Zein coated calcium carbonate nanoparticles for the targeted controlled release of model antibiotic and nutrient across the intestine

In this study, a novel bio-inspired method was used to synthesize calcium carbonate nanoparticles (CaCO3 NPs) using gelatin as a template for the co-delivery of vitamin D and amoxicillin. The synthesized CaCO3 NPs were characterized using Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET). XRD and TEM confirmed nanocrystalline nature of CaCO3 in size range of 10-15 nm. Further, CaCO3 NPs encapsulated with vitamin D, coated with zein and finally loaded with amoxicillin as a model drug. The release study of vitamin D and amoxicillin was performed in the simulated gastric fluid (SGF) (pH 1.2) and simulated intestinal fluid (SIF) (pH 6.8) and (pH 7.4) at 37 degrees C temperature. The encapsulation of hydrophobic vitamin D in CaCO3 NPs with an external zein coating approach enhances their controlled and sustained release property at the target site. The role of gelatin molecule in the synthesis of nano-sized CaCO3 was demonstrated using CD spectroscopy. MTT assay was performed on zein coated CaCO3 NPs at varying concentrations on kidney (HEK) and liver (Hep G(2)) cell lines after 24 h exposure to ensure its biocompatibility.