorbate-Phospholipid complex particles are not considered as the common P-gp inhibiting mechanism but their fruitfulness towards the delivery of drug molecules inside with enhanced residence at the brain, placenta, heart, ovaries and testes tissues proved its efficiency as prominent inhibitors. Coating of Polysorbate 80 is considered as crucial due to its ionic stability and micellization for achieving targeting of the drug at tissues. Use of Phospholipid for the site specific delivery of drugs is very common; they are the building blocks of cells which allow the transport of active drug molecules into the cellular system without any inhibition by any efflux mechanism. Phospholipids also enhance the bioavailability of pharmaceutical products with less membrane penetration potential and less aqueous solubility. In this review, the key points of various literature with more rationalized view are noted to highlight the effectiveness of Polysorbate-80/phospholipid mixed micelles as P-gp inhibitors.