| نویسندگان | اسمائ خوبی-سید مهدی قریشی-محسن بهپور-سعید معصوم |
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| نشریه | ANAL CHEM |
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| تاریخ انتشار | ۲۰۱۴-۱-۰۱ |
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| نمایه نشریه | ISI |
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چکیده مقاله
Multivariate curve resolution by alternating least-squares (MCR-ALS)
was used for voltammetric determination of dopamine (DA) in the presence of
epinephrine (EP) at a gold nanoparticles chemically modified carbon paste electrode
(AuNPs/CPE). Scanning electron microscopy (SEM), electrochemical impedance
spectroscopy (EIS), and cyclic voltammetry (CV) techniques were applied for
characterization of the nanostructure modified electrode. Central composite rotatable
design (CCRD) was employed to generate an experimental program to offer data to
model the effects of different parameters on voltammetric responses. Response surface
methodology (RSM) was applied to show the individual and interactive effects of
chemical and instrumental variables at five levels, combined according to CCRD. For
determination of DA in the presence of unexpected interference, three-way data were
achieved from various pulse heights in differential pulse voltammetry (DPV) technique.
This type of data construction, analyzed by MCR-ALS, makes it possible to exploit the
so-called “second-order advantage”. The second-order advantage provided unbiased results even in the presence of electroactive
interferences with highly overlapped peaks. Also, an algorithm was applied to correct the detected potential shift in the
voltammetric data. The voltammograms of the samples were then deposited in an augmented data matrix (column-wise) and
subsequently analyzed by MCR-ALS. The effect of rotational ambiguity associated with a particular MCR-ALS solution under a
set of constraints was also studied. The proposed method could be applied for the determination of DA and EP in the presence
of each other in a wide concentration range of 0.1−205.0 μM, and the detection limit of DA has been found to be 35.5 nM.
Finally, the technique has been used for the reliable analysis of DA in real samples.