A facile electrochemical sensor for the determination of nonylphenol (NP) was fabricated in this work. Cetyltrimethylammonium bromide (CTAB), which formed a bilayer on the surface of the carbon paste (CP) electrode, displayed a remarkable enhancement effect for the electrochemical oxidation of NP. Moreover, the oxidation peak current of NP at the CTAB/CP electrode demonstrated a linear relationship with NP concentration, which could be applied in the direct determination of NP. Some experimental parameters were investigated, such as external solution pH, mode and time of accumulation, concentration and modification time of CTAB and so on. Under optimized conditions, a wide linear range from 1.0 × 10 ？7 mol·L ？1 to 2.5 × 10 ？5 mol·L ？1 was obtained for the sensor, with a low limit of detection at 1.0 × 10 ？8 mol·L ？1. Several distinguishing advantages of the as-prepared sensor, including facile fabrication, easy operation, low cost and so on, suggest a great potential for its practical applications.
References
[1]
Frassinetti, S.; Barberio, C.; Caltavuturo, L.; Fava, F.; Di Gioia, D. Genotoxicity of 4-nonylphenol and nonylphenol ethoxylate mixtures by the use of Saccharomyces cerevisiae D7 mutation assay and use of this text to evaluate the efficiency of biodegradation treatments. Ecotox. Environ. Saf. 2011, 74, 253–258.
[2]
Mota, L.C.; Barfield, C.; Hernandez, J.P.; Baldwin, W.S. Nonylphenol-mediated CYP induction is PXR-dependent: The use of humanized mice and human hepatocytes suggests that hPXR is less sensitive than mouse PXR to nonylphenol treatment. Toxicol. Appl. Pharmacol. 2011, 252, 259–267.
[3]
Kwak, H.I.; Bae, M.O.; Lee, M.H.; Lee, Y.S.; Lee, B.J.; Kang, K.S.; Chae, C.H.; Sung, H.J.; Shin, J.S.; Kim, J.H.; et al. Effects of nonylphenol, bisphenol A, and their mixture on the viviparous swordtail fish (Xiphophorus helleri). Environ. Toxicol. Chem. 2001, 20, 787–795.
[4]
Liu, X.; Tani, A.; Kimbara, K.; Kawai, F. Metabolic pathway of xenoestrogenic short ethoxy chain-nonylphenol to nonylphenol by aerobic bacteria, Ensifer sp. strain AS08 and Pseudomonas sp. strain AS90. Appl. Microbiol. Biotechnol. 2006, 72, 552–559.
[5]
De Weert, J.P.A.; Vi？as, M.; Grotenhuis, T.; Rijnaarts, H.H.M.; Langenhoff, A.A.M. Degradation of 4-n-nonylphenol under nitrate reducing conditions. Biodegradation 2011, 22, 175–187.
[6]
Casajuana, N.; Lacorte, S. New methodology for the determination of phthalate esters, bisphenol A, bisphenol A diglycidyl ether, and nonylphenol in commercial whole milk samples. J. Agric. Food Chem. 2004, 52, 3702–3707.
[7]
Wu, J.; Wang, F.; Gong, Y.; Li, D.; Sha, J.; Huang, X.; Han, X. Proteomic analysis of changes induced by nonylphenol in Sprague-Dawley rat Sertoli cells. Chem. Res. Toxicol. 2009, 22, 668–675.
[8]
Arslan, O.; Parlak, H. Embryotoxic effects of nonylphenol and octylphenol in sea urchin Arbacia lixula. Ecotoxicology 2007, 16, 439–444.
[9]
Kim, Y.J.; Yun, H.J.; Ryu, J.C. Expression profiling of estrogen responsive genes on bisphenol A, 4-nonylphenol and 17β-estradiol treatment using in house cDNA microarray. Biochip J. 2011, 5, 86–94.
[10]
Raecker, T.; Thiele, B.; Boehme, R.M.; Guenther, K. Endocrine disrupting nonyl- and octylphenol in infant food in Germany: Considerable daily intake of nonylphenol for babies. Chemosphere 2011, 82, 1533–1540.
[11]
Danzo, B.J. Environmental xenobiotics may disrupt normal endocrine function by interfering with the binding of physiological ligands to steroid receptors and binding proteins. Environ. Health. Perspect. 1997, 105, 294–301.
