Biomineralization and Properties of Guanine Crystals

Abstract

Guanine crystals with unique optical properties in organisms have been extensively studied and the biomineralization principles of guanine are being established. This review summarizes the fundamental physicochemical properties (solubility, tautomers, bands, and refractivity), polymorphs, morphology of biological and synthetic forms, and the reported biomineralization principles of guanine (selective recrystallization of amorphous precursor, preassembled scaffolds, additives, twinning, hypoxanthine doping, fluorescence, and assembly). The biomineralization principles of guanine will be helpful for the synthesis of guanine crystals with excellent properties and the design of functional organic materials for drugs, dyes, organic semiconductors, etc.

Confinement-Controlled Crystallization of Guanine

“…The fascinating optical properties of photonic systems incorporating guanine crystals arise from its very high refractive index, n = 1.83. These optical properties inspired a lot of work devoted to the formation of the β-polymorph of guanine. ,− Yet, the controlled crystallization of guanine under synthetic conditions is hampered by its low solubility in water . Guanine crystals exhibiting the β-polymorph can be produced from organic solvents, such as formamide, dimethyl sulfoxide (DMSO), and dimethylformamide (DMF) .…”