Hydroxycitrate is a Unique Inhibitor of Pathologically-Relevant Brushite Crystallization

Area of Science:

• Crystallization science
• Biomineralization
• Materials science

Background:

• Crystal formation is controlled by molecular interactions with surfaces, influencing natural, biological, and synthetic processes.
• Modifiers can inhibit or promote crystallization, enabling unique properties or metastable polymorphs.
• Pathological crystallization involves native or designed molecules to suppress crystal nucleation and growth.

Purpose of the Study:

• To assess hydroxycitrate as a modifier of brushite crystallization.
• To compare the inhibitory efficacy of hydroxycitrate with citrate.
• To investigate the mechanism of action of hydroxycitrate in brushite formation.

Main Methods:

• Bulk crystallization experiments
• Microfluidics
• Atomic force microscopy (AFM)

Main Results:

• Hydroxycitrate completely suppresses brushite nucleation.
• Hydroxycitrate is an effective growth inhibitor at concentrations one order of magnitude lower than citrate.
• Hydroxycitrate inhibits two principal growth directions, while citrate inhibits only one.

Conclusions:

• Hydroxycitrate demonstrates superior efficacy in inhibiting brushite crystallization compared to citrate.
• The findings suggest hydroxycitrate's potential for developing potent inhibitors of pathological crystallization.
• This research has implications for understanding and treating other biomineralization disorders.