Sensitive detection of endocrine disrupters using ionic liquid – Single walled carbon nanotubes modified screen-printed based biosensors

• Published in: Talanta (Oxford) Vol. 85; no. 4; pp. 2007 - 2013
• Main Authors: Gurban, Ana-Maria, Rotariu, Lucian, Baibarac, Mihaela, Baltog, Ioan, Bala, Camelia
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30.09.2011; Elsevier
• Subjects: Alkylphenols; Analytical chemistry; Biological and medical sciences; Biosensing Techniques - methods; Biosensors; Biotechnology; Chemistry; Dielectric Spectroscopy; Electrochemistry; Electrodes; Endocrine Disruptors - analysis; Endocrine Disruptors - chemistry; Enzyme; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General, instrumentation; Imidazoles - chemistry; Ionic liquid; Ionic Liquids - chemistry; Methods. Procedures. Technologies; Nanotubes, Carbon - chemistry; Phenols - analysis; Phenols - chemistry; Printing; Screen-printed electrode; Single-walled carbon nanotubes; Spectrometric and optical methods; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman; Various methods and equipments; Screen-printed electrode; Enzyme; Single-walled carbon nanotubes; Alkylphenols; Ionic liquid; Fourier transform spectroscopy; Hydrogen peroxide; Stability; Carbon nanotubes; Chemical sensor; Infrared spectrometry; Electrocatalysis; Reduction; Sensitivity; Response time; Biosensor; Detection limit; Nanocomposite; Raman spectrometry; Detection; Electrochemical impedance spectroscopy
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2011.07.045

Simple and low cost biosensor based on screen-printed electrode for sensitive detection of some alkylphenols was developed, by entrapment of HRP in a nanocomposite gel based on single-walled carbon nanotubes (SWCNTs) and 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) ionic liquid. Raman and FTIR spectroscopy, CV and EIS studies demonstrate the interaction between SWCNTs and ionic liquid. The nanocomposite gel, SWCNT–[BMIM][PF6] provides to the modified sensor a considerable enhanced electrocatalytic activity toward hydrogen peroxide reduction. The HRP based biosensor exhibits high sensitivity and good stability, allowing a detection of the alkylphenols at an applied potential of −0.2V vs. Ag/AgCl, in linear range from 5.5 to 97.7μM for 4-t-octylphenol and respectively, between 5.5 and 140μM for 4-n-nonylphenol, with a response time of about 5s. The detection limit was 1.1μM for 4-t-octylphenol, and respectively 0.4μM for 4-n-nonylphenol (S/N=3).