Surface Modification of Micronized Drug Particles for Aerosolization

Abstract

Generally, a lung disease means any type of disease or disorder which does not allow the lungs to work efficiently. The lower respiratory tract diseases include chronic obstructive pulmonary disease (COPD), emphysema, asthma, and chronic bronchitis. Moreover, lung cancer, the most frequently diagnosed cancer, affects the lungs by developing malignant cells. Lungs possess a wide surface area so that they could be used as a spot for particle deposition for drug delivery applications. However, to target drugs directly to the lungs, there are multiple barriers such as mechanical, chemical and immunological, biological, and behavioral. Therefore to overcome these barriers, surface engineering of the particles for better pulmonary delivery is one of the potential strategies. The primary deposition mechanisms include inertial impaction, gravitational sedimentation, and Brownian diffusion. Particle engineering involves polysaccharides, amino acids, and cyclodextrins by employing spray drying, solvent evaporation, nano-in-micro particles, and dialysis methods. The delivery of surface-engineered nanotechnology-enabled drug delivery systems such as organic (lipid, polymer, hybrid nanoparticles) and inorganic nanoparticles (metal-organic frameworks, silica nanoparticles) via pulmonary delivery is a relatively new but emerging strategy to treat lung diseases. This chapter offers an overview of particle engineering for better aerosolization. Herein, we discuss various mechanisms of particle deposition in the respiratory tract via lung delivery. Then, state-of-art particle engineering based on the sugars, amino acids, and cyclodextrins is described. The surface engineering of the particles intended for lung delivery would offer an opportunity for formulation scientists to bridge the preclinical and clinical gaps.