International journal of multidisciplinary and current research, 2015
The thermodynamic properties of A. senegal gum, A. seyal gum (gum arabic) and A. polyacantha gum ... more The thermodynamic properties of A. senegal gum, A. seyal gum (gum arabic) and A. polyacantha gum solutions were measured and calculated. The partial specific volume of gum, partial specific volume of the solvent (water) and the volume fractions were measured and calculated. The results show that the sequences of the specific volumes of the gums under studies are in the order of decreasing molecular weight of these gums. The results of density of solid gums indicate that A. seyal molecule is more compact than A. senegal gum molecule and A. polyacantha gum molecule. The chemical potentials have been calculated from osmotic measurement for different concentrations, and then the second virial coefficients, the free energy of mixing and the gums-water interaction parameter χ were calculated. The obtained results indicate that A. polyacantha gum thermodynamically resembles A. senegal gum and they were interacting with water more than A. seyal gum.
The kinetics and the mechanism of oxidation of creatine (AA) by N-Bromosuccinimide (NBS) in an ac... more The kinetics and the mechanism of oxidation of creatine (AA) by N-Bromosuccinimide (NBS) in an acidic aqueous medium were examined under isolation conditions. Iodometric method was used to follow the unconsumed NBS at different time intervals. Mercuric(II) acetate was used as a scavenger to capture any Br- formed during the reaction and hence to avoid autocatalytic oxidation by bromine. Findings from stoichiometry measurements revealed that the reaction between AA and NBS was a 2:1 molar ratio. The kinetic study showed that the reaction was first order with respect to both AA and NBS. Increasing [H+] had a negative effect on the rate of reaction. The effect that varying the solvent composition has on the rate of reaction was investigated, and it was found that the reaction rate decreased as the dielectric constant of the solvent increased. The temperature dependence was determined under fixed experimental conditions, from which thermodynamic parameters were calculated. From the prop...
This study was carried out to determine the essential (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and ... more This study was carried out to determine the essential (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and Zn) and the toxic heavy metals (Al, As, Cd and Pb) in fruit samples of commonly consumed in Turaba District, (Saudi Arabia). Samples were digested by microwave assisted reaction system using (3:1) HNO 3 :H 2 O 2 mixture. The metals were analyzed by inductively coupled plasma-optical emission spectrometry (ICP-OES). Studied samples includes bananas ( Musa acuminata ), tomatoes ( Solanum lycopersicum ), guava ( Psidium guajava ), grapes ( Vitis spp ), date palm ( Phoenix dactylifera ), mangos ( Mangifera indica ), cantaloupe melon ( Cucumis melo ), watermelon ( Citrullus lanatus ), orange ( Citrus maxima ), mandarin ( Citrus reticulata ), lemon ( Citrus limon ) and pomegranate ( Punica Granatum ). The method was validated in terms of linearity, accuracy and precision, limit of detection (LOD) and limit of quantification (LOQ). The recovery (%) was found to be between 91.6–103.4%. It was fo...
