Quantitative Analysis of the Efficacy and Potency of Novel Small Molecule Ice Recrystallization Inhibitors

Abstract

The effects of ice recrystallization are well-recognized throughout the literature. This phenomenon is the major cause for cellular damage during thawing of cells, ultimately reducing post-thaw viability and function. In this paper, we describe a method for quantifying the inhibitory effect on ice recrystallization of novel small molecules that are cryoprotectants for red blood cells. The method is ideally suited to the splat-cooling assay, where high-ice volume fractions are present. Using our method, we have derived first-order rate constants for the increase in the average crystal size based upon a “binning” approach of ice crystals as a function of size and time. Using this reliable metric, dose–response curves were constructed to obtain IC50 values. Two very effective inhibitors of ice recrystallization, p-methoxyphenyl β-d-glucopyranoside (PMP-Glc) and p-bromophenyl β-d-glucopyranoside (pBrPh-Glc), had IC50 values of 16.3 and 14.8 mM, respectively. Interestingly, the Hill slopes from these dose–resp...