Statistical comparison of the results obtained by the proposed SPE sensors and the official methoda.
Taken (mol L−1) | Sensor 1 | Sensor 2 | Sensor 3 | Official method | |||||
---|---|---|---|---|---|---|---|---|---|
Found (mol L−1) | % recovery | Found (mol L−1) | % recovery | Found (mol L−1) | % recovery | Taken (μg mL−1) | Found (μg L−1) | % recovery | |
1 × 10−5 | 0.9823 × 10−5 | 98.23 | 0.9913 × 10−5 | 99.13 | 1.0023 × 10−5 | 100.23 | 2 | 1.991 | 99.55 |
5 × 10−5 | 5.057 × 10−5 | 101.14 | 4.942 × 10−5 | 98.84 | 4.917 × 10−5 | 98.34 | 4 | 4.0032 | 100.08 |
1 × 10−4 | 0.986 × 10−4 | 98.60 | 0.9945 × 10−4 | 99.45 | 0.99 × 10−4 | 99.00 | 6 | 5.887 | 98.12 |
5 × 10−4 | 4.988 × 10−4 | 99.76 | 4.982 × 10−4 | 99.64 | 4.9325 × 10−4 | 98.65 | 8 | 7.9086 | 98.87 |
1 × 10−3 | 1.0022 × 10−3 | 100.22 | 1.0087 × 10−3 | 100.87 | 1.011 × 10−3 | 101.10 | 10 | 9.909 | 99.09 |
Mean ± S.D. | 99.59 ± 1.189 | 99.58 ± 0.780 | 99.46 ± 1.162 | 99.14 ± 0.736 | |||||
% RSD | 1.194 | 0.783 | 1.168 | 0.742 | |||||
Variance | 1.414 | 0.609 | 1.350 | 0.541 | |||||
Student’s t-test | 0.716 (2.306)b | 0.925 (2.306)b | 0.523 (2.306)b | ||||||
F-value | 2.610 (6.338)b | 1.123 (6.338)b | 2.493 (6.338)b |
Official method (HPLC method using an octadecylsilane column and a methanol–0.01 mol L−1 ammonium phosphate buffer at pH 6.0 (60 : 40) as the mobile phase).
The values in parentheses are the corresponding tabulated t and F values at P = 0.05.