In vitro simulation of vascular calcification by the controlled crystallization of amorphous calcium phosphates onto porous cholesterol

Abstract

The in vivo process of vascular calcification was simulated in vitro by a slow crystallization of a non-stoichiometric poorly crystallized carbonateapatite from Kokubo's revised simulated body fluid (rSBF) on the surface of a porous pellet made of pure cholesterol. To achieve this, the crystallization experiments were performed under strictly controlled conditions (similar to physiological ones) provided by a constant-composition double-diffusion (CCDD) device. To perform a closer match to in vivo conditions, rSBF was enriched by addition of glucose and bovine serum albumin (BSA) in physiological amounts. Precipitation took place on the surface of cholesterol and the precipitates consisted of poorly crystalline (almost amorphous) non-stoichiometric, sodium- and magnesium-contained carbonateapatite.