Pub Date : 2016-07-28DOI: 10.4172/2155-9872.1000327
Fadwa Benkessou, Ibrahim El Serafi, Brigitte Twelkmeyer, M. Abedi‐Valugerdi, Moustapha Hassan
N,N-Dimethylacetamide (DMA) is an excellent solvent that is highly used in the production of synthetic fibres as well as in the pharmaceutical industry. It is present as a solvent in the intravenous formulation of busulphan, a drug used in high doses as myeloablative treatment prior to hematopoietic stem cell transplantation (SCT). DMA was shown to cause hepatotoxicity as well as neurotoxicity, as revealed throughout several studies including phase I study. In the present investigation we developed an LC-MS based method to detect and quantify DMA and its primary metabolite N-monomethylacetamide (MMA) simultaneously in human plasma, using a C-18 ODS-AQ/S-5 µm 12 nm separation column. The lower limits of quantification (LLOQs) for DMA and MMA were 1.8 µM and 8.6 µM, respectively. The limit of detection (LOD) for DMA and MMA were 0.53 µM and 2.52 µM, respectively. The recovery of DMA from plasma ranged from 97-101% and for MMA from 76-100%. The stability for DMA and MMA was assessed through freeze-thaw cycles and storage at different temperatures (RT, 4°C and -20°C for three days); the results have shown <7.9% CV for DMA and <14.1% for MMA. The inter-day and intra-day variation assay accuracy and precision was <6.3% for DMA and <8.6% for MMA. The calibration was linear within the ranges 1 to 4000 µM. The method was applied to follow the kinetics and to quantify DMA and its metabolite MMA in 49 plasma samples from 2 patients undergoing SCT and treated with intravenous busulphan that contain DMA. The present method is simple, robust and showed good selectivity with high accuracy, precision and reproducibility. Moreover, it can be utilized to determine DMA and its metabolite in workers, patients and environment and hence avoid toxic exposure.
{"title":"Quantification of Dimethylacetamide and its Primary Metabolite Monomethylacetamide in Plasma Using Robust LC-MS Method","authors":"Fadwa Benkessou, Ibrahim El Serafi, Brigitte Twelkmeyer, M. Abedi‐Valugerdi, Moustapha Hassan","doi":"10.4172/2155-9872.1000327","DOIUrl":"https://doi.org/10.4172/2155-9872.1000327","url":null,"abstract":"N,N-Dimethylacetamide (DMA) is an excellent solvent that is highly used in the production of synthetic fibres as well as in the pharmaceutical industry. It is present as a solvent in the intravenous formulation of busulphan, a drug used in high doses as myeloablative treatment prior to hematopoietic stem cell transplantation (SCT). DMA was shown to cause hepatotoxicity as well as neurotoxicity, as revealed throughout several studies including phase I study. In the present investigation we developed an LC-MS based method to detect and quantify DMA and its primary metabolite N-monomethylacetamide (MMA) simultaneously in human plasma, using a C-18 ODS-AQ/S-5 µm 12 nm separation column. The lower limits of quantification (LLOQs) for DMA and MMA were 1.8 µM and 8.6 µM, respectively. The limit of detection (LOD) for DMA and MMA were 0.53 µM and 2.52 µM, respectively. The recovery of DMA from plasma ranged from 97-101% and for MMA from 76-100%. The stability for DMA and MMA was assessed through freeze-thaw cycles and storage at different temperatures (RT, 4°C and -20°C for three days); the results have shown <7.9% CV for DMA and <14.1% for MMA. The inter-day and intra-day variation assay accuracy and precision was <6.3% for DMA and <8.6% for MMA. The calibration was linear within the ranges 1 to 4000 µM. The method was applied to follow the kinetics and to quantify DMA and its metabolite MMA in 49 plasma samples from 2 patients undergoing SCT and treated with intravenous busulphan that contain DMA. The present method is simple, robust and showed good selectivity with high accuracy, precision and reproducibility. Moreover, it can be utilized to determine DMA and its metabolite in workers, patients and environment and hence avoid toxic exposure.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88844364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-07-26DOI: 10.4172/2155-9872.1000325
A. MagdaAkl, M. MagdyBekheit, I. Helmy
In the present study, a cloud point extraction method was used for the preconcentration and extraction of cadmium (II) and zinc (II) ions in different environmental samples. The zinc and cadmium ions formed hydrophobic complexes with phenanthraquinone monophenyl thiosemicarbazone (PPT). These complexes were extracted using Triton X-114 nonionic surfactant. The surfactant-rich phase was diluted with acidified methanol. Then, the concentrations of the metal ions were determined by FAAS. The experimental factors controlling the process of separation are investigated e.g., pH, complexing agent concentration, surfactant's concentration, temperature, and incubation time. The present CPE-FAAS procedure has been used to preconcentrate and determine Cd(II) and Zn(II) metal ions in natural water samples, drug samples and certified reference materials. The LODs for cadmium(II) and zinc(II) ions were 0.38 and 1.85 μg/L, respectively with a preconcentration factor of 100. The recovery % of the extracted Cd(II) and Zn(II), is greater than 90% and the relative standard deviation(RSD,%) is less than 5%.
