Abstract
A study on the electrochemical aptasensing of Cd(II) on a screen printed carbon electrode (SPCE) modified with carbon black (CB) and gold nanoparticles (AuNPs) is reported. The nano-platform was prepared by drop casting CB and electrodepositing AuNPs by cycling potential from −400 mV to 1100 mV at 50 mVs−1 scan rate. The immobilized 36-base thiolated ssDNA aptamer on the SPCE-CB-AuNPs, upon interaction with Cd(II), underwent a conformational change that resulted in change in electrochemical current response. After the optimization of incubation time and aptamer concentration at 30 min and 2 μM, respectively, the aptasensor detected Cd(II) in the linear range of 1–50 ppb with a limit of detection of 0.14 ppb using square wave voltammetry (SWV). The aptasensor was applied in real water sample analysis and the results were validated with inductively coupled plasma-optimal emission spectroscope (ICP-OES). The aptasensor demonstrated good reproducibility, acceptable stability and excellent selectivity towards Cd(II), endorsing potential application in environmental monitoring of Cd(II).
Original language | English |
---|---|
Article number | 113796 |
Journal | Journal of Electroanalytical Chemistry |
Volume | 858 |
DOIs | |
Publication status | Published - 1 Feb 2020 |
Keywords
- Biosensor, aptamer
- Cadmium
- Carbon black
- Electrochemical aptasensor
- Gold nanoparticles
ASJC Scopus subject areas
- Analytical Chemistry
- General Chemical Engineering
- Electrochemistry