K. Savithri, B. C. V. Kumar, H. K. Vivek, H. D. Revanasiddappa
A bidentate (N- and O-) imine-based ligand (L1) and its metal complexes of types [ (L1)2] (C1), [ (L1)(Phen)] (C2), [ (L1)2] (C3), and [ (L1)(Phen)] (C4) (L1 = 2-((E)-(6-fluorobenzo[d]thiazol-2-ylimino)methyl)-4-chlorophenol and phen = 1,10-phenanthroline) were synthesized as potential chemotherapeutic drug candidates. The prepared complexes were structurally characterized by spectral techniques (NMR, FT-IR, LC-MS, EPR, and electronic absorption), thermogravimetric analysis (TGA/DTA), magnetic moment, and CHNO elemental analysis. Spectroscopic studies suggested the distorted octahedral structure for all complexes. In vitro bioassay studies include binding and nuclease activities of the ligand and its complexes with target calf thymus- (CT-) DNA were carried out by employing UV-Vis, fluorescence spectroscopy, viscosity, and gel electrophoresis techniques. The extent of binding propensity was determined quantitatively by and values which revealed a higher binding affinity for C2 and C4 as compared to C1 and C3. In addition, the scavenging superoxide anion free radical ( ) activity of metal complexes was determined by nitroblue tetrazolium (NBT) light reduction assay. Molecular docking studies with DNA and SOD enzyme were also carried out on these compounds. The antimicrobial study has shown that all the compounds are potential antibacterial agents against Gram-negative bacterial strains and better antifungal agents with respect to standard drugs used.
{"title":"Synthesis and Characterization of Cobalt(III) and Copper(II) Complexes of 2-((E)-(6-Fluorobenzo[d]thiazol-2-ylimino) methyl)-4-chlorophenol: DNA Binding and Nuclease Studies—SOD and Antimicrobial Activities","authors":"K. Savithri, B. C. V. Kumar, H. K. Vivek, H. D. Revanasiddappa","doi":"10.1155/2018/8759372","DOIUrl":"https://doi.org/10.1155/2018/8759372","url":null,"abstract":"A bidentate (N- and O-) imine-based ligand (L1) and its metal complexes of types [ (L1)2] (C1), [ (L1)(Phen)] (C2), [ (L1)2] (C3), and [ (L1)(Phen)] (C4) (L1 = 2-((E)-(6-fluorobenzo[d]thiazol-2-ylimino)methyl)-4-chlorophenol and phen = 1,10-phenanthroline) were synthesized as potential chemotherapeutic drug candidates. The prepared complexes were structurally characterized by spectral techniques (NMR, FT-IR, LC-MS, EPR, and electronic absorption), thermogravimetric analysis (TGA/DTA), magnetic moment, and CHNO elemental analysis. Spectroscopic studies suggested the distorted octahedral structure for all complexes. In vitro bioassay studies include binding and nuclease activities of the ligand and its complexes with target calf thymus- (CT-) DNA were carried out by employing UV-Vis, fluorescence spectroscopy, viscosity, and gel electrophoresis techniques. The extent of binding propensity was determined quantitatively by and values which revealed a higher binding affinity for C2 and C4 as compared to C1 and C3. In addition, the scavenging superoxide anion free radical ( ) activity of metal complexes was determined by nitroblue tetrazolium (NBT) light reduction assay. Molecular docking studies with DNA and SOD enzyme were also carried out on these compounds. The antimicrobial study has shown that all the compounds are potential antibacterial agents against Gram-negative bacterial strains and better antifungal agents with respect to standard drugs used.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"51 1","pages":"1-15"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90282041","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}
Effect of zinc oxide nanoparticles on anticorrosion performance has been studied in conductive polyaniline containing zinc-rich primer in 3.5 wt% NaCl solution, using Electrochemical Impedance Spectroscopy (EIS) and localized electrochemical Scanning Vibrating Electrode Technique (SVET). The results showed that the addition of nano-zinc oxide particles in conductive polyaniline containing zinc-rich primer made the reaction of zinc more stable and slower, further increasing the effective cathodic protection period. EIS and SVET results confirmed that three performance evolution stages were obtained for zinc-rich primer being immersed in 3.5 wt% sodium chloride solution.