{"title":"Application of CPE-FAAS Methodology for the Analysis of Trace Heavy Metals in Real Samples using Phenanthraquinone Monophenyl Thiosemicarbazone and Triton X-114","authors":"A. MagdaAkl, M. MagdyBekheit, I. Helmy","doi":"10.4172/2155-9872.1000325","DOIUrl":"https://doi.org/10.4172/2155-9872.1000325","url":null,"abstract":"In the present study, a cloud point extraction method was used for the preconcentration and extraction of cadmium (II) and zinc (II) ions in different environmental samples. The zinc and cadmium ions formed hydrophobic complexes with phenanthraquinone monophenyl thiosemicarbazone (PPT). These complexes were extracted using Triton X-114 nonionic surfactant. The surfactant-rich phase was diluted with acidified methanol. Then, the concentrations of the metal ions were determined by FAAS. The experimental factors controlling the process of separation are investigated e.g., pH, complexing agent concentration, surfactant's concentration, temperature, and incubation time. The present CPE-FAAS procedure has been used to preconcentrate and determine Cd(II) and Zn(II) metal ions in natural water samples, drug samples and certified reference materials. The LODs for cadmium(II) and zinc(II) ions were 0.38 and 1.85 μg/L, respectively with a preconcentration factor of 100. The recovery % of the extracted Cd(II) and Zn(II), is greater than 90% and the relative standard deviation(RSD,%) is less than 5%.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88776093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-07-15DOI: 10.4172/2155-9872.1000328
T. Balusamy, T. Nishimura
The in-situ local corrosion behavior of scratched epoxy coated carbon steel is investigated in sat. Ca(OH)2 with varying concentration of Cl- ions by localized electrochemical impedance spectroscopy (LEIS). The localized corrosion process and mechanism of coated steel (scratch area) is measured by LEIS plots and 3D topographic images. The LEIS responses measured at the defect are attributed to the pore impedance with defect in the highfrequency range and an interfacial corrosion reaction in the low-frequency range of corroding steel at the base of defect within 1-10 h immersion. The continuous decrease in |Z| at the scratch is due to the higher extent of dissolution of Fe with increase of Cl- ion concentration. However, the resistance values of coated steel in sat. Ca(OH)2 with each concentration of Cl- ions are not changed significantly with increase in immersion time from 1-10 h. On the other hand, LEIS Nyquist plots clearly showed that the measured impedance at high frequency is related to corrosion products formed at the defect which acts as anodic zones and the low frequency part are related to corroding of carbon steel with immersion of 1-5 days. 2D topographic images clearly showed that corrosion occurs at scratch and followed by coating degradation at scratch front as well as away from scratch due to cathodic reactions (reduction of O2) leads to coating delamination. No significant change in corrosion resistance is observed for 0 and 0.0085 M/L of Cl- ions containing solution for 5 days of immersion as well as 1-10 h immersion. This is due the formation of better passive film on the steel surface (defect) in which the competition between the aggressive Cl- ions and the inhibitive OH- ions determines the rate of corrosion. A significant decrease in corrosion resistance is observed with higher concentration of Cl- ions (0.17 and 0.51 M) due to the preferential adsorption of Cl- ions at the defect site.
