الفهرس 
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Abstract
Nimesulide:
The electrochemical behavior of nimesulide was studied in B.R.
buffer solutions of different pH values. It showed in reduction process at DC polarography two waves unequal in height within the range from 1.5
to 9.8 pH this waves correspond to reduction of (O-N=O) group.
The half wave potential is pH dependent, that means El/2 shifted to more
negative as the pH increase. The logarithmic analysis of the
polarographic wave referred to irreversible reduction process, the effect
of mercury height on it referred to the process is controlled by diffusion
with a little adsorption.
The cyclic voltammetric behavior of nimesulide is detected at the
glassy carbon electrode in B.R. buffer pH (2.0-7.0), the obtained
voltammograms showed one cathodic peak in acidic and neutral and
vanishes at alkaline medium the peak potential shifted to more negative
as pH increase, the plotting of ip vs. square root of scan rate gave linear
relation deviating from the origin this means the process controlled by
diffusion and little adsorption, The kinetic parameters are calculated.
The linear sweep technique was applied to study and optimize the
’experimental arid instrumentalconditions, and thisoptimization remitS--
were pH-5.30, deposition potential = -o.4V, deposition time =60 S., scan
rate =500 mV/s. and step height =5 mY.
The calibration curve (i, vs. concentration) give linear relation from 8
xlO-6 to 4 xlO·7 M. detection limit was 2.8 xl O” M.
Secnidazole:
The electrochemical behavior of secnidazole was studied in B.R.
buffer solutions of different pH values. It showed in reduction process at
1
Summary
DC polarography two waves unequal in height within the pH range from
1.5 to 9.8 these waves according to reduction of (O-N 0) group.
The half wave potential is pH dependent, that means E1I2 shifted to more
negative as the pH increased. The logarithmic analysis of the
polarographic wave referred to the reduction process irreversible, the
effect of mercury height on it referred to the process _controlled by
diffusion with a little adsorption.
The cyclic voltammetric behavior of secnidazole is detected at the
glassy carbon electrode in B.R. buffer pH (:3.10-10.0), the obtained
voltammograms showed one cathodic peak in acidic and neutral -and
vanishes at alkaline medium the peak potential shifted to more negative
as pH increase, the plotting of ip vs. square root of scan rate gave linear
relation deviating from the origin this means the process controlled by
diffusion and little adsorption. The kinetic parameters are calculated.
The linear sweep technique was applied to study and optimize the
experimental and instrumental conditions, and this optimization results
were pH=5.30, deposition potential = -0.2 V, deposition time =30 s., scan
rate =500mV/s. and step height =20 mY.
The calibration curve (i, vs. concentration) gives linear relation from 1
xlO-4to 6xl0-6 M, detection limit was 1.7 xl0-61\~.
• __ .” . _~ ~ T_ .... _._.- _.- ... _- .~.. - - __ . __ ... _._0 _ nifuroxazide:
The electrochemical behavior of nifuroxazide was studied in B.R.
buffer solutions of different pH values. It showed in reduction process at
DC polarography two waves unequal in height within the range from 2.71
to 11.0 pH this waves according to reduction of (O-N=O) and (C N)
groups.
The half wave potential is pH dependent, that means E1/2 shifted to more
negative as the pH increase the logarithmic analysis of the polarographic
ii
- ---- --- ----- - --------
Summary
wave referred to the reduction process irreversible, the effect of mercury
height on it referred to the process controlled by diffusion with a little
adsorption.
The cyclic voltammetric behavior of nifuroxazide is detected at the
glassy carbon electrode in B.R. buffer pH (2.71-11.0), the obtained
voltammograms showed one cathodic peak in acidic and neutral and
vanishes at alkaline medium the peak potential shifted to more negative
as pH increases. The plotting of ip vs. square root of scan rate gave linear
relation deviating from the origin this means the:process is controlled by
diffusion and little adsorption. The kinetic parameters are calculated.
The linear sweep technique was applied to study and optimize the
experimental and instrumental conditions, and this optimization results
were pH 8.18, deposition potential = -0.4 V, deposition time =60 s., scan
rate =500 mY/so and step height =5 mY.
The calibration curve (i, vs. concentration) gives linear relation from 2
xl O” to 4 xl0-7 M. detection limit was 6.5 xl0-8 1\1.
