Intercellular tight junctions represent a formidable barrier against paracellular drug
absorption at epithelia (eg, nasal, intestinal) and the endothelium (eg, blood–brain barrier) …

The intestinal epithelium, the largest interface between the host and environment, regulates
fluxes of ions and nutrients and limits host contact with the massive load of luminal antigens …

In order for therapeutic agents to exert their pharmacological effects, they have to cross the
biological membranes into the systemic circulation and reach the site of action. Drugs cross …

One of the major hurdles in developing therapeutic agents is the difficulty in delivering drugs
through the intestinal mucosa and blood-brain barriers (BBB). The goal here is to describe …

The anatomical and functional arrangement of the gastrointestinal tract suggests that this
organ, beside its digestive and absorptive functions, regulates the trafficking of …

Peroral delivery of hydrophilic drugs is one of the greatest challenges in biopharmaceutical
research. Hydrophilic drugs usually present low bioavailability after oral administration. One …

As biologics used in the clinic outpace the number of new small molecule drugs, an
important challenge for their efficacy and widespread use has emerged, namely tissue …

The intent of this paper is to update the reader on various strategies which have been
utilized to increase the paracellular permeability of protein and polypeptide drugs across the …

Introduction: Inclusion of absorption-enhancing agents in dosage forms is one approach to
improve the bioavailability of active pharmaceutical ingredients with low membrane …

Background Oral delivery of macromolecules has been limited mainly by their low intestinal
permeability. Chemical permeation enhancers (CPEs) are typically used to improve …