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Stevia contains natural compounds that are plant herbs that estimated to be 150–400 times sweeter than saccharide. The study included the effect of different concentrations, different pH in present, and without a present ascorbic acid solution. A potentiostat was used as a cyclic voltammetric technique by a modified glassy carbon electrode (GCE) with multiwall carbon nanotubes (MWCNT) as a nanosensor (MWCNT/GCE) to enhance the oxidation-reduction current peaks of stevia compound in blood medium. The oxidation current peak of stevia appeared at 0.028 gm/ml. The study has been found the safety dose used before oxidation of the blood components from the appearing of oxidation current peak of stevia which characterized at -600 mV. Alkaline blood medium in the presence of ascorbic acid acted as an anti-oxidative reagent with present ascorbic acid by enhanced the reduction current peak at -500 mV, so, stevia compound can be used as a safe sweetener alternative of saccharide.

The helicobacter-pylori (H.pylori) bacteria that infects the digestive system is one of the bacteria that is intractable in routine treatments with antibiotics, as it has been studied using nano-antibiotics studied by the electrochemical behavior of three Nano antibiotics. The study aims to identify the extent of the effect of micro-antibiotics on the composition of the blood serum medium by electrochemical analysis using the cyclic voltammetric method and to compare it with nano-antibiotics. Three Nano-antibiotics such as Amoxicillin NPs, Azithromycin NPs, and Metronidazole NPs, and the mixture of the three nanoparticles as Nano-Kit were investigated in blood serum medium utilizing cyclic voltammetry methods by a glass carbonic electrode (GCE). The three nanoparticles in antibiotics were prepared by converting the micro antibiotic with a lyophilizer technique and characterization by field emission scanning electron microscopy (FESEM) with all antibiotics in Nano size. The results showed that all Nano compounds act as an antioxidant antibiotic in the blood serum medium. The study also included the electrochemical characterization of the Nano-kit of the mixture for the three Nano-biotics to prove anti-oxidative stress. It was found that the three nano-biotics have reduced current peaks without any oxidation peaks. The three nano-antibiotics can be an excellent treatment to eradicate H. pylori infection permanently. Therefore, the results of this research can be adapted to use the nano-kit of the mixture in the appropriate treatment of H.pylori infection.

Ketamine (KN) and xylazine (XZ) are one of the famous anesthesias using for the animal. The electrochemical properties of the KN and XZ compounds in the rbbit blood samples were studied by cyclic voltammetric (CV) technique using glassy carbon electrode (GCE). The study was included different concentrations, pH, scan rates, interferences between them (KN and XZ) and reliability (stability). The oxidation-reduction current peaks was studied of the KN and XZ alone and both (mixed) in the blood medium to determine the effect of these compounds on the blood components. It was found the oxidation- reduction current peaks for mixed of KN and XZ in blood medium at 0.1 and -0.8 V respectively, and the oxidation peak was enhanced in acidic pH (3), while the reduction peaks was enhanced in alkaline pH (8). Also, the mixing of KN and XZ in blood medium was acted to decrease the oxidation peak and enhance the reduction peak, so it can be said that mixing is best to work in the animal state.

In this study, a grafted polymer (GP) with ZnO nanoparticles (GP/ZnO NPs) was attached on the surface of glassy carbon electrode (GCE), in order to produce a new modified electrode (GP/ZnO NPs-GCE). The gamma irradiation method was used to grafted polystyrene (polymer) with acrylonitrile (monomer), while slow evaporation process was used to prepare the new modified electrode. The cyclic voltammetry (CV) of K4[Fe(CN)6] was used to study the electrochemical properties GP/ZnO NPs-GCE. The peak separation (ΔEpa-c) was 500 mV between the redox peaks of Fe(II)/Fe(III) in an aqueous solution of 1 M KCl and the current ratio of redox current peaks (Ipa/Ipc) was ≈ 1 for the modified electrode. This indicated that the modified electrode has s good reversibility and conductivity, wherefore; it was applied in the voltammetric filed. It was found that the modified electrode GP/ZnO NPs-GCE have a reasonable solubility and stability at various pH medium. Additionally, the sensitivity of the electrochemical analysis by cyclic voltammetric (CV) method is extensively subjected to the pH medium and the scan rate (SR). A couple of redox current peaks of K4[Fe(CN)6] in KCl solution was observed with a reversible process: Fe3+/Fe2+. Finally a good diffusion coefficient of electroactive species (D) for the new modified electrode was found in this study by chronoamperometry method using Cottrell equation.