{"title":"Localized Electrochemical Impedance Spectroscopy Observation on Scratched Epoxy Coated Carbon Steel in Saturated Ca(OH)2 with Various Chloride Concentration","authors":"T. Balusamy, T. Nishimura","doi":"10.4172/2155-9872.1000328","DOIUrl":"https://doi.org/10.4172/2155-9872.1000328","url":null,"abstract":"The in-situ local corrosion behavior of scratched epoxy coated carbon steel is investigated in sat. Ca(OH)2 with varying concentration of Cl- ions by localized electrochemical impedance spectroscopy (LEIS). The localized corrosion process and mechanism of coated steel (scratch area) is measured by LEIS plots and 3D topographic images. The LEIS responses measured at the defect are attributed to the pore impedance with defect in the highfrequency range and an interfacial corrosion reaction in the low-frequency range of corroding steel at the base of defect within 1-10 h immersion. The continuous decrease in |Z| at the scratch is due to the higher extent of dissolution of Fe with increase of Cl- ion concentration. However, the resistance values of coated steel in sat. Ca(OH)2 with each concentration of Cl- ions are not changed significantly with increase in immersion time from 1-10 h. On the other hand, LEIS Nyquist plots clearly showed that the measured impedance at high frequency is related to corrosion products formed at the defect which acts as anodic zones and the low frequency part are related to corroding of carbon steel with immersion of 1-5 days. 2D topographic images clearly showed that corrosion occurs at scratch and followed by coating degradation at scratch front as well as away from scratch due to cathodic reactions (reduction of O2) leads to coating delamination. No significant change in corrosion resistance is observed for 0 and 0.0085 M/L of Cl- ions containing solution for 5 days of immersion as well as 1-10 h immersion. This is due the formation of better passive film on the steel surface (defect) in which the competition between the aggressive Cl- ions and the inhibitive OH- ions determines the rate of corrosion. A significant decrease in corrosion resistance is observed with higher concentration of Cl- ions (0.17 and 0.51 M) due to the preferential adsorption of Cl- ions at the defect site.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75183831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-07-01DOI: 10.4172/2155-9872.1000326
S. Patnaik, P. C. Mishra, Nayak Rn, Anil Kumar Giri
In this study highly efficient sorbent, chitosan-Fe3+ complex with high chemical stability material was synthesized and the performance towards Fluoride adsorption was evaluated by batch experiments. The adsorption process reached equilibrium at 1 hour. The maximum adsorption capacity reached 2.34 mg/g of F- at an initial concentration of 50 mg/L of F- and adsorbent dosage of 10 g/L. Moreover, no significant change in the fluoride removal efficiency was observed in the pH range of 3.0-10.0. The adverse influence of sulphate on fluoride removal was the most significant, followed by bicarbonate and nitrate, whereas chloride had slightly adverse effect. Adsorption process followed the pseudo-second-order kinetic model, and the experimental equilibrium data were fitted well with the Langmuir-Freundlich and D-R isotherm models. Thermodynamic parameters revealed that fluoride adsorption was a spontaneous and exothermic process. The chitosan-Fe3+ complex could be effectively regenerated by NaCl solution.
{"title":"Removal of Fluoride from Aqueous Solution Using Chitosan-Iron Complex","authors":"S. Patnaik, P. C. Mishra, Nayak Rn, Anil Kumar Giri","doi":"10.4172/2155-9872.1000326","DOIUrl":"https://doi.org/10.4172/2155-9872.1000326","url":null,"abstract":"In this study highly efficient sorbent, chitosan-Fe3+ complex with high chemical stability material was synthesized and the performance towards Fluoride adsorption was evaluated by batch experiments. The adsorption process reached equilibrium at 1 hour. The maximum adsorption capacity reached 2.34 mg/g of F- at an initial concentration of 50 mg/L of F- and adsorbent dosage of 10 g/L. Moreover, no significant change in the fluoride removal efficiency was observed in the pH range of 3.0-10.0. The adverse influence of sulphate on fluoride removal was the most significant, followed by bicarbonate and nitrate, whereas chloride had slightly adverse effect. Adsorption process followed the pseudo-second-order kinetic model, and the experimental equilibrium data were fitted well with the Langmuir-Freundlich and D-R isotherm models. Thermodynamic parameters revealed that fluoride adsorption was a spontaneous and exothermic process. The chitosan-Fe3+ complex could be effectively regenerated by NaCl solution.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77570834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-06-27DOI: 10.4172/2155-9872.1000323
J. PeterBaugh
This review covers the principles of two dimensional gas and liquid chromatography (2DGC and 2DLC) and briefly introduces the theory accounting for the increase in separation resulting from a greater peak capacity than for the one dimensional (1D) mode. The advance in the techniques from multi-dimensional to comprehensive chromatography is discussed. The more recent development of multi-dimensional chromatography ion mobility mass spectrometry receives a mention to highlight the added dimension of molecular size and shape (molecular collision cross section) as an enabling tool for increasing component separation and peak capacity. Although both the techniques of 2DGC and LC are described the focus is on the environmental and food applications of 2DGC, principally when coupled to mass spectrometry, with TOFMS and HRMS as prime examples.
