A new automated method for the determination of the Total Antioxidant Capacity (TAC) of human plasma, based on the crocin bleaching assay

Table 2 Effect of repeated freezing cycles on TAC values

Anti-coagulant	Number of freeze/thawing cycles
	1	2	3	4	5
K₃-EDTA	1.05 ± 0.02	1.00 ± 0.02	1.05 ± 0.03	1.13 ± 0.03	1.22 ± 0.04
Heparin	1.05 ± 0.03	0.95 ± 0.02	1.00 ± 0.03	1.24 ± 0.04	1.32 ± 0.05

Ten different plasma samples from normal individuals, collected on K₃-EDTA or heparin, were assayed after a number of 1–5 freeze/thawing cycles, by the automated TAC assay. Values are presented as the mean ± SEM. The target value of non-freezed plasma, collected in a K₃-EDTA tube was given in Table 1

ISSN: 1472-6890