TABLE 5.

Stability of SRL in cryopreserved and fresh human whole blood (n = 3).

Matrix	Storage conditions		RE (%)	RSD (%)
Cryopreserved human whole blood	Room temperature stability	LQC	−2.0	7.5
	(25°C, 24 h)	HQC	0.5	11.2
	Freeze–thaw stability	LQC	0.0	6.7
	(−80°C, five cycles)	HQC	7.8	3.0
	Autosampler stability	LQC	10.7	12.0
	(4°C, 2 d 17 h)	HQC	7.0	3.3
	Long-term stability	LQC	13.3	6.5
	(−80°C, 31 d)	HQC	0.5	3.0
Fresh human whole blood	Room temperature stability	LQC	13.3	5.3
	(25°C, 24 h)	HQC	9.5	8.7
	Freeze–thaw stability	LQC	−10.0	13.3
	(−80°C, five cycles)	HQC	1.5	9.6
	Autosampler stability	LQC	8.7	12.9
	(4°C, 2 d 17 h)	HQC	3.2	8.0
	Long-term stability	LQC	9.3	0.6
	(−80°C, 31 d)	HQC	3.2	10.4

Note: RE, relative error; RSD, relative standard deviation; LQC, 1.50 ng/ml; HQC, 40.0 ng/ml.