{"title":"Advances and Changes in the Techniques of Multi- Dimensional and Comprehensive Chromatography and When Coupled with Mass Spectrometry","authors":"J. PeterBaugh","doi":"10.4172/2155-9872.1000323","DOIUrl":"https://doi.org/10.4172/2155-9872.1000323","url":null,"abstract":"This review covers the principles of two dimensional gas and liquid chromatography (2DGC and 2DLC) and briefly introduces the theory accounting for the increase in separation resulting from a greater peak capacity than for the one dimensional (1D) mode. The advance in the techniques from multi-dimensional to comprehensive chromatography is discussed. The more recent development of multi-dimensional chromatography ion mobility mass spectrometry receives a mention to highlight the added dimension of molecular size and shape (molecular collision cross section) as an enabling tool for increasing component separation and peak capacity. Although both the techniques of 2DGC and LC are described the focus is on the environmental and food applications of 2DGC, principally when coupled to mass spectrometry, with TOFMS and HRMS as prime examples.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"294 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83439017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-06-27DOI: 10.4172/2155-9872.1000324
K. Arrhenius, J. Engelbrektsson, Haleh Yaghooby
Terpenes have been shown to be the dominant VOCs present in biogas mostly in plants where food wastes are digested. In particular, p-cymene and D-limonene have been reported to represent up to 90% of all VOCs in the biogas. A number of problems have been linked to terpenes in biogas plants, including odor problems, indoor air quality issues at workplaces and operational problems. In order to study the faith of terpenes, there is a need to develop robust analytical methods to quantify terpenes in all the flows at biogas plants including substrates, gas, and water samples. In this study, reliable analytical methods for the detection and quantification of terpenes in these flows are presented. The methods have a common final step consisting of a TD-GC-MS/FID analysis using Tenax TA for the trapping of terpenes. The methods were then applied to some samples taken at a biogas plant where food waste is digested. The results show that D-limonene was the dominant terpene in the substrate whereas p-cymene was dominant in biogas and process water.
{"title":"Development of Analytical Methods to Gain Insight into the Role of Terpenesin Biogas Plants","authors":"K. Arrhenius, J. Engelbrektsson, Haleh Yaghooby","doi":"10.4172/2155-9872.1000324","DOIUrl":"https://doi.org/10.4172/2155-9872.1000324","url":null,"abstract":"Terpenes have been shown to be the dominant VOCs present in biogas mostly in plants where food wastes are digested. In particular, p-cymene and D-limonene have been reported to represent up to 90% of all VOCs in the biogas. A number of problems have been linked to terpenes in biogas plants, including odor problems, indoor air quality issues at workplaces and operational problems. In order to study the faith of terpenes, there is a need to develop robust analytical methods to quantify terpenes in all the flows at biogas plants including substrates, gas, and water samples. In this study, reliable analytical methods for the detection and quantification of terpenes in these flows are presented. The methods have a common final step consisting of a TD-GC-MS/FID analysis using Tenax TA for the trapping of terpenes. The methods were then applied to some samples taken at a biogas plant where food waste is digested. The results show that D-limonene was the dominant terpene in the substrate whereas p-cymene was dominant in biogas and process water.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"176 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75521998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-06-17DOI: 10.4172/2155-9872.1000322
K. Alizadeh, Nasim Abbasi Rad
A new highly selective optical sensor was prepared by de-esterification of triacetyl cellulose transparent film and chemical immobilization of 1-acenaphthoquinone 1-thiosemicarbazone (L) on it. The absorbance variation of immobilized 1-acenaphthoquinone 1-thiosemicarbazone on hydrolyzed cellulose acetate film of upon addition of 1.5 × 10-5 mol L-1 aqueous solutions of Zn2+, Pb2+, K+, Cu2+, Ag+, Ni2 , Cd2+, Ca2+, CrO4 2-, Hg2+, Co2+, Mn2+, Cr3+, S2 O3 2-, Mg2+, Na+, Al3+, Tl+ and Fe3+ indicated a substantiality much larger variation for the Nickel ion in compare to other studied ions. Consequently, the new hydrazone derivative L possesses a high selectivity towards this metal ion. Influences of various experimental parameters on Ni2+ sensing, including the reaction time, the solution pH and the concentration of reagents were studied. A linear relationship was observed between the variance in membrane absorbance(âA) at 337 nm and Ni2+ concentrations in a range from 5.01 × 10-10 to 2.04 × 10-5 mol L-1 with a detection limit (3σ) of 1.00 × 10-10 mol L-1. No significant interference from 100 times concentrations of a number of potentially interfering ions was detected for the nickel ion determination. The sensor showed a good durability and short response time with no evidence of reagent leaching. The optical sensor was successfully applied to the determination of nickel in real water samples.