{"title":"Application of Electrochemical Techniques on Study of Effect of Nano-ZnO in Conductive Polyaniline Containing Zinc-Rich Primer","authors":"Ximing Li, H. Castaneda","doi":"10.1155/2018/7160381","DOIUrl":"https://doi.org/10.1155/2018/7160381","url":null,"abstract":"Effect of zinc oxide nanoparticles on anticorrosion performance has been studied in conductive polyaniline containing zinc-rich primer in 3.5 wt% NaCl solution, using Electrochemical Impedance Spectroscopy (EIS) and localized electrochemical Scanning Vibrating Electrode Technique (SVET). The results showed that the addition of nano-zinc oxide particles in conductive polyaniline containing zinc-rich primer made the reaction of zinc more stable and slower, further increasing the effective cathodic protection period. EIS and SVET results confirmed that three performance evolution stages were obtained for zinc-rich primer being immersed in 3.5 wt% sodium chloride solution.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"19 1","pages":"1-15"},"PeriodicalIF":0.0,"publicationDate":"2018-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82543072","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}
Kumbam Lingeshwar Reddy, Anabathula Manoj Kumar, Abhimanew Dhir, V. Krishnan
Selective and sensitive detection of explosive materials through a simple approach is an attractive area of research having implications on public safety and homeland security. Considering this implication in mind, a new Ni-anthracene complex was designed and synthesized and has been demonstrated as an efficient fluorescence chemosensor for the selective and sensitive detection of 2,4,6-trinitrophenol. Firstly, a fluorescent anthracene ligand (A) was synthesized by treating anthracene-9-carboxaldehyde with 1,3-diaminopropane in presence of a weak acid. To achieve superior selectivity and great quenching efficiency for 2,4,6-trinitrophenol (TNP), a Ni complex, namely, [Ni( -L)(NO3)] (B), was synthesized via the reaction of A with Ni(NO3)2·6H2O. Complex B showed strong emission peak ( ) at 412 nm and exhibited high selectivity towards TNP among other nitroaromatics and anions. 100 equivalents of TNP made 95% fluorescence quenching of B and its detection limit for TNP was calculated as 2.8 μM.
{"title":"New Ni-Anthracene Complex for Selective and Sensitive Detection of 2,4,6-Trinitrophenol","authors":"Kumbam Lingeshwar Reddy, Anabathula Manoj Kumar, Abhimanew Dhir, V. Krishnan","doi":"10.1155/2018/1321427","DOIUrl":"https://doi.org/10.1155/2018/1321427","url":null,"abstract":"Selective and sensitive detection of explosive materials through a simple approach is an attractive area of research having implications on public safety and homeland security. Considering this implication in mind, a new Ni-anthracene complex was designed and synthesized and has been demonstrated as an efficient fluorescence chemosensor for the selective and sensitive detection of 2,4,6-trinitrophenol. Firstly, a fluorescent anthracene ligand (A) was synthesized by treating anthracene-9-carboxaldehyde with 1,3-diaminopropane in presence of a weak acid. To achieve superior selectivity and great quenching efficiency for 2,4,6-trinitrophenol (TNP), a Ni complex, namely, [Ni( -L)(NO3)] (B), was synthesized via the reaction of A with Ni(NO3)2·6H2O. Complex B showed strong emission peak ( ) at 412 nm and exhibited high selectivity towards TNP among other nitroaromatics and anions. 100 equivalents of TNP made 95% fluorescence quenching of B and its detection limit for TNP was calculated as 2.8 μM.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"15 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78314095","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}
Autofluorescence of secondary compounds contained in plant secretory cells may be applied to the analysis of medicinal plants for pharmacy. Emission and prevailing fluorescent pharmaceuticals have been estimated in several models of species such as Salvia officinalis, Berberis vulgaris, Humulus lupulus, and Matricaria chamomilla, by luminescence microscopy, microspectrofluorimetry, and confocal microscopy.
