Inorganic phosphates reversibly grafted with bioactive compounds and a method of their preparation

Abstract

Biologically active solid systems are disclosed, containing immobilized organic compounds, such as medicines, in the form of materials appropriate as bone fillers, implant coatings or other alike systems, of the common formula B—P-A, where B is an inorganic support consisting of calcium phosphate, calcium hydroxyphosphate (hydroxyapatite), their mixture, or some other biocompatible mixture containing these or other insoluble inorganic phosphates, —P— is a phosphoryl group —P—O—, and A is the residue of the immobilized, organic, biologically active compound, such as a medicine, containing unprotonated amine and/or hydroxide group(s), and a method of their preparation consisting of the treatment of inorganic phosphate with a grafting reagent and consequent reaction with organic compound. As a grafting reagent, phosphorus pentachloride is applied and all operations are completed in an aprotic solvent. The advantage of the above product is the extension of the time duration of release of the immobilized organic compound such as a medicine from the surface, the release of the organic compound in its initial, unaltered, fully biologically active form, in the absence of any toxic or alien side products of hydrolytic decomposition of the immobilized system.

Dependencies are inferred from the claim text.