Abstract
BACKGROUND: The rapid, simple determination of surfactants in environmental samples is essential because of the extensive use and its potential as contaminants. We describe a simple, rapid chemiluminescence method for the direct determination of the non-ionic surfactant Triton X-100 (polyethylene glycol tert-octylphenyl ether) in environmental water samples. The optimized experimental conditions were selected, and the mechanism of the Luminol-H2O2-Triton X-100 chemiluminesence system was also studied. RESULTS: The novel chemiluminescence method for the determination of non-ionic surfactant Triton X-100 was based on the phenomenon that Triton X-100 greatly enhanced the CL signal of the luminol-H2O2 system. The alkaline medium of luminol and the pH value obviously affected the results. Luminol concentration and hydrogen peroxide concentration also affected the results. The optimal conditions were: Na2CO3 being the medium, pH value 12.5, luminol concentration 1.0 x 10(-4) mol L(-1), H2O2 concentration 0.4 mol L(-1). The possible mechanism was studied and proposed. CONCLUSION: Under the optimal conditions, the standard curve was drawn up and quotas were evaluated. The linear range was 2 x 10(-4) g mL(-1)-4 x 10(-2) g mL(-1) (w/v), and the detection limit was 3.97 x 10-5 g mL(-1) Triton X-100 (w/v). The relative standard deviation was less than 4.73% for 2 x 10(-2) g mL(-1) (w/v) Triton X-100 (n = 7). This method has been applied to the determination of Triton X-100 in environmental water samples. The desirable recovery ratio was between 96%-102% and the relative standard deviation was 2.5%-3.3%. The luminescence mechanism was also discussed in detail based on the fluorescence spectrum and the kinetic curve, and demonstrated that Triton X-100-luminol-H2O2 was a rapid reaction.