Development of a Flow Injection System for Differential Pulse Amperometry and Its Application for Diazepam Determination

Table 4

Analysis results of the recovery for spiked samples ().

Sample	Spiked concentration (µmol/dm^3)	Results (mean ± SD) (µmol/dm^3)	Recovery ratio (%)
Guarana	50	52.48 ± 0.80	104.96
	100	101.25 ± 1.55	101.25
	150	152.05 ± 2.33	101.37
Beer I	50	47.51 ± 0.73	95.02
	100	94.31 ± 1.44	94.31
	150	139.48 ± 2.13	92.99
Beer II	50	49.12 ± 0.75	98.24
	100	96.24 ± 1.47	96.24
	150	141.66 ± 2.17	94.44