To establish an evaluative method to characterize physiological activity of red blood cells (RBC) affected by polysorbate 80. In the experiment, a microcalorimetric technique was used to investigate kinetic variation of energy metabolism of RBCs, which was evaluated quantitatively by the parameters of decay rate constant (k), maximum power (P_max), the total quantity of heat (Q), decay time (t) taken from P-t curves. The results indicated that characteristic parameters of k, Q and t decreased, and P_max increased with the concentration of the polysorbate 80 increasing. Furthermore, there was a good linear relationship between Q, k and C (coefficient correlation r??0.95), and the total quantity of heat (Q) of two factories had significant difference (P??0.05). In contrast with method of macroscopic observation, spectrophotometry and cell counting, microcalorimetry has advantage of real-time, full-scale information in determining the dynamic process of physiological activity of RBCs, especially in measuring sub-lethal cells. It is suggested that this method can be used to bioassay quality of polysorbate 80, and provides reference to related investigation of living cells.

Key words: microcalorimetry, solubilizing excipient, polysorbate 80, red blood cells, physiological activity