The cyclic voltammetric electrochemical technique was utilized to investigate the effect of different temperatures on the redox current peaks of rifampicin (RF), a drug commonly used to treat many diseases including tuberculosis (TB), in vitro for human blood medium. A modified working electrode of glassy carbon electrode (GCE) with carbon nanotube (CNT) (CNT / GCE) was used as a sensitive nano-sensor to evaluate the impact of temperature on the blood medium in the presence of RF ions. The results confirmed the presence of two oxidation and one reduction current peaks of RF in blood medium at 0.5, 1, and -0.5 V respectively. The redox current peaks of RF ions in blood medium were enhanced with increasing the temperature from 20 to 36oC. The activation energy (E*) values were determined by applying Arrhenius equation with oxidative and anti-oxidative peaks of Ea*(Ipa)= 9.252 and 11.026 kJ.mol-1.K-1,respectively. Other thermodynamic functions such as the change in each of activation Enthalpy (ΔH*), activation Gibbs energy (ΔG*) and activation Entropy (ΔS*) values were estimated using Eyring equation. The present results of the effects of different temperatures on the blood status in presence of RF lead to the explanation of the oxidative stress of the drug which used in an inflammatory of blood at different temperature.

The cyclic voltammetric electrochemical technique was utilized to investigate the effect of different temperatures on the redox current peaks of rifampicin (RF), a drug commonly used to treat many diseases including tuberculosis (TB), in vitro for human blood medium. A modified working electrode of glassy carbon electrode (GCE) with carbon nanotube (CNT) (CNT / GCE) was used as a sensitive nano-sensor to evaluate the impact of temperature on the blood medium in the presence of RF ions. The results confirmed the presence of two oxidation and one reduction current peaks of RF in blood medium at 0.5, 1, and -0.5 V respectively. The redox current peaks of RF ions in blood medium were enhanced with increasing the temperature from 20 to 36oC. The activation energy (E*) values were determined by applying Arrhenius equation with oxidative and anti-oxidative peaks of Ea*(Ipa)= 9.252 and 11.026 kJ.mol-1.K-1,respectively. Other thermodynamic functions such as the change in each of activation Enthalpy (ΔH*), activation Gibbs energy (ΔG*) and activation Entropy (ΔS*) values were estimated using Eyring equation. The present results of the effects of different temperatures on the blood status in presence of RF lead to the explanation of the oxidative stress of the drug which used in an inflammatory of blood at different temperature.

The glassy carbon electrode (GCE) was modified with multiwalled carbon nanotube (MWCNT) and graphene (MWCNT/GCE), (graphene/GCE) to study the electrochemical behaviour of paracetamol using cyclic voltammetric technique at different paracetamol particles size (186μm, 4-9μm, 45nm) in a 10 ml solution of (1M) KCl and (0.1mM) paracetamol at scan rate (0.1 V/s). The results of cyclic voltammogram showed the anodic current peaks of paracetamol increases with decrease particle size. Also, the solubility is enhancement with decreasing particle size. MWCNT/GCE is a good biosensor with high electrochemical sensitivity for paracetamol than graphene/GCE.

