Sporopollenin-based bio-microcapsules as green carriers for controlled delivery of pharmaceutical drugs

•Plant-made biocapsules offer advantages, as carriers, over synthetic microcapsules.•Biocapsules delivery and release strategy can be engineered to suit various purposes.•Advances in biocapsules have significantly improved orally administered pharmaceuticals.•Although two decades of research, biocapsules remain uncommercialized.•Regulatory and technical aspects still need to be addressed for the development of biocapsules.