Pollen-derived microcapsules for aspirin microencapsulation: <i>in vitro</i> release and physico-chemical studies

Abstract

Aspirin, also known as acetylsalicylic acid (ASA), is one of the most crucial therapies needed and/or used in a basic health system. Using biocompatible materials to encapsulate ASA would improve its therapeutic efficacy and reduce its side effects <i>via</i> controlled release in physiological environments. Consequently, we explore in this study the feasibility of encapsulation of ASA into robust <i>Lycopodium clavatum</i> L. sporopollenin (LCS) microcapsules. After extracting sporopollenin from their natural micrometer-sized raw spores, the physico-chemical features of the extracted sporopollenin, pure ASA, and sporopollenin loaded with ASA were characterised using various methods, including optical microscopy, Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-vis.) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Additionally, we demonstrate the <i>in vitro</i> release profile of ASA in a triggered gastrointestinal environment utilizing kinetics analysis to investigate the mechanism of release. The LCS microcapsules were found to be excellent encapsulants for the crucial ASA drug and achieved controlled <i>in vitro</i> release, that would enable further investigations to rationally design versatile controlled delivery platforms.