DEDICATORIA El presente trabajo de fin de titulación está dedicado a las personas que más amo y h... more DEDICATORIA El presente trabajo de fin de titulación está dedicado a las personas que más amo y han sido mi fortaleza, guía, comprensión y apoyo. Con mucho cariño para mi esposa Jeny, mis hijos: Hayro y Sthefany, con ellos día a día luchamos, somos unidos y estamos juntos en los triunfos y fracasos. A mis hermanos y hermanas que han sido ejemplo de lucha, perseverancia y éxito. Mención especial merece mi padre que día a día me enseñó a cumplir cada una de mis metas. Desde el cielo mi madre me bendice día a día, todos mis logros se los debo a ella. Con todo mi amor te dedico a ti mamita y que Dios te tenga en la gloria. v AGRADECIMIENTO Agradezco a Dios por permitirme tener una familia maravillosa, quienes son mi soporte día a día. A mi madre porque siempre sembró en mí los buenos hábitos y me enseñó a luchar para conseguir mis objetivos. A mi padre quien con sus sabios consejos orientó mi vida en las buenas y en las malas. A mis hermanos y hermanas que me apoyaron en lo que necesitaba. Un agradecimiento especial a la
In Turabah province of Saudi Arabia, infant formula and children′s food products were investigate... more In Turabah province of Saudi Arabia, infant formula and children′s food products were investigated to determine the concentrations of essential trace elements, namely Mn, Ni, V and Si, and toxic trace elements, namely Al, Ba, Pb, Cd, and As, present in them. Their daily intake amounts were calculated and compared with provisional tolerable daily intake (PTDI), which was calculated based on the provisional tolerable weekly intake (PTWI), which was recommended by joint FAO/WHO. The results obtained were found to be below the PTDI levels. Some samples exhibited a large amount of Al. The PTWI of Si and V is not established; however, their concentrations were compared with those reported in other studies. In some samples, a high concentration of Si was observed. The method employed for evaluation was based on the limit of quantification (LOQ), limit of detection (LOD), and recovery percent of 92.3–101.6%. Accuracy and precision were employed for evaluating the results
The analytical parameters of the microwave assisted oven and of the inductively coupled plasma (I... more The analytical parameters of the microwave assisted oven and of the inductively coupled plasma (ICP) method were extensively studied and well validated in terms of spectral lines (nm), linearity (R2), accuracy (recovery %), precision (RSDs), detection and quantification limits (LODs and LOQs). The validated analytical method was used to determine the contents of selected toxic trace elements (TTEs) in fresh fruit samples from Turabah Valley of Saudi Arabia. Samples were digested by a microwave-assisted oven at the ratio of 1:2.5 (v/v) (H2O2:HNO3). The R2 > 0.9990 or better, the recovery (%) were within the acceptable range (100 ± 8), the RSDs were below 4 %, the LODs and the LOQs were ranged between 0.0005-0.0556 mg kg-1 and 0.003-0.174 mg L-1, respectively. It was found that Al, Mn, Pb, As and Cd were detected in most analyzed samples, while Co, Ni and Cr were below the detection limits of the method. A considerable variation were observed with regard to TTEs concentrations in d...
Agricultural soil and wells water that used for irrigation and drinking may contain high levels o... more Agricultural soil and wells water that used for irrigation and drinking may contain high levels of toxic trace elements. In this study the concentration of Al, Ni, Co, Mn, Cr, Pb, As and Cd in agricultural soil and wells water samples from Turabah Province (Saudi Arabia) were determined by usingI nductively coupled plasma optical emission spectrometer (ICP-OES) and microwave acid digestion techniques for soil samples. According to limit of detection (LOD) Co was not detected in all samples, while other studied trace elements (TEs) were detected in different concentrations values according to type and location of the sample. Further more, Al recorded at high values of concentration in some soil samples. The analysis method was validated in terms of accuracy, precision, limit of detection (LOD) and limit of quantification (LOQ) and confirmation reliability. The recovery percent was found to be between 91.6-103.4%.
Concentration of 12 trace elements (TEs) Na, K, Ca, Mg, Fe, Zn, B, Al, Pb, Cd, As and Sr, was det... more Concentration of 12 trace elements (TEs) Na, K, Ca, Mg, Fe, Zn, B, Al, Pb, Cd, As and Sr, was determined in drinking water of local and national factories and wells in Turabah Province (KSA) by using Inductively coupled plasma-optical emission spectrometry (ICP-OES) technique after pre-concentration and acid digestion. The results show that the concentrations of Na, K, Ca, Mg, Fe, Zn, Al, Pb, Cd and As in the samples of the local factories in Turabah Province and national factories (KSA) are below the maximum level that recommended by World Health Organization (WHO) and Saudi Arabia Standards Organization (SASO).While, the concentrations of B are above the maximum level recommended by SASO. The results of the wells samples show that the concentrations of Fe, Zn, Al, Pb, Cd and As are below the maximum level that recommended by WHO and SASO while the concentrations of Na, K, Ca, Mg and B are above and below the maximum level recommended by SASO according to the source of sample. The ...
