Fabrication of calcium phosphates with controlled properties using a modular oscillatory flow reactor

Abstract

Several technologies and synthesis routes have been implemented to produce calcium phosphates (CaPs) with distinct characteristics for biomedical applications. However, produce CaPs in a controlled way still represents a challenge. Oscillatory flow reactors (OFRs) are a technology ready to deliver in terms of mixing intensification in multiphase systems. In particular, continuous processes in OFRs improve control over the reaction conditions and can be implemented at an industrial scale. The aim of this work was to study for the first time the influence of the oscillation amplitude (x0: 4, 8 and 18 mm) and frequency (f: 1.9, 4 and 6 Hz) as well as residence time (τ: 3.3, 6.6 min) on the final CaP particles’ physicochemical properties using a continuous precipitation process in a novel modular oscillatory flow plate reactor (MOFPR). Furthermore, other parameters such as the initial reagents concentration, initial Ca/P molar ratio (Ca/P = 1.67, 1.33) and temperature (T = 37, 54 ºC) were also assessed. The synthesized particles and overall process were compared with particles obtained using the same methodology in conventional reactors, evidencing the potential of this technology to fabricate CaPs with tailored properties for potential application as nano or microcarriers for biomedical applications.