{"title":"Application of Autofluorescence for Analysis of Medicinal Plants","authors":"V. V. Roshchina, A. Kuchin, V. Yashin","doi":"10.1155/2017/7159609","DOIUrl":"https://doi.org/10.1155/2017/7159609","url":null,"abstract":"Autofluorescence of secondary compounds contained in plant secretory cells may be applied to the analysis of medicinal plants for pharmacy. Emission and prevailing fluorescent pharmaceuticals have been estimated in several models of species such as Salvia officinalis, Berberis vulgaris, Humulus lupulus, and Matricaria chamomilla, by luminescence microscopy, microspectrofluorimetry, and confocal microscopy.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"24 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78575596","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}
The concepts of standard analysis techniques applied in the field of Fourier spectroscopy treat fundamental aspects insufficiently. For example, the spectra to be inferred are influenced by the noise contribution to the interferometric data, by nonprobed spatial domains which are linked to Fourier coefficients above a certain order, by the spectral limits which are in general not given by the Nyquist assumptions, and by additional parameters of the problem at hand like the zero-path difference. To consider these fundamentals, a probabilistic approach based on Bayes’ theorem is introduced which exploits multivariate normal distributions. For the example application, we model the spectra by the Gaussian process of a Brownian bridge stated by a prior covariance. The spectra themselves are represented by a number of parameters which map linearly to the data domain. The posterior for these linear parameters is analytically obtained, and the marginalisation over these parameters is trivial. This allows the straightforward investigation of the posterior for the involved nonlinear parameters, like the zero-path difference location and the spectral limits, and hyperparameters, like the scaling of the Gaussian process. With respect to the linear problem, this can be interpreted as an implementation of Ockham’s razor principle.
{"title":"Fourier Spectroscopy: A Bayesian Way","authors":"S. Schmuck, J. Svensson","doi":"10.1155/2017/9265084","DOIUrl":"https://doi.org/10.1155/2017/9265084","url":null,"abstract":"The concepts of standard analysis techniques applied in the field of Fourier spectroscopy treat fundamental aspects insufficiently. For example, the spectra to be inferred are influenced by the noise contribution to the interferometric data, by nonprobed spatial domains which are linked to Fourier coefficients above a certain order, by the spectral limits which are in general not given by the Nyquist assumptions, and by additional parameters of the problem at hand like the zero-path difference. To consider these fundamentals, a probabilistic approach based on Bayes’ theorem is introduced which exploits multivariate normal distributions. For the example application, we model the spectra by the Gaussian process of a Brownian bridge stated by a prior covariance. The spectra themselves are represented by a number of parameters which map linearly to the data domain. The posterior for these linear parameters is analytically obtained, and the marginalisation over these parameters is trivial. This allows the straightforward investigation of the posterior for the involved nonlinear parameters, like the zero-path difference location and the spectral limits, and hyperparameters, like the scaling of the Gaussian process. With respect to the linear problem, this can be interpreted as an implementation of Ockham’s razor principle.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"16 1","pages":"1-29"},"PeriodicalIF":0.0,"publicationDate":"2017-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88752959","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}
Johan Borglin, Danni Wang, N. Durr, D. Hanstorp, A. Ben-Yakar, M. Ericson
Despite the inherent spatial confinement of multiphoton processes that arises from focusing through an objective, the maximum imaging depth in conventional multiphoton microscopy is ultimately limited by noise from out-of-focus fluorescence. This is particularly evident when imaging beyond shallow depths in highly scattering tissue as increased laser powers are necessary. The out-of-focus signal originates from multiphoton processes taking place primarily at shallow depths and deteriorates contrast and limits imaging depth. In this paper, annular laser beams are explored as a concept to reduce this background signal in multiphoton microscopy. The approach is theoretically verified by data from simulations and proof of principle is demonstrated on a custom-built experimental multiphoton microscopy platform. Annular laser beams were created by adopting wavefront control using a spatial light modulator and implemented for imaging tissue phantoms simulating turbid media and human skin ex vivo. The signal-to-background ratios were calculated and compared to images acquired with a traditional, filled-aperture Gaussian beam. Experiments in tissue phantom show an improvement in signal-to-background ratio of about 30% when using annular beam illumination in comparison to Gaussian illumination at specific depths. When laser power is not the limiting factor, this approach is expected to provide even greater benefits.