Context: There is accumulating evidence that the metabolism of several trace elements like Cr, Cu... more Context: There is accumulating evidence that the metabolism of several trace elements like Cr, Cu, Pb, Cd, Co, Mn and Zn might have specific roles in the pathogenesis and progress of many diseases like hypertension (HTN) and diabetes mellitus (DM). Objectives: To provide a fast, efficient, sensitive, and reliable analytical procedure for trace element determination in urine samples of HTN and DM patients using inductively coupled plasma optical emission spectrometry (ICP-OES). Setting and Design: The ICP-OES operating conditions were optimised and carefully selected in order to maximise the sensitivity, precision and accuracy. Factors affecting analytical and biological variability of the concentrations under study were discussed and carefully optimised. Materials and Methods: Different digestion procedures with acids and oxidising reagents were tested. The suitable procedure ICP-OES was selected, carefully modified and applied. The validity and accuracy of the different elements were determined by spiking of samples with known amounts of multi-element standard solution. Statistical Analysis: Student t-test and analysis of variance (ANOVA) test were used for analysis. Microsoft Excel was used to assess the significance of the difference between variables. The concentrations obtained were expressed as mean value ± standard deviation (P = 0.05). Results: The results of this study showed that the mean concentrations of Cd, Zn, Pb, Cu, Cr and Mn in urine from both HTN (study group A) and DM (study group B) patients were higher than the corresponding values observed in the control group. However, while the mean value of Co was low as compared to the control group, the differences found were not significant (P = 0.05). Conclusion: The method used had excellent sensitivity, multi-element data could be obtained with very short acquisition time. The elements Cr, Cd, Pb and Zn might have specific roles in the pathogenesis and progress of HTN and DM. Further studies are required to investigate the possible roles of these elements in HTN and DM individuals.
Context: There are accumulating evidences that the metabolism of several trace elements might hav... more Context: There are accumulating evidences that the metabolism of several trace elements might have specific roles in clinical disorders and the pathogenesis of many diseases, such as diabetes mellitus (DM) and hypertension (HT). Objectives: To validate the analytical procedure and compare the levels of Cd, Cr, Cu, Pb, and Zn in scalp hair (SH) and fingernails (FN) of patients. Furthermore, to prove that human tissues such as hair and nails are useful in the studies pertaining to chronic body exposure and good biomarkers in clinical studies. Setting and Design: Inductively coupled plasma optical emission spectroscopy operating conditions were carefully selected and well-optimised in order to maximise the sensitivity for the desired elements and to obtain the best precision and accuracy. Factors affecting analytical and biological variability of the concentrations under study were discussed and carefully optimised. Materials and Methods: Totally, 160 samples of SH and 130 FN were collected from occupants of urban population from different districts adjacent to Taif city, Kingdom of Saudi Arabia. Different analytical procedures were investigated, and the most reliable one was developed and validated. Method Validity: The validity of the method was checked by standard addition method. The recoveries were in the range of 96.2-105.7%. Results: Cd, Cr, Cu, and Pb levels in SH were significantly higher in DM and HT compared to control groups, whereas, Zn was significantly lower. Cd and Pb levels in FN were significantly higher in DM and HT, whereas, Cr and Zn were lower, and Cu was in the same levels as compared to the control group. Conclusion: These findings may be consistent with those obtained in other studies, confirming that the deficiency and efficiency of trace elements play a role in clinical disorders and the pathogenesis of many diseases.