The oxidation–reduction of nicotinic acid was studied in 0.1 M potassium chloride on a grafted polymer electrode (GPE) (the materials of GPE are polystyrene grafted with acrylonitrile as a monomer using gamma irradiation) during cyclic voltammetric technique. The oxidation–reduction potential peaks of nicotinic acid appear at −0.425 and −0.525 V on GPE versus Ag/AgCl, respectively. The redox current peaks of nicotinic acid at GPE were enhanced in comparison with the bar glassy carbon electrode. Hence, GPE can be used as working electrode for voltammetric analysis of nicotinic acid at different scan rates, pH, concentrations and temperatures. The redox current of nicotinic acid using GPE was largely influenced by concentration, pH, temperature and scan rate. Based on the obtained calibration curve, a linear graph of up to 0.1 mM nicotinic acid, with an impressive sensitivity response of R 2 = 0.902, was obtained. Based on chronoamperometric and chronocoulometric technique, a diffusion coefficient for nicotinic acid at GPE was determined.

Oxidation–reduction of mercury ions in 0.1 M KCl was studied by cyclic voltammetry at a grafted polymer electrode (GPE) prepared from polystyrene grafted with acrylonitrile as monomer by use of gamma irradiation. The oxidation potential peaks of mercury at the GPE appear at +0.3 and +0.15 V versus Ag/AgCl as reference electrode; the reduction potential peak appears at 0.0 V. The redox current peaks of Hg(II) were enhanced approximately tenfold in comparison with those at a glassy carbon electrode. Hence, GPE can be used for voltammetric analysis of Hg(II). The redox current of Hg(II) using the GPE was strongly affected by concentration and scan rate. A linear (R 2 = 0.952) calibration plot was obtained up to 0.1 mM Hg(II), with a highly sensitive response. When chronocoulometry and chronoamperometry were used to study 3 mM Hg2+ in 0.1 M KCl, using the GPE as working electrode, the diffusion coefficient (D) was 2.2 × 10−7 cm2/s and the total charge transferred to the GPE as Hg ions was 15.4 μC/m2.

A grafted polymer reference electrode (GPRE) (polystyrene grafted with acrylonitrile as a monomer using gamma irradiation) was fabricated as a reference electrode using cyclic voltammetry (CV). The redox process of K3Fe(CN)6 during CV was studied. It was found that the redox current peaks of Fe(II)/Fe(III) in 0.1 M of KCl as supporting electrolyte is given the same oxidation–reduction current as in the Ag/AgCl reference electrode, indicating a good result of GPRE and, hence, it can be used for voltammetric analysis technique. The physical properties of GPRE include good hardness, insoluble in non-aqueous electrolytes (except dimethyl formamide and chloroform), and good stability at different solvents. In addition, the sensitivity under conditions of CV is significantly dependent on the scan rate (SR) and variation in concentration. At different SRs, redox peaks of K3Fe(CN)6 were observed in a reversible process: Fe(II)/Fe(III). Interestingly, the redox reaction of Fe(II)/Fe(III) solution using GCE versus GPRE remains constant even after 15 cyclings. It is therefore evident that the GPRE possesses some degree of stability. Also, the new reference electrode GPRE has improved the properties of electroanalysis of CV on the working electrode GCE in reliability with the relative standard deviation.

A new grafted polymer electrode (GPE) (polystyrene as polymer) was grafted with acrylonitrile as a monomer using gamma irradiation to produce a new grafted polymer. The redox process of K3Fe(CN)6 during cyclic voltammetry was studied by the new GPE. The ratio of Ipc/Ipa >1 of GPE to GCE Ipc/Ipa = 1.7, indicating that this electrode is a reversible electrode and can be used in conductivity studies by voltammetric analysis. The physical properties of the new electrode GP have good hardness, insolubility, and stability at different high temperatures and at different pH. Also, the sensitivity under conditions of cyclic voltammetry is significantly dependent on pH, electrolyte, and scan rate. At different scan rates, two oxidation peaks and two reduction peaks of Fe(III) were observed in a reversible process: Fe(III) Fe(II), and Fe(II) Fe(0). Interestingly, the redox reaction of Fe(III) solution using GPE remained constant even after 15 cycles. It is therefore evident that the GPE possesses some degree of stability. The potential use of the grafted polymer as a useful electrode material is therefore clearly evident.

