Recrystallization-inhibition assay

The first generation C-linked analogs were assayed using two conventional techniques. These techniques are recrystallization-inhibition (RI) assay (29, 30) and nanoliter osmometry (31). The RI assay offers a distinct advantage in that it is effective at detecting antifreeze protein-specific activity at concentrations typically too low to cause a thermal hysteretic effect (29). 

Inhibition of Ice Recrystallization. IR inhibition assays were conducted as previously described". Briefly, samples are placed in capillary tubes and snap-frozen at about -35 C. They were then placed in the cryocycler chamber, with the temperature held at -6 C for >16 h. Digital images through crossed polarizing filters were taken of the capillaries immediately after they were placed in the chamber and at the end of the incubation period. Crystal size in the images was compared. Samples were classified as show ing IR inhibition if there was no apparent growth in the crystal size over time. 

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