Dual-Function Small-Molecules Capable of Controlling Ice Nucleation and Ice Recrystallization

Uncontrolled ice formation and subsequent growth causes irreversible damage to cells during cryopreservation. Ice recrystallization inhibitors (IRIs) reduce ice crystal growth after nucleation and have proven beneficial for cryopreservation. Controlling ice nucleation can also minimize iceinduced injury and improve the reproducibility of freezing protocols. However, synergy between compounds that influence these processes remains largely unexplored. Herein, we evaluate seven biocompatible carbohydrate-based small-molecules and report that select compounds – 4bromophenyl-β-D-glucose (β-pBrPh-Glc, 1), 4-methoxyphenyl-β-D-glucose (β-PMP-Glc, 2), N-2fluorophenyl-D-gluconamide (2FA, 5), and N-4-chlorophenyl-D-gluconamide (4ClA, 6) – exhibit dual ice-modulating activity, defined as the ability to inhibit ice recrystallization and induce synchronous nucleation, representing a novel mode of ice nucleation control not previously reported. Our results confirm that nucleation control is dependent on carbohydrate structure, where glucose-based molecules are sensitive to AgI-mediated nucleation, producing small ice crystals, whereas galactose-based analogs are insensitive to AgI-mediated nucleation. Overall, our findings reveal that the synergy of ice nucleation and ice recrystallization inhibition is structure- and solvent-dependent.