The effects of cooling rates (5

10

20

50

100 ℃/min) and solution concentration (0.5

1

2

3

4 mol/L) on the thermo-physical parameters of typical amino acid aqueous solutions ，such as L-lysine

L-proline

glycine ，and L-serine

were investigated viadifferential scanning calorimetry ( DSC). The results indicated that the effect of solution concentration on thermos - physical parameters of cryoprotectant solution was more significant than that of the cooling rate. At low concentrations (0. 5 mol/L and 1 mol/L) ，the unfrozen water content of L-proline was higher than that of other three amino acids. This indicates that the water-binding capacity of L-proline was higher than that of other three amino acids in low concentration solution. At high concentrations ( 2 mol/L and 3 mol/L)

the unfrozen wa-ter content of L-lysine was higher than that of the other three amino acids. Given that the concentration of the L-lysine functional group is higher than the other three amino acids in the same concentration solution and the longer molecular chain thereof leads to a lower probabili-ty of self-bonding of the functional group

a higher unfrozen water content was exhibited in the solution system.