{"title":"Annular Beam Shaping in Multiphoton Microscopy to Reduce Out-of-Focus Background","authors":"Johan Borglin, Danni Wang, N. Durr, D. Hanstorp, A. Ben-Yakar, M. Ericson","doi":"10.1155/2017/7560141","DOIUrl":"https://doi.org/10.1155/2017/7560141","url":null,"abstract":"Despite the inherent spatial confinement of multiphoton processes that arises from focusing through an objective, the maximum imaging depth in conventional multiphoton microscopy is ultimately limited by noise from out-of-focus fluorescence. This is particularly evident when imaging beyond shallow depths in highly scattering tissue as increased laser powers are necessary. The out-of-focus signal originates from multiphoton processes taking place primarily at shallow depths and deteriorates contrast and limits imaging depth. In this paper, annular laser beams are explored as a concept to reduce this background signal in multiphoton microscopy. The approach is theoretically verified by data from simulations and proof of principle is demonstrated on a custom-built experimental multiphoton microscopy platform. Annular laser beams were created by adopting wavefront control using a spatial light modulator and implemented for imaging tissue phantoms simulating turbid media and human skin ex vivo. The signal-to-background ratios were calculated and compared to images acquired with a traditional, filled-aperture Gaussian beam. Experiments in tissue phantom show an improvement in signal-to-background ratio of about 30% when using annular beam illumination in comparison to Gaussian illumination at specific depths. When laser power is not the limiting factor, this approach is expected to provide even greater benefits.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"45 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2017-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90492959","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}
A. M. Hogan, Viswanathan Swaminathan, Nikitha K. Pallegar, S. L. Christian
Glucose is the universal energy source and a critical substrate for lipid synthesis in mammalian cells. Analysis of both glucose and lipid in cells is important for the understanding of the regulation of lipid synthesis in many cell types, but especially adipocytes, the major storage cell for fat in mammals. The fluorescent 7-nitrobenz-2-oxa-1,3-diazole (NBD) derivative of glucose, 2-NBDG, is used to monitor glucose uptake and the lipid-selective fluorophore Nile red is used to monitor lipid accumulation. Previous reports have used NBD-based fluorophores and Nile red simultaneously despite the possibility of spectral overlap. In this study, we determined if these fluorophores were experimentally compatible in preadipocytes and adipocytes stained with 2-NBDG and Nile red separately or costained. We found that Nile red is detectable in the wavelengths necessary to excite and detect 2-NBDG. This interference was further increased by the solvatochromic effect of lipid-localized Nile red. In addition, we found a synergistic increase in fluorescent intensity when both fluorophores were present. Unfortunately, even fine control of the excitation or emission wavelengths did not identify wavelengths suitable for selective detection when cells were costained. Therefore, 2-NBDG and Nile red cannot be used simultaneously—but can likely be used sequentially—to assess glucose uptake and lipid accumulation in lipid-laden cells.
