Direct observation of cholesterol monohydrate crystallization

Area of Science:

• Biochemistry
• Crystallography
• Materials Science

Background:

• Cholesterol crystallization is implicated in atherosclerosis and gallstones.
• Mechanisms governing cholesterol crystal growth remain poorly understood.

Purpose of the Study:

• To elucidate the real-time dynamics of cholesterol monohydrate crystal growth.
• To identify the mechanisms driving crystal surface morphology and growth rates.

Main Methods:

• Utilized a biomimetic water-isopropanol solvent system for controlled crystallization.
• Employed in situ techniques including time-resolved imaging and atomic force microscopy (AFM).
• Conducted microfluidics measurements to analyze crystal growth dynamics.

Main Results:

• Cholesterol monohydrate crystals exhibit classical growth via nucleation and layer spreading.
• Crystal growth is mediated by dislocations and monomer diffusion along the surface.
• Abundant macrosteps were observed, leading to a self-inhibition of crystal growth.

Conclusions:

• Cholesterol crystal growth follows classical mechanisms but is uniquely regulated by self-inhibition.
• Understanding these growth dynamics is crucial for addressing cholesterol-related pathologies.
• The findings provide a novel perspective on crystal growth regulation in biological systems.