CaCO₃ Microparticle-Based Carriers: Optimization of BSA Loading by Coprecipitation

Oncological diseases, constituting a major global cause of death, require more selective treatments to minimize side effects. Immunotherapy using antibodies targeting immune checkpoints is a promising approach, but it is limited by poor tumor penetration and treatment resistance of cancer cells. The use of biocompatible and biodegradable calcium carbonate microparticles as drug carriers offers a solution due to their capacity for encapsulation of biomolecules and control of their release, which increase the therapeutic efficacy while reducing side effects. Our study was aimed at optimizing the synthesis of calcium carbonate microparticles and improving the loading of bovine serum albumin, used as a model protein, into them by means of coprecipitation. The approaches developed here make it possible to obtain protein carriers with advanced morphological characteristics and with a loading efficiency of more than 90%.