Development of electrochemical immunosensor-based poly(3,4-ethylenedioxythiophene) composites for clenbuterol detection
Illegal usage of banned antibiotic such as clenbuterol (CLB) in food products is a big concern since this will directly affect the consumer health. World Health Organization (WHO) is forbidding any usage of CLB in the livestock animals due to health effects such as muscular tremor, increase ra...
Saved in:
| Main Author: | |
|---|---|
| Format: | Thesis |
| Language: | English |
| Published: |
2018
|
| Subjects: | |
| Online Access: | http://psasir.upm.edu.my/id/eprint/76916/1/ITMA%202018%2019%20-%20IR.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Illegal usage of banned antibiotic such as clenbuterol (CLB) in food products is a
big concern since this will directly affect the consumer health. World Health
Organization (WHO) is forbidding any usage of CLB in the livestock animals due
to health effects such as muscular tremor, increase rate of heart throb,
glaucoma, fever and respiratory problems to human that influenced by CLB
residue in food products. Currently, the methods used for CLB detection is
expensive, time-consuming and involving complicated analysis. In this study,
immunosensor modified with poly(3,4-ethylenedioxythiophene)/multi-walled
carbon nanotube (PEDOT/MWCNT), poly(3,4-ethylenedioxythiophene)/graphene
oxide (PEDOT/GO) and anti-clenbuterol antibody (Ab) were developed on
screen-printed carbon electrode (SPCE) for detection of CLB. Sensor platforms
from modification of electrode with PEDOT/MWCNT and PEDOT/GO composites
were prepared by electropolymerization using chronoamperometry (CA)
technique. The operating conditions (concentration of MWCNT, concentration of
GO, electropolymerization potential and deposition time) were optimized by
using response surface methodology (RSM) combined with central composite
design (CCD) and Box-Behnken design (BBD) for PEDOT/MWCNT and
PEDOT/GO composites, respectively to obtain the optimum peak current. The
statistical analysis showed that the concentration of MWCNT, concentration of
GO, electropolymerization potential and deposition time have significantly
affected the peak current response. The coefficient of determination (R2) for
model equations of PEDOT/MWCNT and PEDOT/GO composites resulting value
of 0.9973 and 0.9965, respectively. The optimized condition predicted by the
software was compared with the experiments and resulting in less than 2% error,
indicating that this model was reliable and able to predict the peak current
response accurately. The cyclic voltammetry (CV) measurements indicated that
PEDOT/MWCNT and PEDOT/GO modified electrodes had successfully
enhanced the peak currents compared to PEDOT, MWCNT and GO.
Incorporation of MWCNT and GO into PEDOT were proven by field emission
scanning electron microscopy (FESEM) images, Fourier transform infrared (FTIR) and Raman spectra. The optimized PEDOT/MWCNT and PEDOT/GO
composites were further modified with Ab on SPCE to develop CLB
immunosensors. Detection of CLB was performed through direct competitive
format, whereby the CLB in sample solutions were competing with CLB
conjugated with horseradish peroxide (CLB-HRP) to bind with Ab. The change in
current value was analyzed through CA for quantification of CLB amount in the
sample. The immunoassay conditions for these immunosensors were optimized
by using RSM/CCD, whereby the incubation temperature, Ag incubation time
and %blocking were determined as significant parameters. The resulting
immunosensors exhibited excellent reproducibility with low standard deviation
(SD) value. These immunosensors also very selective towards CLB in
comparison with other antibiotics from same family group (β-agonist) and
another group of antibiotics. Based on storage stability study, these
immunosensors can retain its performance up to 95% after a month storage at 4
°C. Thus, highly reproducible, sensitive and stable immunosensors for detection
of CLB in the real samples were developed and satisfactorily meet the
requirement for actual application. |
|---|