title: Highly selective and sensitive simple sensor based on electrochemically treated nano polypyrrole-sodium dodecyl sulphate film for the detection of para-nitrophenol.
abstract: An ultrasensitive and highly selective electrochemical sensor for the determination of p-nitrophenol (p-NP) was developed based on electrochemically treated nano polypyrrole/sodium dodecyl sulphate film (ENPPy/SDS film) modified glassy carbon electrode. The nano polypyrrole/sodium dodecyl sulphate film (NPPy/SDS film) was prepared and treated electrochemically in phosphate buffer solution. The surface morphology and elemental analysis of treated and untreated NPPy/SDS film were characterized by FESEM and EDX analysis, respectively. Wettability of polymer films were analysed by contact angle test. The hydrophilic nature of the polymer film decreased after electrochemical treatment. Effect of the pH of electrolyte and thickness of the ENPPy/SDS film on determination of p-NP was optimised by cyclic voltammetry. Under the optimised conditions, the p-NP was determined from the oxidation peak of p-hydroxyaminophenol which was formed from the reduction of p-NP in the reduction segment of cyclic voltammetry. A very good linear detection range (from 0.1 nM to 100 μM) and the best LOD (0.1 nM) were obtained for p-NP with very good selectivity. This detection limit is below to the allowed limit in drinking water, 0.43 μM, proposed by the U.S. Environmental Protection Agency (EPA) and earlier reports. Moreover, ENPPy/SDS film based sensor exhibits high sensitivity (4.4546 μA μM(-1)) to p-NP. Experimental results show that it is a fast and simple sensor for p-NP.
authors.affiliation: Alagappa University, Karaikudi, Tamil Nadu, 630 003, India.
authors.forename: Abraham Daniel
authors.initials: AD
authors.lastname: Arulraj
authors.affiliation: Central Electrochemical Research Institute, Karaikudi, 630 006, India.
authors.forename: Muthunanthevar
authors.initials: M
authors.lastname: Vijayan
authors.affiliation: Department of Natural Products Chemistry, Madurai Kamaraj University, Palkalai Nagar, Madurai, 625 021, India. Electronic address: sivarunjan@gmail.com.
authors.forename: Vairathevar Sivasamy
authors.initials: VS
authors.lastname: Vasantha
mesh_terms: D055664:Electrochemical Techniques / Q000379:methods*; D057230:Limit of Detection; D008855:Microscopy, Electron, Scanning; D009596:Nitrophenols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry*; D017155:Wettability
chemical_list: D009596:Nitrophenols; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D012967:Sodium Dodecyl Sulfate; C024836:4-nitrophenol
keywords: Contact angle test; Electrochemical sensor; Square wave voltammetry; p-Nitrophenol