Bile acid transporter as a bioinspired method for oral therapeutics delivery system

Oral delivery of large macromolecules is indisputably considered the most acceptable route of administration; even though, various drug molecules fail in preclinical and clinical trials due to the harsh characteristics of gastric juice, enzymatic degradation, nontargeted delivery, and poor absorption and bioavailability. From the past few decades, researchers have more tended to design oral formulation targeting the bile acid transport system that facilitates a large permeation of macromolecules from the intestine to target sites. Usually, the bile acid transport system possesses both active and passive transport of oral formulations using the enterohepatic recirculating system. Various transport proteins, receptors, physicochemical, and biological factors and mechanisms are involved in this complex recycling route. Here, in this chapter, we have briefly explained bile acid and their transport system, reviewed the biophysical and biochemical roles of bile acid transporter (BAT), tried to disclose the unsolved questions so far and summarized the possible advantages of BAT regarding design and development of orally delivered macromolecules.