Mutual Relationships of Nanoconfined Hexoses: Impacts\non Hydrodynamic Radius and Anomeric Ratios

Although all hexose sugars share\nthe same chemical formula, C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>, subtle differences in their stereochemical\nstructures lead to their various biological roles. Due to their prominent\nrole in metabolism, hexose sugars are commonly found in nanoconfined\nenvironments. The complexity of authentic nanoconfined biological\nenvironments makes it challenging to study how confinement affects\ntheir behavior. Here, we present a study using a common model system,\nAOT reverse micelles, to study hexose sugars in nanoconfinement. We\nexamine how reverse micelles affect the hexoses, how the hexoses affect\nreverse micelle formation, and the differences between specific hexoses:\nglucose, mannose, and galactose. We find that addition of glucose,\nmannose or galactose to reverse micelles that already contain water\nleaves their size smaller or nearly unchanged. Introducing aqueous\nhexose solution yields reverse micelles smaller than those prepared\nwith the same volume of water. We use <sup>1</sup>H NMR to show how\nthe nanoconfined environment impacts hexose sugars’ anomeric\nratios. Nanoconfined mannose and galactose display smaller changes\nin their anomeric ratios compared to glucose. These conclusions may\nprovide insights about the biological roles of each hexose when studied\nunder a more authentic nanoconfined system.