Preparation of bovine serum albumin based microcapsules and investigation of biological activities

ABSTRACT The design and development of functional synthetic microcompartments is a rapidly advancing research topic in fields such as synthetic biology, bioengineering, and nanomedicine. The construction of artificial cell-like systems, also called protocells, provides valuable insights into the fundamental mechanisms of cellular organization and creates innovative technological opportunities for drug delivery, enzymatic catalysis, and biomedical applications. In this study, we designed and fabricated artificial microscale compartments, called lipoproteinosomes, that mimic the structural and functional properties of biological systems. These microcapsules were formed by combining bovine serum albumin (BSA) with stearoyl chloride (SC) via a thiourea linkage. The formation process involved oil-in-water Pickering emulsification followed by stabilization by cross-linking, resulting in structurally stable and functionally versatile microcompartments. The developed lipoproteinosomes were shown to efficiently encapsulate a wide variety of molecules, ranging from water-soluble macromolecules to inorganic gold nanoparticles (AuNPs) and the bioorganic pigment prodigiosin. In particular, their ability to retain the pigment in the aqueous phase demonstrates their potential for transporting hydrophobic drugs and other bioactive molecules. In vitro experiments on cancer cell lines demonstrated that prodigiosin-loaded lipoproteinosomes are highly effective in targeted delivery, exhibit significant therapeutic effects, and enhance cellular uptake. In addition to their carrier role, the microcapsules were also shown to act as protocells, enabling enzyme-mediated communication. In conclusion, this research not only highlights the potential of natural amphiphilic compounds for the construction of functional microcompartments but also highlights the broad applicability of these systems in fields such as biomedicine, drug delivery, cancer therapy, protocell research, and microreactor technologies. Keywords: Lipoproteinosomes, Microencapsulation, Nanoconjugates, Bovine serum albumin