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Paper integrated on screen printed electrode for pre-storage of reagents for environmental analysis
Author
Hee, Shee Kuan Dorcas
Supervisor
Tan, Swee Ngin
Abstract
There is widespread interest in the development of simple, rapid, and inexpensive sensors that can be applied for the detection of specific target analytes for environmental analysis. In this study, paper was chosen as the material integrated on screen-printed carbon electrodes as it is not only low-cost but it also comes with good porous structure that allows for lateral flow assay and serves as a great supporting material for developing biosensing devices. The immobilization of enzyme is an important step in the fabrication of a biosensor. Its stable and largely constant activity makes the enzyme and its immobilization an integral part of the analytical device. In the experiments, two different enzymes namely horseradish peroxidase (HRP) and acetylcholinesterase (Ach), were immobilized on the paper disc biosensor to detect hydrogen peroxide and arsenic(III) respectively.
Cyclic voltammetry (CV) experiments were used to show that the signal of the enzyme paper disc electrode was enhanced by the use of a mediator, hexacyanoferrate (II). Optimisations on applied potential and concentration of the mediator were established by the amperometric current measurement, followed by amperometric studies on effects of crosslinking by glutaraldehyde on reproducibility and shelf-life of the paper disc electrode respectively. No significant effects were observed on the enzyme biosensor showing good linear and storage stability of the biosensor.
Paper disc SPCE immobilized with acetylcholinesterase (Ach) and amperometric procedures for detecting arsenic(III), based on the inhibitive action of arsenic on acetylcholinesterase enzyme activity, have been studied. There is significant inhibition of arsenic(III) when its concentration was relatively low. This shows that the developed Ach/SPCE biosensor is sensitive in the detection of this metalloid.
It has been demonstrated that the application of paper integrated on screen-printed electrodes for pre-storage of reagents electrochemical detection for quantitative as well as qualitative microscale analysis could be done effectively for environmental analytes such as hydrogen peroxide and arsenic(III) as used in the studies.
Cyclic voltammetry (CV) experiments were used to show that the signal of the enzyme paper disc electrode was enhanced by the use of a mediator, hexacyanoferrate (II). Optimisations on applied potential and concentration of the mediator were established by the amperometric current measurement, followed by amperometric studies on effects of crosslinking by glutaraldehyde on reproducibility and shelf-life of the paper disc electrode respectively. No significant effects were observed on the enzyme biosensor showing good linear and storage stability of the biosensor.
Paper disc SPCE immobilized with acetylcholinesterase (Ach) and amperometric procedures for detecting arsenic(III), based on the inhibitive action of arsenic on acetylcholinesterase enzyme activity, have been studied. There is significant inhibition of arsenic(III) when its concentration was relatively low. This shows that the developed Ach/SPCE biosensor is sensitive in the detection of this metalloid.
It has been demonstrated that the application of paper integrated on screen-printed electrodes for pre-storage of reagents electrochemical detection for quantitative as well as qualitative microscale analysis could be done effectively for environmental analytes such as hydrogen peroxide and arsenic(III) as used in the studies.
Date Issued
2013
Call Number
R857.B54 Hee
Date Submitted
2013