{"title":"A New Optical Sensor for Selective Monitoring of Nickel Ion Based on A Hydrazone Derivative Immobilized on the Triacetyl Cellulose Membrane","authors":"K. Alizadeh, Nasim Abbasi Rad","doi":"10.4172/2155-9872.1000322","DOIUrl":"https://doi.org/10.4172/2155-9872.1000322","url":null,"abstract":"A new highly selective optical sensor was prepared by de-esterification of triacetyl cellulose transparent film and chemical immobilization of 1-acenaphthoquinone 1-thiosemicarbazone (L) on it. The absorbance variation of immobilized 1-acenaphthoquinone 1-thiosemicarbazone on hydrolyzed cellulose acetate film of upon addition of 1.5 × 10-5 mol L-1 aqueous solutions of Zn2+, Pb2+, K+, Cu2+, Ag+, Ni2 , Cd2+, Ca2+, CrO4 2-, Hg2+, Co2+, Mn2+, Cr3+, S2 O3 2-, Mg2+, Na+, Al3+, Tl+ and Fe3+ indicated a substantiality much larger variation for the Nickel ion in compare to other studied ions. Consequently, the new hydrazone derivative L possesses a high selectivity towards this metal ion. Influences of various experimental parameters on Ni2+ sensing, including the reaction time, the solution pH and the concentration of reagents were studied. A linear relationship was observed between the variance in membrane absorbance(âA) at 337 nm and Ni2+ concentrations in a range from 5.01 × 10-10 to 2.04 × 10-5 mol L-1 with a detection limit (3σ) of 1.00 × 10-10 mol L-1. No significant interference from 100 times concentrations of a number of potentially interfering ions was detected for the nickel ion determination. The sensor showed a good durability and short response time with no evidence of reagent leaching. The optical sensor was successfully applied to the determination of nickel in real water samples.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"106 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79251091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-05-23DOI: 10.4172/2155-9872.1000321
B. Liszka, A. Lenferink, C. Otto
The growth of single, self- nucleated calcium carbonate crystals on a polysulfone (PSU) film was investigated with high resolution, time lapse Raman imaging. The Raman images were acquired on the interface of the polymer with the crystal. The growth of crystals could thus be followed in time. PSU is a polymer that is used as a membrane material in water cleaning technology. The intensity of the Raman band at the position of 1086 cm-1, which is due to the symmetric stretching of the C-O bonds in the carbonate group of calcite was used to translate the number of CO3 2- ions in a crystal to the growth in time. The growth rate of single crystals of calcium carbonate on a surface was obtained from successive Raman images. We are presenting for the first time time-lapse Raman images of single crystal growth as a direct method to determine a crystal growth rate on an industrially relevant membrane material, like polysulfone.
