Table 3.

Stability of VC in plasma and precipitant under various storage conditions (n = 6).

Matrix	Storage conditions	Time	Concentration (mg/L)		Precision	Accuracy
			Spiked	Measured	(%)	(%)
Plasma	Room temperature (RT)	0.75 h	1.5	1.32	3.67	88.17
			40	44.13	3.59	110.3
		1.5 h	1.5	1.13	6.15	75.17
			40	38.9	5.34	97.31
		3 h	1.5	1.02	10.04	67.82
			40	32.63	6.95	81.6
	4°C	2 h	1.5	1.32	8.09	88.1
			40	40.53	5.41	101.31
		4 h	1.5	1.2	5.85	79.67
			40	36.78	6.99	91.92
	−40°C	3 d	1.5	1.37	1.92	91.33
			40	38.15	2.57	95.36
		5 d	1.5	1.49	6.88	99.69
			40	41.82	7.62	104.62
		8 d	1.5	0.87	4.12	58.23
			40	34.77	4.17	86.94
Precipitant	RT	2 h	1.5	1.53	4.23	101.93
			40	39.12	2.12	97.76
		4 h	1.5	1.44	3.46	95.74
			40	38.08	2.16	95.23
	Long term (-40°C)	3 d	1.5	1.57	2.07	104.95
			40	42.85	7.49	107.18
		5 d	1.5	1.63	3.81	108.48
			40	39.17	2.86	97.9
Autosampler	Autosampler (4°C)	24 h	1.5	1.63	4.32	108.48
			40	44.47	3.32	111.17
Plasma	Three-freeze-thaw cycles		1.5	1.35	3.23	89.91
			40	43.15	1.34	107.82