Effect of Temperature and Duration Time of Maceration on Nitrate Content of Vernonia cinerea (L.) Less.: Circumscribed Central Composite Design and Method Validation

Table 2

Precision and accuracy results.

Concentration (μg/mL)	Precision (%RSD)				Spike concentration (μg/mL)	Accuracy
	Repeatability			Intermediate		%Recovery
	Day 1	Day 2	Day 3
25	0.24	0.03	0.09	0.50	25	102.46
50	0.09	0.04	1.12	0.67	50	97.58
75	0.07	0.07	0.13	0.28	75	101.68