الفهرس 
Nanomaterials: An overviewOnly 14 pages are availabe for public view
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Abstract
Electrochemistry has many features making it a unique
technique for choice when analyzing real sample.
Electrochemical techniques have the advantages of low
cost, instrumental simplicity and portability in addition to
high sensitivity and selectivity as well as wide linear
range with low detection limits. This makes
electroanalytical techniques among the most favorable
analytical methods for different applications.
In particular, voltammetric sensors are an important
category of electrochemical sensors. This thesis describes
the development and electrochemical characterization and
analytical applications of two voltammetric sensors
developed for dopamine (DA) and glucose detection.
Nickel nanoparticles (Ni-NP) based sensors and nickelcopper
nanoparticles (Ni/CuNPs) based sensors were
developed for the selective detection of dopamine and
glucose, respectively.
This thesis is divided into three chapters. A brief
description of each chapter is given below:
Chapter I: this chapter provides a general overview for
nanomaterials, classification of nanomaterials, important
tools to characterize nanomaterials and applications of
nanoscience in electrochemistry. In addition, this chapter
includes a general introduction on various
electroanalytical techniques. Moreover, this chapter
describes the different types of chemical sensors and
discusses in detail voltammetric sensors, and the
important concepts of voltammetric methods relevant to
the thesis work.Chapter II: This chapter represents the fabrication of
nickel nanoparticles based sensor for the selective
determination of dopamine. The composition and the
electrochemical behavior of the developed nano nickel
modified glassy carbon electrode (nano-Ni-nafion/GCE)
and nano nickel modified graphite electrode (nano-Ninafion/
GE)were investigated by field emission scanning
electron microscope (FESEM),X-ray diffraction
spectroscopy (XRD),cyclic voltammetry(CV) and
differential pulse voltammetry (DPV). The results
indicated the formation of stable nano-Ni nafion film on
the surface of glassy carbon and graphite electrodes. The
developed sensor was shown to have excellent
electrocatalytic activity, excellent reproducibility and
stability towards the oxidation of dopamine. Different
parameters affecting the analytical performance of the
developed sensors were investigated, including: number
of cycles, concentration of NaOH, concentration of NiSO4
and scan rate. Under optimized conditions, the response of
the prepared modified electrodes towards dopamine was
found to be linear in the concentration range 1-2000
Ppmwith a detection limit of 1.62 μM (nano-Ninafion/
GCE) and 0.29μM (nano-Ni-nafion/GE). DA
sensors exhibited a sensitivity of 13.8, 61.3 mA L-1mol for
nano-Ni-nafion/GCE and nano-Ni-nafion/GE,
respectively.
Chapter III: This chapter deals with the development
of nickel copper nanoparticles based sensor for the
glucose. The composition and the electrochemical
behavior of the developed nano nickel-copper modified
glassy carbon electrode (nano-Ni/Cu GCE) were
investigated by field emission scanning electron
microscope (EFSEM), energy dispersive X-ray spectrometer (EDX), cyclic voltammetry (CV) and
differential pulse voltammetry (DPV).
The results indicated the formation of high quality and
stable nano Ni-Cu film on the surface of glass carbon
(GC) electrode. This nano Ni-Cu sensor could effectively
oxidize glucose with high catalytic activity compared to
only Ni or Cu films. Different parameters affecting the
analytical performance of the developed nano Ni-Cu
sensor were investigated, including: copper concentration,
nickel concentration and number of cycles. Under
optimized conditions, the response of the prepared
modified electrode towards glucose was found to be linear
in the concentration range (0.25 to 30 mM) with a
sensitivity of 20.78μAmol−1L) and low detection limit
(30μM). The sensor was utilized for the analysis of
glucose in blood serum sample and the results obtained
were correlated to those observed using the commercial
glucose sensor.