{"title":"Growth Rate and Morphology of a Single Calcium Carbonate Crystal on Polysulfone Film Measured with Time Lapse Raman Micro Spectroscopy","authors":"B. Liszka, A. Lenferink, C. Otto","doi":"10.4172/2155-9872.1000321","DOIUrl":"https://doi.org/10.4172/2155-9872.1000321","url":null,"abstract":"The growth of single, self- nucleated calcium carbonate crystals on a polysulfone (PSU) film was investigated with high resolution, time lapse Raman imaging. The Raman images were acquired on the interface of the polymer with the crystal. The growth of crystals could thus be followed in time. PSU is a polymer that is used as a membrane material in water cleaning technology. The intensity of the Raman band at the position of 1086 cm-1, which is due to the symmetric stretching of the C-O bonds in the carbonate group of calcite was used to translate the number of CO3 2- ions in a crystal to the growth in time. The growth rate of single crystals of calcium carbonate on a surface was obtained from successive Raman images. We are presenting for the first time time-lapse Raman images of single crystal growth as a direct method to determine a crystal growth rate on an industrially relevant membrane material, like polysulfone.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"15 1","pages":"321"},"PeriodicalIF":0.0,"publicationDate":"2016-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84412906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-05-02DOI: 10.4172/2155-9872.1000320
Mukasa-Teb, eke Iz, Wasajja-Teb, H. Eke, A. Schumann, F. Lugolobi
The search for natural clays that can be used to provide industrial bleaching earths is worldwide; Uganda’s rich volcanic clays from North Eastern region remain unutilized. The aim of the study was to evaluate the use and efficiency of clay mined locally at Kangole to bleach vegetable oils when activated by leaching in hydrochloric and sulfuric acids of varying concentrations. The effectiveness of raw and acid activated clays developed from local Ugandan clay from Kangole, Moroto District of North Eastern Uganda for bleaching cotton and sunflower seed oil was studied. Hydrochloric and sulfuric acid of varying strengths 0, 10, 20 and 30% was used for the activation. Mixture of the degummed, neutralized oil and appropriate clay powders placed in Pyrex glass flasks, fitted with a magnetic stirrer was placed in an iso-electric mantle thermostated at 90°C in a nitrogen atmosphere for a duration ranging from 10 to 60 minutes before being cooled and filtered to record absorbance. Minerals were identified using IR, XRD, and elemental chemical composition of fusion mixture following Hutchinson’s method. The clay was montmorillonite in character with subordinate Kaolinite and Illite and unaltered tuff in form plagioclase and feldspars. Samples were subjected to hydrochloric and sulfuric acid activation with 10, 20 and 30% acid at 105°C. Bleaching efficiency for cotton and sunflower oils were. Study revealed that maximum decrease in absorbance of bleached oil was attained with clay leached in 30% sulfuric acid when the oil was in contact with clay for 30 to 40 minute at 90°C. Results obtained in which the performance of locally prepared clays was expressed in terms of percentage decrease in absorbance of oil showed that, the acid-activated samples were more effective in the bleaching of oils than raw clay. The percentage decrease in absorbance of sunflower oil of 80% was achieved with clay leached in 20% hydrochloric acid. Yet cotton oil attained highest percentage absorbance of 55% during the bleaching step. This study revealed for the first time the use Kangole clay in bleaching oils. It’s the first time the clay minerals in admixture mined at Kangole has been shown to contain montmorillonite, illite, kaolinite, feldspars and plagioclase which contribute to its bleaching activity.
{"title":"Bleaching Edible Oils Using Clay from Kangole, Moroto District, North Eastern Uganda","authors":"Mukasa-Teb, eke Iz, Wasajja-Teb, H. Eke, A. Schumann, F. Lugolobi","doi":"10.4172/2155-9872.1000320","DOIUrl":"https://doi.org/10.4172/2155-9872.1000320","url":null,"abstract":"The search for natural clays that can be used to provide industrial bleaching earths is worldwide; Uganda’s rich volcanic clays from North Eastern region remain unutilized. The aim of the study was to evaluate the use and efficiency of clay mined locally at Kangole to bleach vegetable oils when activated by leaching in hydrochloric and sulfuric acids of varying concentrations. The effectiveness of raw and acid activated clays developed from local Ugandan clay from Kangole, Moroto District of North Eastern Uganda for bleaching cotton and sunflower seed oil was studied. Hydrochloric and sulfuric acid of varying strengths 0, 10, 20 and 30% was used for the activation. Mixture of the degummed, neutralized oil and appropriate clay powders placed in Pyrex glass flasks, fitted with a magnetic