3.2. Method performance
Under the optimum conditions as those described above, the
calibration graph of ECL intensity versus naproxen concentration
was linear in the range of 4.0×10−8gmL−1 to 2.0×10−6gmL−1; the
regression equation was I=1077.1C + 12.05 (C: naproxen concentration,
10−6gmL−1) with a correlation coefficient of 0.993. The limit
of detection (LOD) was 1.6×10−8gmL−1 (S/N = 3). As compared in
Table 1, the present method has a wider linear range, lower or comparative
detection limit than some of the previously reported HPLC
methods.