The degradation rate and kinetic parameters of carbofuran insecticide in tomato fruits were calcu... more The degradation rate and kinetic parameters of carbofuran insecticide in tomato fruits were calculated. The degradation of carbofuran was found to follow first-order reaction kinetics. The rate constants for carbofuran were 0.082 day-1 and 0.073 day-1 for the recommended application rate (10 kg feddan-1) and for the application rate used by farmers (13.5 kg feddan-1) respectively. The half-life time (t1/2) values for the recommended application rate and for the application rate used by farmers were 8.45 days and 9.50 days, respectively. The safe application time of carbofuran insecticide for the recommended application rate and for the application rate used by farmers were after 28 days and after 35 days , respectively. Spectrophotometry was employed to determine the carbofuran residues in tomato fruits, with a limit of detection (LOD) of 0.039 ppm and percent recovery in the range from 92.87 to 95.54%
International journal of multidisciplinary and current research, 2015
The thermodynamic properties of A. senegal gum, A. seyal gum (gum arabic) and A. polyacantha gum ... more The thermodynamic properties of A. senegal gum, A. seyal gum (gum arabic) and A. polyacantha gum solutions were measured and calculated. The partial specific volume of gum, partial specific volume of the solvent (water) and the volume fractions were measured and calculated. The results show that the sequences of the specific volumes of the gums under studies are in the order of decreasing molecular weight of these gums. The results of density of solid gums indicate that A. seyal molecule is more compact than A. senegal gum molecule and A. polyacantha gum molecule. The chemical potentials have been calculated from osmotic measurement for different concentrations, and then the second virial coefficients, the free energy of mixing and the gums-water interaction parameter χ were calculated. The obtained results indicate that A. polyacantha gum thermodynamically resembles A. senegal gum and they were interacting with water more than A. seyal gum.
The kinetics and the mechanism of oxidation of creatine (AA) by N-Bromosuccinimide (NBS) in an ac... more The kinetics and the mechanism of oxidation of creatine (AA) by N-Bromosuccinimide (NBS) in an acidic aqueous medium were examined under isolation conditions. Iodometric method was used to follow the unconsumed NBS at different time intervals. Mercuric(II) acetate was used as a scavenger to capture any Br- formed during the reaction and hence to avoid autocatalytic oxidation by bromine. Findings from stoichiometry measurements revealed that the reaction between AA and NBS was a 2:1 molar ratio. The kinetic study showed that the reaction was first order with respect to both AA and NBS. Increasing [H+] had a negative effect on the rate of reaction. The effect that varying the solvent composition has on the rate of reaction was investigated, and it was found that the reaction rate decreased as the dielectric constant of the solvent increased. The temperature dependence was determined under fixed experimental conditions, from which thermodynamic parameters were calculated. From the prop...
This study was carried out to determine the essential (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and ... more This study was carried out to determine the essential (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and Zn) and the toxic heavy metals (Al, As, Cd and Pb) in fruit samples of commonly consumed in Turaba District, (Saudi Arabia). Samples were digested by microwave assisted reaction system using (3:1) HNO 3 :H 2 O 2 mixture. The metals were analyzed by inductively coupled plasma-optical emission spectrometry (ICP-OES). Studied samples includes bananas ( Musa acuminata ), tomatoes ( Solanum lycopersicum ), guava ( Psidium guajava ), grapes ( Vitis spp ), date palm ( Phoenix dactylifera ), mangos ( Mangifera indica ), cantaloupe melon ( Cucumis melo ), watermelon ( Citrullus lanatus ), orange ( Citrus maxima ), mandarin ( Citrus reticulata ), lemon ( Citrus limon ) and pomegranate ( Punica Granatum ). The method was validated in terms of linearity, accuracy and precision, limit of detection (LOD) and limit of quantification (LOQ). The recovery (%) was found to be between 91.6–103.4%. It was fo...
