Biocatalytic Synthesis of Phospholipids and Their Application as Coating Agents for CaCO3 Nano-crystals: Characterization and Intracellular Localization Analysis

Inorganic nanoparticles are widely investigated as drug delivery systems. In particular micro and nanoparticles of CaCO3 offer smart features for different biomaterials applications. In this work we exploit the phospholipids coating of nano-CaCO3. We prepare modified phospholipids through a chemo-enzymatic approach using Phospholipase D to efficiently transform the most abundant natural phospholipids in two products, snglycero-3-phosphocholine (GPC) and sn-glycero-3-phosphoserine (GPS). We have investigated and modified the Spray Drier process to obtain nano-crystals with specific phase, surface zeta-potential and morphology. The intracellular localization of coated nano-crystals was achieved by ultrastructural microscopy analysis. The synthetized phospholipids, GPC and GPS, improve nano-CaCO3 proprieties and promote a specific targeting as opposed to a widespread and nonspecific localization in the cell.