Frying oils were studied by Fourier-transform infrared (FT-IR) spectroscopy, in the range 4,000–200 cm−1, at different temperatures, in the liquid and solid states. The infrared spectrum at 15 °C was similar to that at 200 °C. The band at 730 cm−1 which was assigned to the rocking mode of (–CH2) disappeared at higher temperature because of the rotational isomerism which occurred in the oil structure. The activation energy (E a) of the disappearing (–CH2) band, calculated by use of the chemical dynamic method using the Arrhenius equation, is 8.45 kJ mol−1. The enthalpy difference (ΔH) between the two rotational isomer bands of the conformational structures of the oil at 730 and 1,790 cm−1, at different high temperatures, was also calculated, by use of the Van’t Hoff equation; the value obtained was −10.85 kJ mol−1.

Problem statement: Glassy carbon electrode GCE was modified with different microparticles to increase the efficiency of analysis Mn2+ in blood samples by cyclic voltammetry and applied for the detection of trace Mn(II) by oxidation process. Approach: The structure and composition of the modified GCE processed by using Carbon Nanotubes CNT and C60 to produce two modified electrodes CNT/GCE and C60/GCE, to detect a trace Mn2+ by cyclic voltammetry for mouse blood with comparison the best modified electrode for detection the ion by the sensitivity and values of Relative Standard Deviation (RSD) in calibration curve. Results: A wide linear range and good repeatability were obtained for Mn2+ detection by CNT/GCE in aqueous KCl as supporting electrolyte at different ratio of KCl: Blood using CNT/GCE and C60/GCE, the relative standard deviation of two modified electrodes are good on CNT/GCE than C60/GCE. Conclusion: The two modified electrodes CNT/GCE and C60/GCE depending on the redox current of Mn(II) ions were evaluated by the determination of low concentration of Mn(II) in blood samples by cyclic voltammetric method, the most modified electrode to detect the Mn(II) in blood is CNT/GCE.

Polystyrene grafted with acrylonitrile using gamma-irradiation technique was successfully synthesized. This process was carried out at various gamma dose (0.2-1.5 Mrad). The new grafted polymer was characterized and its properties were investigated. The results indicate that best grafting percentage ratio could be revealed when the concentration of the catalyst Ferrous Ammonium Sulphate (FAS) is about 2% and the monomer concentration is 90%, at 1.25 Mrad dose. The new grafted polymer was proved by FTIR, TGA and Viscosity techniques, which was analyzed and studied with a suggested presented mechanism. The adding of acrylonitrile to polystyrene improved the physical properties of polystyrene

A glassy carbon electrode (GCE) was modified with a grafted polymer GP film (polystyrene grafted with acrylonitrile as a monomer using gamma irradiation) using a solution evaporation method to produce a new modified electrode GP/GCE. The redox process of K3[Fe(CN)6] during cyclic voltammetry was studied using the GP/GCE. It was found that the peak separation (ΔEpa-c) between the redox peaks of ferricyanide ion in an aqueous solution is 82 mV and the current ratio of redox peaks, (Ipa/Ipc), is 1 for the GP/GCE, indicating good reversibility with good conductivity of the modified electrode. Hence, it can be used for voltammetric analysis. The physical properties of the modified electrode GP/GCE include good hardness, high adhesion to the metal surfaces of electrode collectors, solubility and good stability of the GP on GCE at different pH levels. Also, the sensitivity under conditions of cyclic voltammetry is significantly dependent on the pH, the electrolyte used and the scan rate. At different scan rates, two oxidation peaks and two reduction peaks of Fe(III) were observed in a reversible process: Fe(III)/Fe(II) and Fe(II)/Fe(0).