{"title":"Nile Red and 2-NBDG Are Incompatible for the Simultaneous Detection of Lipid and Glucose Accumulation","authors":"A. M. Hogan, Viswanathan Swaminathan, Nikitha K. Pallegar, S. L. Christian","doi":"10.1155/2016/5215086","DOIUrl":"https://doi.org/10.1155/2016/5215086","url":null,"abstract":"Glucose is the universal energy source and a critical substrate for lipid synthesis in mammalian cells. Analysis of both glucose and lipid in cells is important for the understanding of the regulation of lipid synthesis in many cell types, but especially adipocytes, the major storage cell for fat in mammals. The fluorescent 7-nitrobenz-2-oxa-1,3-diazole (NBD) derivative of glucose, 2-NBDG, is used to monitor glucose uptake and the lipid-selective fluorophore Nile red is used to monitor lipid accumulation. Previous reports have used NBD-based fluorophores and Nile red simultaneously despite the possibility of spectral overlap. In this study, we determined if these fluorophores were experimentally compatible in preadipocytes and adipocytes stained with 2-NBDG and Nile red separately or costained. We found that Nile red is detectable in the wavelengths necessary to excite and detect 2-NBDG. This interference was further increased by the solvatochromic effect of lipid-localized Nile red. In addition, we found a synergistic increase in fluorescent intensity when both fluorophores were present. Unfortunately, even fine control of the excitation or emission wavelengths did not identify wavelengths suitable for selective detection when cells were costained. Therefore, 2-NBDG and Nile red cannot be used simultaneously—but can likely be used sequentially—to assess glucose uptake and lipid accumulation in lipid-laden cells.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"140 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2016-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77522578","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}
S. Suresh, Sethu Gunasekaran, Shanmugam Srinivasan
The molecular structure of the three compounds Aceclofenac (I), Salicylic Acid (II), and Piroxicam (III) has been determined using Gaussian 03W program with B3LYP method using 6-311++G (d,p) basis set calculations. The molecular structures were fully optimized with atomic numbering scheme adopted in the study. To understand the mode of binding and molecular interaction, the docking studies of compounds Aceclofenac (I), Salicylic Acid (II), and Piroxicam (III) have been carried out with prostaglandin H2 synthase-1 (1PGE) as target using induced fit docking. The molecular docking results show that the interactions and energy for Aceclofenac, Salicylic Acid, and Piroxicam show the best results when docked with prostaglandin H2 synthase-1 (1PGE). The hydrogen bonding interactions of compound I (Aceclofenac) are prominent with Arginine moiety, those of compound II (Salicylic Acid) are prominent with Tyrosine and Serine moieties, and compound III (Piroxicam) shows such interaction with Tyrosine and Arginine moieties. These interactions of prostaglandin H2 synthase-1 (1PGE) with substrates are responsible for governing COX-1 inhibitor potency which in turn is a direct measure of the potency of the drug.
