Recent advances on drug delivery applications of mucopenetrative/mucoadhesive particles: A review

The human body is made up of various external skin barriers to fight disease and infection. One such barrier is mucus, which not only protects and lubricates the exposed epithelia by preventing entry of pathogens, unwanted particles, and debris, but also prevents diffusion of mucosal drug delivery. In recent decades, mucoadhesion has received much attention for various drug delivery systems that involve the interaction between the dosage form and the mucosal surface. Transmucosal administration has become challenging due to various factors affecting the mucus barrier properties, mainly particle size, thickness, interaction of the particles with the mucosa, clearance time and rate. This review article describes the role, composition, and physicochemical properties of a mucus that affects penetration and aims to provide scientists with a roadmap to conduct high-quality research for the design and development of mucoadhesive delivery systems such as buccal, nasal, gastrointestinal, pulmonary, and vaginal through surface modification to avoid rapid clearance, ensure targeted and sustained drug delivery, improve residence time and the overall therapeutic efficacy of a drug, along with easy permeation of particles through the mucosal surface for efficient treatment of diseases with fewer side effects.