stirrer was placed in an iso-electric mantle thermostated at 90°C in a nitrogen atmosphere for a duration ranging from 10 to 60 minutes before being cooled and filtered to record absorbance. Minerals were identified using IR, XRD, and elemental chemical composition of fusion mixture following Hutchinson’s method. The clay was montmorillonite in character with subordinate Kaolinite and Illite and unaltered tuff in form plagioclase and feldspars. Samples were subjected to hydrochloric and sulfuric acid activation with 10, 20 and 30% acid at 105°C. Bleaching efficiency for cotton and sunflower oils were. Study revealed that maximum decrease in absorbance of bleached oil was attained with clay leached in 30% sulfuric acid when the oil was in contact with clay for 30 to 40 minute at 90°C. Results obtained in which the performance of locally prepared clays was expressed in terms of percentage decrease in absorbance of oil showed that, the acid-activated samples were more effective in the bleaching of oils than raw clay. The percentage decrease in absorbance of sunflower oil of 80% was achieved with clay leached in 20% hydrochloric acid. Yet cotton oil attained highest percentage absorbance of 55% during the bleaching step. This study revealed for the first time the use Kangole clay in bleaching oils. It’s the first time the clay minerals in admixture mined at Kangole has been shown to contain montmorillonite, illite, kaolinite, feldspars and plagioclase which contribute to its bleaching activity.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"196 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79909483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-04-30DOI: 10.4172/2155-9872.1000319
Y. Kudo, A. Kaminagayoshi, S. Ikeda, H. Yamada, S. Katsuta
Extraction constants (Kex±) for the extraction of sodium salts (NaA) with 18-crown-6 ether (18C6) from water (w) into nitrobenzene (NB) were determined at 298 K, together with the determination of individual distribution constants (KD,A) of several pairing anions A−. The symbols Kex± and KD,A were defined as [NaL+]NB[A−]NB/([Na+][L]NB[A−]) at L = 18C6 and [A−]NB/[A−], respectively; the subscript “NB” shows the NB phase. Also, ion-pair formation constants for sodium 2,4-dinitrophenolate (NaDnp) and its ion pair complex with 18C6 in water were determined by potentiometry with a Na+-selective electrode. Standardized (S) KD,A values were briefly calculated from the following thermodynamic cycle: KD,A S = Kex±/KD,Na SKNaL,NB. Here, KD,Na S and KNaL,NB denote the standardized individual distribution-constant of Na+ into and a complex formation constant for NaL+ in the NB phase, respectively. Moreover, equilibrium potential differences (Δφeq) at the NB/w interface were estimated from the relation Δφeq = 0.05916log (KD,A S/KD,A) at 298 K. The Δφeq values of A− = F3CCO2 −, MnO4 −, ReO4 − and Dnp− were determined for comparison with the value of picrate ion. The plot of log Kex± versus Δφeq gave a positive correlation at (correlation coefficient)2 = 0.748.
{"title":"Brief Determination of Standard Formal Potentials for the Transfers of Several Pairing Anions across the Nitrobenzene/Water Interface by Na(I) Extraction with 18-Crown-6 Ether","authors":"Y. Kudo, A. Kaminagayoshi, S. Ikeda, H. Yamada, S. Katsuta","doi":"10.4172/2155-9872.1000319","DOIUrl":"https://doi.org/10.4172/2155-9872.1000319","url":null,"abstract":"Extraction constants (Kex±) for the extraction of sodium salts (NaA) with 18-crown-6 ether (18C6) from water (w) into nitrobenzene (NB) were determined at 298 K, together with the determination of individual distribution constants (KD,A) of several pairing anions A−. The symbols Kex± and KD,A were defined as [NaL+]NB[A−]NB/([Na+][L]NB[A−]) at L = 18C6 and [A−]NB/[A−], respectively; the subscript “NB” shows the NB phase. Also, ion-pair formation constants for sodium 2,4-dinitrophenolate (NaDnp) and its ion pair complex with 18C6 in water were determined by potentiometry with a Na+-selective electrode. Standardized (S) KD,A values were briefly calculated from the following thermodynamic cycle: KD,A S = Kex±/KD,Na SKNaL,NB. Here, KD,Na S and KNaL,NB denote the standardized individual distribution-constant of Na+ into and a complex formation constant for NaL+ in the NB phase, respectively. Moreover, equilibrium potential differences (Δφeq) at the NB/w interface were estimated from the relation Δφeq = 0.05916log (KD,A S/KD,A) at 298 K. The Δφeq values of A− = F3CCO2 −, MnO4 −, ReO4 − and Dnp− were determined for comparison with the value of picrate ion. The plot of log Kex± versus Δφeq gave a positive correlation at (correlation coefficient)2 = 0.748.","PeriodicalId":14865,"journal":{"name":"Journal of analytical and bioanalytical techniques","volume":"377 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80606455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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