A New Sensitive Sensor for Simultaneous Differential Pulse Voltammetric Determination of Codeine and Acetaminophen Using a Hydroquinone Derivative and Multiwall Carbon Nanotubes Carbon Paste Electrode

Table 3

Determination of codeine in human urine and serum samples using HTP-MWCNT-CPE.

Sample	Added (mol L^−1)		Found^a (mol L^−1)		RSD (%)		Recovery (%)
	COD	AC	COD	AC	COD	AC	COD	AC
Serum	—	—	<DL	<DL	—	—	—	—
	10.0	20.0	10.1 ± 0.1	19.9 ± 0.2	1.1	1.0	100.8	99.6
	20.0	20.0	19.9 ± 0.2	20.2 ± 0.2	1.0	1.0	99.4	101.0
	40.0	60.0	40.2 ± 0.4	59.9 ± 0.6	1.0	1.0	100.5	99.8
Urine	—	—	<DL	<DL	—	—	—	—
	10.0	20.0	9.9 ± 0.1	20.2 ± 0.2	1.1	1.0	99.1	100.9
	20.0	20.0	20.1 ± 0.2	20.1 ± 0.2	1.0	1.0	100.6	100.6
	40.0	60.0	40.2 ± 0.4	59.9 ± 0.6	1.0	1.0	100.6	99.8

Mean ± standard deviation ( = 4).