Urine Sample

added
(×10-6 mol l-1)

Found
(×10-6 mol l-1)

Average recovery
(%, n = 5)

R.S.D.
(%, n = 5)

1

2

3

0.70
3.00
0.70
3.00
0.70
3.00

0.72
2.90
0.74
3.13
0.69
3.22

103
97
106
104
99
107

2.2
1.7
1.8
2.9
2.6
1.9

Table 2: Results for the determination of isoniazid in spiked urine samples