Lead ion of sulfate was studied electrochemically analysis, using cyclic voltammetric technique by glassy carbon electrode (GCE) in normal saline solution (0.9%NaCl). The results of the study have been found oxidation and reduction current peaks of lead ion in normal saline at -550 mV and -650mV respectively. It was studied the electrochemical properties of the redox current peaks of Pb(II) with different reagents such as glucose, uric acid, urea and ascorbic acid in normal saline. The redox current peaks of Pb(II) were enhanced through using each of glucose, uric acid and urea, but in ascorbic acid the reduction current peak was reduced. Also, the other phenomena of the reduction current peak of Pb(II) was disappeared when using blood as an electrolyte because the lead ions act as oxidant pollutant in blood medium.

The study of Sodium Saccharin (NaSc), this one of the chemical compounds was used as a replacement for natural sugar, which taking by diabetic patients. NaSc was studied by cyclic voltammetric technique to analysis at different temperature using modified glassy carbon electrode (GCE) with carbon nanotubes (CNT) as working electrode (CNT/GCE). Activation energy (Ea*) of NaSc was studied in 1M Na2SO4 as an electrolyte at different temperature using Arrhenius equation at both GCE and CNT/GCE. Other thermodynamic parameters such as activation free energy (∆G*), activation enthalpy (∆H*) and activation entropy (∆S*) were determined at both GCE and CNT/GCE using Eyring equation. Other thermodynamic parameters such as the values of entropy for cathodic current peak of NaSc on GCE and CNT/GCE are positive value, this means that the reaction is spontaneous reversible, but the negative values of entropy is irreversible reaction.

Electrochemical studies by cyclic voltammetric (CV) method provide high potential for investigation of oxidant pollutant compounds such as Pb(II). Glassy carbon electrode (GCE) can be used for the potentiostatic analysis of the lead ions in different electrolyte especially human blood medium to studying the effect of the lead ions on the blood components. The results of this study were found that oxidation and reduction current peaks of lead ions in 1M KCl is high value and enhanced by adding ascorbic acid (AA) solution, while in human blood medium was disappearing the reduction current peak and enhance the oxidation current peak by lead ions. It means that lead ions in blood medium act as an oxidative reagent and causes problem in the decomposition of the blood component. Also, it was found that using folic acid (FA) solution with lead ions in blood medium causes the enhancement of reduction current peaks of lead ion and decreasing for oxidation current peaks, so this means that folic acid solution acts as antioxidative reagent in present of lead ions in blood medium, it may recommended to taking tablet of FA for the patients who suffers to lead pollution.

Acrylonitrile was successfully grafted on polystyrene modified with activated carbon using gamma-irradiation technique. This process was carried out modified at various gamma dose (0.2 to 1.5 Mrad). The new grafted polymer (GP) was characterized and its properties were investigated. In this study, it was found that 2 g of polystyrene, 90% (w/w) acrylonitrile monomer, 2% (w/w) ferrous ammonium sulfate (FAS) catalyst, 1 mg activated carbon powder and 1.25 Mrad gamma dose are the optimized conditions required for the polymerization of GP.The grafted polymer was proved by Fourier transform infrared (FTIR), thermo gravimetric analysis (TGA) and UV-visible spectroscopy. A mechanism is presented to explain the formation of GP. Key words: Activated carbon, polystyrene, acrylonitrile, gamma-irradiation, ferrous ammonium sulfate (FAS)

Infrared spectral data are reported in the region 4000-200 cm −1 for salicylaldehyde (S. A.), methylsalicylate (M.S.) and ethylsalicylate (E.S.) in the solid, liquid and vapour phases. They indicate that these compounds exist as equilibrium mixtures of conformers through rotations around two or three axes with HO- cis and HO- trans as major ones in the case of M.S. and E.S. and as the only pair in the case of S.A. Vibrational frequency assignment of the fundamental and non-fundamental modes are made. Determination of Δ H values have been carried out and are used as a measure of the relative stabilities of the conformers in each system. In the vapour and liquid phases the HO- cis conformer was found to be the most stable one.