DEDICATORIA El presente trabajo de fin de titulación está dedicado a las personas que más amo y h... more DEDICATORIA El presente trabajo de fin de titulación está dedicado a las personas que más amo y han sido mi fortaleza, guía, comprensión y apoyo. Con mucho cariño para mi esposa Jeny, mis hijos: Hayro y Sthefany, con ellos día a día luchamos, somos unidos y estamos juntos en los triunfos y fracasos. A mis hermanos y hermanas que han sido ejemplo de lucha, perseverancia y éxito. Mención especial merece mi padre que día a día me enseñó a cumplir cada una de mis metas. Desde el cielo mi madre me bendice día a día, todos mis logros se los debo a ella. Con todo mi amor te dedico a ti mamita y que Dios te tenga en la gloria. v AGRADECIMIENTO Agradezco a Dios por permitirme tener una familia maravillosa, quienes son mi soporte día a día. A mi madre porque siempre sembró en mí los buenos hábitos y me enseñó a luchar para conseguir mis objetivos. A mi padre quien con sus sabios consejos orientó mi vida en las buenas y en las malas. A mis hermanos y hermanas que me apoyaron en lo que necesitaba. Un agradecimiento especial a la
In Turabah province of Saudi Arabia, infant formula and children′s food products were investigate... more In Turabah province of Saudi Arabia, infant formula and children′s food products were investigated to determine the concentrations of essential trace elements, namely Mn, Ni, V and Si, and toxic trace elements, namely Al, Ba, Pb, Cd, and As, present in them. Their daily intake amounts were calculated and compared with provisional tolerable daily intake (PTDI), which was calculated based on the provisional tolerable weekly intake (PTWI), which was recommended by joint FAO/WHO. The results obtained were found to be below the PTDI levels. Some samples exhibited a large amount of Al. The PTWI of Si and V is not established; however, their concentrations were compared with those reported in other studies. In some samples, a high concentration of Si was observed. The method employed for evaluation was based on the limit of quantification (LOQ), limit of detection (LOD), and recovery percent of 92.3–101.6%. Accuracy and precision were employed for evaluating the results
The analytical parameters of the microwave assisted oven and of the inductively coupled plasma (I... more The analytical parameters of the microwave assisted oven and of the inductively coupled plasma (ICP) method were extensively studied and well validated in terms of spectral lines (nm), linearity (R2), accuracy (recovery %), precision (RSDs), detection and quantification limits (LODs and LOQs). The validated analytical method was used to determine the contents of selected toxic trace elements (TTEs) in fresh fruit samples from Turabah Valley of Saudi Arabia. Samples were digested by a microwave-assisted oven at the ratio of 1:2.5 (v/v) (H2O2:HNO3). The R2 > 0.9990 or better, the recovery (%) were within the acceptable range (100 ± 8), the RSDs were below 4 %, the LODs and the LOQs were ranged between 0.0005-0.0556 mg kg-1 and 0.003-0.174 mg L-1, respectively. It was found that Al, Mn, Pb, As and Cd were detected in most analyzed samples, while Co, Ni and Cr were below the detection limits of the method. A considerable variation were observed with regard to TTEs concentrations in d...
Agricultural soil and wells water that used for irrigation and drinking may contain high levels o... more Agricultural soil and wells water that used for irrigation and drinking may contain high levels of toxic trace elements. In this study the concentration of Al, Ni, Co, Mn, Cr, Pb, As and Cd in agricultural soil and wells water samples from Turabah Province (Saudi Arabia) were determined by usingI nductively coupled plasma optical emission spectrometer (ICP-OES) and microwave acid digestion techniques for soil samples. According to limit of detection (LOD) Co was not detected in all samples, while other studied trace elements (TEs) were detected in different concentrations values according to type and location of the sample. Further more, Al recorded at high values of concentration in some soil samples. The analysis method was validated in terms of accuracy, precision, limit of detection (LOD) and limit of quantification (LOQ) and confirmation reliability. The recovery percent was found to be between 91.6-103.4%.
Concentration of 12 trace elements (TEs) Na, K, Ca, Mg, Fe, Zn, B, Al, Pb, Cd, As and Sr, was det... more Concentration of 12 trace elements (TEs) Na, K, Ca, Mg, Fe, Zn, B, Al, Pb, Cd, As and Sr, was determined in drinking water of local and national factories and wells in Turabah Province (KSA) by using Inductively coupled plasma-optical emission spectrometry (ICP-OES) technique after pre-concentration and acid digestion. The results show that the concentrations of Na, K, Ca, Mg, Fe, Zn, Al, Pb, Cd and As in the samples of the local factories in Turabah Province and national factories (KSA) are below the maximum level that recommended by World Health Organization (WHO) and Saudi Arabia Standards Organization (SASO).While, the concentrations of B are above the maximum level recommended by SASO. The results of the wells samples show that the concentrations of Fe, Zn, Al, Pb, Cd and As are below the maximum level that recommended by WHO and SASO while the concentrations of Na, K, Ca, Mg and B are above and below the maximum level recommended by SASO according to the source of sample. The ...