Tinidazole:
The electrochemical behavior of tinidazole was studied in B.R.
buffer solutions of different pH values. It showed in reduction process at
DC polarography two waves unequal in height within thetafigeI’rofil2”.03
to 10.55 pH this waves according to reduction of (O-N=O) group.
The half wave potential is pH dependent, that means EI/2 shifted to more
negative as the pH increase the logarithmic analysis of the polarographic
wave referred to the reduction process irreversible, the effect of mercury
height on i) referred to the process controlled by diffusion with a little
adsorption.
The cyclic voltammetric behavior of tinidazole is detected at the
glassy carbon electrode in B.R. buffer pH (3.20-8.78), the obtained
iii
Sum,,”,ry
voltammograms showed one cathodic peak in acidic and neutral and
vanishes at alkaline medium the peak potential shifted to more negative
as pH increase, the plotting of ip vs. square root of scan rate gave linear
relation deviating from the origin this means the process controlled by
diffusion and little adsorption. The kinetic parameters are calculated.
The linear sweep technique was applied to study and optimize the
experimental and instrumental conditions, and this optimization results
were pH=6.13, deposition potential = -O.4V,deposition time =30 s., scan
rate =500 mV/s. and step height =10 mV.
The calibration curve (i, vs. concentration) give linear relation from I
xlO-sto IxIO-6M. detection limit was 2.6 x10-7M .
cinnarizine:
The electrochemical behavior of cinnarizine was studied in B.R.
buffer solutions of different pH values. It showed in reduction process at
DC polarography two waves unequal in height within the range from 1.5
to 9.50 pH this waves according to reduction of (C=C) group.
The half wave potential is pH dependent, this means E1I2 is shifted to
more negative as the pH increase the logarithmic analysis of the
polarographic wave referred to the reduction process irreversible, the
effect of mercury height on irreferred to the process controlled by
diffusion with a little adsorption.
The cyclic voltammetric behavior of cinnarizine is detected at the
glassy carbon electrode in B.R. buffer pH (3.67-8.80), the obtained
voltammograms showed one cathodic peak in acidic and neutral and
vanishes at alkaline medium the peak potential shifted to more negative
. as pH increase, the plotting of ip vs. square root of scan rate gave linear
relation deviating from the origin this means the process controlled by
diffusion and little adsorption. The kinetic parameters are calculated.
oj
IV
--- Summary
The linear sweep technique was applied to study and optimize the
experimental and instrumental conditions, and this optimization results
were pH 2.54, deposition potential = O.OV~deposition time =60 s., scan
rate =500 mY/so and step height =10 mY.
The .calibration curve (i, vs. concentration) give linear relation from 1
xlO-6 to 2xlO·7 M. And detection limit was 9 xlO·9 M.
\
chlorodiazepoxide:
The electrochemical behavior of chlorodiazepoxide was studied
in B.R .. buffer solutions of different pH values. It showed in reduction
process at DC polarography two waves unequal in height within the range
from 1.5 to 9.8 pH this waves according to reduction of (N-O) and (C N)
groups.
The half wave potential is pH dependent, that means E1n shifted to more
negative as the pH increase the logarithmic analysis of the polarographic
wave referred to the reduction process irreversible, the effect of mercury
height on i1 referred to the process controlled by diffusion with alittle
adsorption.
The cyclic voltammetric behavior of chlorodiazepoxide is detected
at the glassy carbon electrode in B.R. buffer pH (2.15-10.45), the
obtained voltammograms showed two cathodic peak in acidic and one
cathodic peak at neutral and alkaline medium the peak potential shifted to
more negative as pH increase, the plotting of ill vs, square root of scan
rate gave linear relation deviating from the origin this means the process
controlled by diffusion and little adsorption. The kinetic parameters are
. calculated.
The linear sweep technique was applied to study and optimize the
experimental and instrumental conditions, and this optimization results
v •
Summary
were pH=4.14, deposition potential = -OAV,deposition time = 30 s., scan rate =500 mV/s. and step height =10 mV and at pH==7.33,deposition time = -OAV,deposition time = 30sec., scan rate =500 mY/sec. and stepbeight=10mV.The calibration curve (i, vs. concentration) give linear relation from
5 xl0-6 to 2xlO·7M at pH= 4.14 and lxl0-4 to IxlO-ciM at pH= 7.33.
And detection limit was 5 xlO·8 M at pH=4.14 and 2.5 xIO·7