A pencil-lead bismuth film electrode and chemometric tools for simultaneous determination of heavy metals in propolis samples

2016 ◽  
Vol 125 ◽  
pp. 266-272 ◽  
Author(s):  
Gastón D. Pierini ◽  
Marcelo F. Pistonesi ◽  
María S. Di Nezio ◽  
María E. Centurión
2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Karen C. Bedin ◽  
Edson Y. Mitsuyasu ◽  
Amanda Ronix ◽  
André L. Cazetta ◽  
Osvaldo Pezoti ◽  
...  

The present work reports the development and application of bismuth-film electrode (BiFE), obtained by in situ method on the pencil-lead graphite surface, for simultaneous Cd(II) and Pb(II) determination at trace levels, as alternative to replace the mercury-film electrodes. Experimental factors, deposition time (td), deposition potential (Ed), and Bi(III) concentration (CBi), were investigated by applying a 23 factorial design using 0.10 mol/L acetate buffer solution (pH 4.5) as supporting electrolyte. The analysis conditions of the differential pulse technique were td = 250 s, Ed = -1.40 V, and CBi = 250 mg L−1. The validation of the method employing BiFE was accomplished by determination of merit figures. The detection limits were of 11.0 μg L−1 for Cd(II) and 11.5 μg L−1 for Pb(II), confirming that proposed method is attractive and suitable for heavy metals determination. Additionally, the BiFE developed was successfully applied for the Cd(II) and Pb(II) determination in wastewater sample of battery industry.


Author(s):  
Hao Zhang ◽  
Jun Cui ◽  
Yuxin Zeng ◽  
Yu Zhang ◽  
Yuansheng Pei

Abstract A sensitive, selective, and stable sensor for the simultaneous determination of Cd2+ and Pb2+ in aqueous solution has been developed based on the carbon dots (CDs) and Nafion-modified bismuth film glassy carbon electrode (GCE). High graphitized CDs prepared by the sulfuric acid-assisted hydrothermal synthesis were directly electrodeposited on the GCE surface by cyclic voltammetry. Compared with the conventional bismuth film electrodes, CDs greatly improved the electrochemical activity of the bismuth film electrode for the detection of Cd2+ and Pb2+. After decorating CDs, the surface impedance of the GCE was decreased from 10.9 kΩ to 4.84 kΩ. Meanwhile, the corresponding response currents of the Bi/GCE were increased over 7.4 and 2.4 times for Cd2+ and Pb2+ with a wide linear range of 0.05-0.50 mg/L, respectively. High sensitivity was obtained with the detection limits of 3.1 μg L-1 (Cd2+) and 2.3 μg L-1 (Pb2+). Moreover, good stability was obtained for the simultaneous determination of Cd2+ and Pb2+ in the practical underground water with the relative standard deviations less than 10%. The results indicated that the CDs-modified bismuth film electrode could potentially be applied to detect the heavy metal ion concentrations in practical environment.


Sign in / Sign up

Export Citation Format

Share Document