Context: There is accumulating evidence that the metabolism of several trace elements like Cr, Cu... more Context: There is accumulating evidence that the metabolism of several trace elements like Cr, Cu, Pb, Cd, Co, Mn and Zn might have specific roles in the pathogenesis and progress of many diseases like hypertension (HTN) and diabetes mellitus (DM). Objectives: To provide a fast, efficient, sensitive, and reliable analytical procedure for trace element determination in urine samples of HTN and DM patients using inductively coupled plasma optical emission spectrometry (ICP-OES). Setting and Design: The ICP-OES operating conditions were optimised and carefully selected in order to maximise the sensitivity, precision and accuracy. Factors affecting analytical and biological variability of the concentrations under study were discussed and carefully optimised. Materials and Methods: Different digestion procedures with acids and oxidising reagents were tested. The suitable procedure ICP-OES was selected, carefully modified and applied. The validity and accuracy of the different elements were determined by spiking of samples with known amounts of multi-element standard solution. Statistical Analysis: Student t-test and analysis of variance (ANOVA) test were used for analysis. Microsoft Excel was used to assess the significance of the difference between variables. The concentrations obtained were expressed as mean value ± standard deviation (P = 0.05). Results: The results of this study showed that the mean concentrations of Cd, Zn, Pb, Cu, Cr and Mn in urine from both HTN (study group A) and DM (study group B) patients were higher than the corresponding values observed in the control group. However, while the mean value of Co was low as compared to the control group, the differences found were not significant (P = 0.05). Conclusion: The method used had excellent sensitivity, multi-element data could be obtained with very short acquisition time. The elements Cr, Cd, Pb and Zn might have specific roles in the pathogenesis and progress of HTN and DM. Further studies are required to investigate the possible roles of these elements in HTN and DM individuals.
Context: There are accumulating evidences that the metabolism of several trace elements might hav... more Context: There are accumulating evidences that the metabolism of several trace elements might have specific roles in clinical disorders and the pathogenesis of many diseases, such as diabetes mellitus (DM) and hypertension (HT). Objectives: To validate the analytical procedure and compare the levels of Cd, Cr, Cu, Pb, and Zn in scalp hair (SH) and fingernails (FN) of patients. Furthermore, to prove that human tissues such as hair and nails are useful in the studies pertaining to chronic body exposure and good biomarkers in clinical studies. Setting and Design: Inductively coupled plasma optical emission spectroscopy operating conditions were carefully selected and well-optimised in order to maximise the sensitivity for the desired elements and to obtain the best precision and accuracy. Factors affecting analytical and biological variability of the concentrations under study were discussed and carefully optimised. Materials and Methods: Totally, 160 samples of SH and 130 FN were collected from occupants of urban population from different districts adjacent to Taif city, Kingdom of Saudi Arabia. Different analytical procedures were investigated, and the most reliable one was developed and validated. Method Validity: The validity of the method was checked by standard addition method. The recoveries were in the range of 96.2-105.7%. Results: Cd, Cr, Cu, and Pb levels in SH were significantly higher in DM and HT compared to control groups, whereas, Zn was significantly lower. Cd and Pb levels in FN were significantly higher in DM and HT, whereas, Cr and Zn were lower, and Cu was in the same levels as compared to the control group. Conclusion: These findings may be consistent with those obtained in other studies, confirming that the deficiency and efficiency of trace elements play a role in clinical disorders and the pathogenesis of many diseases.
The degradation rate and kinetic parameters of carbofuran insecticide in tomato fruits were calcu... more The degradation rate and kinetic parameters of carbofuran insecticide in tomato fruits were calculated. The degradation of carbofuran was found to follow first-order reaction kinetics. The rate constants for carbofuran were 0.082 day-1 and 0.073 day-1 for the recommended application rate (10 kg feddan-1) and for the application rate used by farmers (13.5 kg feddan-1) respectively. The half-life time (t1/2) values for the recommended application rate and for the application rate used by farmers were 8.45 days and 9.50 days, respectively. The safe application time of carbofuran insecticide for the recommended application rate and for the application rate used by farmers were after 28 days and after 35 days , respectively. Spectrophotometry was employed to determine the carbofuran residues in tomato fruits, with a limit of detection (LOD) of 0.039 ppm and percent recovery in the range from 92.87 to 95.54%
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