{"title":"Quantum Chemical Calculations and Molecular Docking Studies of Some NSAID Drugs (Aceclofenac, Salicylic Acid, and Piroxicam) as 1PGE Inhibitors","authors":"S. Suresh, Sethu Gunasekaran, Shanmugam Srinivasan","doi":"10.1155/2016/5281636","DOIUrl":"https://doi.org/10.1155/2016/5281636","url":null,"abstract":"The molecular structure of the three compounds Aceclofenac (I), Salicylic Acid (II), and Piroxicam (III) has been determined using Gaussian 03W program with B3LYP method using 6-311++G (d,p) basis set calculations. The molecular structures were fully optimized with atomic numbering scheme adopted in the study. To understand the mode of binding and molecular interaction, the docking studies of compounds Aceclofenac (I), Salicylic Acid (II), and Piroxicam (III) have been carried out with prostaglandin H2 synthase-1 (1PGE) as target using induced fit docking. The molecular docking results show that the interactions and energy for Aceclofenac, Salicylic Acid, and Piroxicam show the best results when docked with prostaglandin H2 synthase-1 (1PGE). The hydrogen bonding interactions of compound I (Aceclofenac) are prominent with Arginine moiety, those of compound II (Salicylic Acid) are prominent with Tyrosine and Serine moieties, and compound III (Piroxicam) shows such interaction with Tyrosine and Arginine moieties. These interactions of prostaglandin H2 synthase-1 (1PGE) with substrates are responsible for governing COX-1 inhibitor potency which in turn is a direct measure of the potency of the drug.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"86 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2016-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83969715","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}
Alcohol or ethanol is considered the most widely used recreational drug worldwide, and its production, consumption, and sale are strictly regulated by laws. Alcohol content of alcoholic beverages (wine, beers, and spirits) is about 3–50% v/v. Analytical methods to determine the alcohol content must be reliable, precise, and accurate. In this study, the amount of ethanol in several alcoholic beverages was determined using a 45 MHz low-field benchtop NMR (nuclear magnetic resonance) spectrometer. Internal standard and standard addition analytical methods were utilized to quantify ethanol. For both methods, acetic acid or acetonitrile was used as internal standard to quantify alcohol content by using the peak area corresponding to the methyl peaks of ethanol, acetic acid, or acetonitrile. Results showed that internal standard method gave values of percent alcohol that are in close agreement with the indicated label as confirmed by running the samples in a 400 MHz high-field NMR spectrometer using acetic acid as internal standard. This study demonstrates the utility of a benchtop NMR spectrometer that can provide an alternative technique to analyze percent alcohol in alcoholic products.
{"title":"Determination of Alcohol Content in Alcoholic Beverages Using 45 MHz Benchtop NMR Spectrometer","authors":"Meden F. Isaac-Lam","doi":"10.1155/2016/2526946","DOIUrl":"https://doi.org/10.1155/2016/2526946","url":null,"abstract":"Alcohol or ethanol is considered the most widely used recreational drug worldwide, and its production, consumption, and sale are strictly regulated by laws. Alcohol content of alcoholic beverages (wine, beers, and spirits) is about 3–50% v/v. Analytical methods to determine the alcohol content must be reliable, precise, and accurate. In this study, the amount of ethanol in several alcoholic beverages was determined using a 45 MHz low-field benchtop NMR (nuclear magnetic resonance) spectrometer. Internal standard and standard addition analytical methods were utilized to quantify ethanol. For both methods, acetic acid or acetonitrile was used as internal standard to quantify alcohol content by using the peak area corresponding to the methyl peaks of ethanol, acetic acid, or acetonitrile. Results showed that internal standard method gave values of percent alcohol that are in close agreement with the indicated label as confirmed by running the samples in a 400 MHz high-field NMR spectrometer using acetic acid as internal standard. This study demonstrates the utility of a benchtop NMR spectrometer that can provide an alternative technique to analyze percent alcohol in alcoholic products.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"17 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2016-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85321979","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}
Energy levels and oscillator strengths for neutral oxygen have been calculated using the Cowan (CW), SUPERSTRUCTURE (SS), and AUTOSTRUCTURE (AS) atomic structure codes. The results obtained with these atomic codes have been compared with MCHF calculations and experimental values from the National Institute of Standards and Technology (NIST) database.
{"title":"Atomic Structure Calculations for Neutral Oxygen","authors":"N. Alonizan, R. Qindeel, N. B. Nessib","doi":"10.1155/2016/1697561","DOIUrl":"https://doi.org/10.1155/2016/1697561","url":null,"abstract":"Energy levels and oscillator strengths for neutral oxygen have been calculated using the Cowan (CW), SUPERSTRUCTURE (SS), and AUTOSTRUCTURE (AS) atomic structure codes. The results obtained with these atomic codes have been compared with MCHF calculations and experimental values from the National Institute of Standards and Technology (NIST) database.","PeriodicalId":14329,"journal":{"name":"International Journal of Spectroscopy","volume":"89 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2016-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76443436","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}