[12]
Kloas, W.; Lutz, I.; Einspanier, R. Amphibians as a model to study endocrine disruptors: II. Estrogenic activity of environmental chemicals in vitro and in vivo. Sci. Total Environ. 1999, 225, 59–68.
[13]
Hill, M.; Stabile, C.; Steffen, L.K.; Hill, A. Toxic effects of endocrine disrupters on freshwater sponges: Common developmental abnormalities. Environ. Pollut. 2002, 117, 295–300.
[14]
Madsen, S.S.; Skovb？lling, S.; Nielsen, C.; Korsgaard, B. 17-β Estradiol and 4-nonylphenol delay smolt development and downstream migration in Atlantic salmon. Salmo salar. Aquat. Toxicol. 2004, 68, 109–120.
[15]
Latorre, A.; Lacorte, S.; Barceló, D.; Montury, M. Determination of nonylphenol and octylphenol in paper by microwave-assisted extraction coupled to headspace solid-phase microextraction and gas chromatography-mass spectrometry. J. Chromatogr. A 2005, 1065, 251–256.
[16]
Park, J.W.; Kurosawa, S.; Aizawa, H.; Goda, Y.; Takai, M.; Ishihara, K. Piezoelectric immunosensor for bisphenol A based on signal enhancing step with 2-methacrolyloxyethyl phosphorylcholine polymeric nanoparticle. Analyst 2006, 131, 155–162.
[17]
Nú？ez, L.; Turiel, E.; Tadeo, J.L. Determination of nonylphenol and nonylphenol ethoxylates in environmental solid samples by ultrasonic-assisted extraction and high performance liquid chromatography-fluorescence detection. J. Chromatogr. A 2007, 1146, 157–163.
[18]
Céspedes, R.; Skryjová, K.; Raková, M.; Zeravik, J.; Fránek, M.; Lacorte, S.; Barceló, D. Validation of an enzyme-linked immunosorbent assay (ELISA) for the determination of 4-nonylphenol and octylphenol in surface water samples by LC-ESI-MS. Talanta 2006, 70, 745–751.
[19]
Huang, J.; Zhang, X.; Liu, S.; Lin, Q.; He, X.; Xing, X.; Lian, W.; Tang, D. Development of molecularly imprinted electrochemical sensor with titanium oxide and gold nanomaterials enhanced technique for determination of 4-nonylphenol. Sens. Actuators B Chem. 2011, 152, 292–298.
[20]
Hu, C.; Hu, S. Electrochemical characterization of cetyltrimethyl ammonium bromide modified carbon paste electrode and the application in the immobilization of DNA. Electrochim. Acta 2004, 49, 405–412.
[21]
Hu, S.; Wu, K.; Yi, H.; Cui, D. Voltammetric behavior and determination of estrogens at Nafion-modified glassy carbon electrode in the presence of cetyltrimethylammonium bromide. Anal. Chim. Acta 2002, 464, 209–216.
[22]
Lu, Q.; Hu, C.; Cui, R.; Hu, S. Direct electron transfer of hemoglobin founded on electron tunneling of CTAB monolayer. J. Phys. Chem. B 2007, 111, 9808–9813.
[23]
Yin, H.S.; Zhou, Y.L.; Ai, S.Y. Preparation and characteristic of cobalt phthalocyanine modified carbon paste electrode for bisphenol A detection. J. Electroanal. Chem. 2009, 626, 80–88.
[24]
Laviron, E. General expression of the linear potential sweep voltammogram in the case of diffusionless electrochemical systems. J. Electroanal. Chem. Interfacial Electrochem. 1979, 101, 19–28.
[25]
Kuramitz, H.; Saitoh, J.; Hattori, T.; Tanaka, S. Electrochemical removal of p-nonylphenol from dilute solutions using a carbon fiber anode. Water Res. 2002, 36, 3323–3329.
[26]
Kim, Y.S.; Katase, T.; Sekine, S.; Inoue, T.; Makino, M.; Uchiyama, T.; Fujimoto, Y.; Yamashita, N. Variation in estrogenic activity among fractions of a commercial nonylphenol by high performance liquid chromatography. Chemosphere 2004, 54, 1127–1134.
