Praziquantel-loaded calcite crystals: Synthesis, physicochemical characterization, and biopharmaceutical properties of inorganic biomaterials for drug delivery.

Drug delivery systems impacted significantly biomedical research, and the number of nano- and microformulations recently approved for clinical trials or marketed increased. Raw materials-based drug delivery systems have currently organic and inorganic origin, and calcium carbonate particles demonstrated several potentialities in biomedical applications and controlled drug delivery as well as they are safe and biocompatible. The aim of this study was the synthesis of calcium carbonate particles to improve the dissolution rate of praziquantel, a poorly water-soluble drug which is the gold standard for the treatment of parasite infections. Calcium carbonate particles were obtained using a synthetic carbon-based approach. Physicochemical properties of calcium carbonate particles, with or without praziquantel, were carried out by using scanning electron microscopy, Fourier transformed infrared spectroscopy, X-ray powder diffraction, thermal gravimetry and differential scanning calorimetry analysis. The solid-state characterization of calcium carbonate particles demonstrated that calcite crystals are synthesized, and these crystals interact specifically with praziquantel. The release profiles of praziquantel from calcium carbonate particles were further studied using United States Pharmacopeia dissolution test and the amount of drug released was quantified by using high performance liquid chromatography. Calcium carbonate particles increased the dissolution rate of praziquantel, which is higher than pure crystalline drug. Resulting data may suggest a potential application of these inorganic particles for oral and controlled release of praziquantel and their potential use as novel therapy for human helminthes infections.