TY - JOUR
T1 - Confinement-Controlled Crystallization of Guanine
AU - Li, Chuen Ru
AU - Wittig, Nina Kølln
AU - Køppen Christensen, Thorbjørn Erik
AU - Østergaard, Maja
AU - Garrevoet, Jan
AU - Birkedal, Henrik
AU - Amstad, Esther
PY - 2024/6/25
Y1 - 2024/6/25
N2 - Guanine crystals are frequently encountered in nature in the β-polymorph to create structural colors, to enhance the vision of creatures, and for camouflage. Unfortunately, it is challenging to control the crystallization of guanine in aqueous conditions in the laboratory because of its low solubility in water. Here, we crystallize guanine in an aqueous environment under confinement. We employ water-oil-water double emulsions stabilized with a metal-ligand functionalized surfactant as selectively permeable containers to crystallize guanine by dynamically adjusting the pH and guanine concentration. If formed under high osmotic pressures that result in high guanine concentrations within emulsion cores, guanine crystallizes into the anhydrous β-polymorph with a spherical morphology. In contrast, if crystals form within emulsion cores containing low guanine concentrations, they attain the monohydrate form possessing a needle-like morphology. These findings demonstrate for the first time that the structure and morphology of guanine crystals formed in the laboratory under confinement in an aqueous environment can be tuned by the local guanine concentration and to some extent by the solution pH.
AB - Guanine crystals are frequently encountered in nature in the β-polymorph to create structural colors, to enhance the vision of creatures, and for camouflage. Unfortunately, it is challenging to control the crystallization of guanine in aqueous conditions in the laboratory because of its low solubility in water. Here, we crystallize guanine in an aqueous environment under confinement. We employ water-oil-water double emulsions stabilized with a metal-ligand functionalized surfactant as selectively permeable containers to crystallize guanine by dynamically adjusting the pH and guanine concentration. If formed under high osmotic pressures that result in high guanine concentrations within emulsion cores, guanine crystallizes into the anhydrous β-polymorph with a spherical morphology. In contrast, if crystals form within emulsion cores containing low guanine concentrations, they attain the monohydrate form possessing a needle-like morphology. These findings demonstrate for the first time that the structure and morphology of guanine crystals formed in the laboratory under confinement in an aqueous environment can be tuned by the local guanine concentration and to some extent by the solution pH.
UR - http://www.scopus.com/inward/record.url?scp=85196020683&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.4c00550
DO - 10.1021/acs.chemmater.4c00550
M3 - Journal article
AN - SCOPUS:85196020683
SN - 0897-4756
VL - 36
SP - 6038
EP - 6046
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 12
M1 - 36
ER -