We describe the specific spectral signature of different phospholipids and sphingolipids in the far infrared. Three specific spectral domains have been found: the head group contributions (600 and 480 cm−1); the modes of the torsion motion of the hydrocarbon chains and of the skeleton vibration (460 to 180 cm−1); and the hydrogen-bonding continuum (below 300 cm−1). Marker bands for individual phospholipids are distinguished.
{"title":"Specific Far Infrared Spectroscopic Properties of Phospholipids","authors":"R. Hielscher, P. Hellwig","doi":"10.1155/2012/279650","DOIUrl":"https://doi.org/10.1155/2012/279650","url":null,"abstract":"We describe the specific spectral signature of different phospholipids and sphingolipids in the far infrared. Three specific spectral domains have been found: the head group contributions (600 and 480 cm−1); the modes of the torsion motion of the hydrocarbon chains and of the skeleton vibration (460 to 180 cm−1); and the hydrogen-bonding continuum (below 300 cm−1). Marker bands for individual phospholipids are distinguished.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"5 1","pages":"525-532"},"PeriodicalIF":0.0,"publicationDate":"2012-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84455354","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}
Z. Hongyan, P. Xiao, Wu Ling-yan, Liu Bo, Qi Ze-Ming, Wang Yu-yin
In the present study, synchrotron-based Fourier transform-infrared (FTIR) microspectroscopy is used to analyze the biochemical composition of the striatal neurons in normal and Parkinson's disease (PD) rat brain tissues. The rat model of Parkinson's disease is established by destroying the nigrostriatal pathway with 6-hydroxydopamine (6-OHDA). The detailed spectral analyses show the significant changes of cellular compositions such as lipids, and proteins in the striatal neurons of 6-OHDA-lesioned PD rats with respect to control neurons. As a result, the intensities of spectral absorption assigned to lipid of the striatal neurons in PD rats are higher than in control animals. Furthermore, the unsaturation levels of phospholipids decrease in PD neurons with respect to control neurons, indicating a high level of lipid peroxidation. The analysis of protein secondary structure shows the significantly higher ratio of 𝛽-sheet in PD neurons compared to that of control neurons, suggesting that the abnormal protein structure occurs before their morphological appearances in the striatal neurons. These findings suggest that the biochemical changes in neurons could be involved in the pathogenesis of Parkinson's disease.
{"title":"Synchrotron FTIR Microspectroscopy Study of the Striatum in 6-Hydroxydopamine Rat Model of Parkinson's Disease","authors":"Z. Hongyan, P. Xiao, Wu Ling-yan, Liu Bo, Qi Ze-Ming, Wang Yu-yin","doi":"10.1155/2012/176937","DOIUrl":"https://doi.org/10.1155/2012/176937","url":null,"abstract":"In the present study, synchrotron-based Fourier transform-infrared (FTIR) microspectroscopy is used to analyze the biochemical composition of the striatal neurons in normal and Parkinson's disease (PD) rat brain tissues. The rat model of Parkinson's disease is established by destroying the nigrostriatal pathway with 6-hydroxydopamine (6-OHDA). The detailed spectral analyses show the significant changes of cellular compositions such as lipids, and proteins in the striatal neurons of 6-OHDA-lesioned PD rats with respect to control neurons. As a result, the intensities of spectral absorption assigned to lipid of the striatal neurons in PD rats are higher than in control animals. Furthermore, the unsaturation levels of phospholipids decrease in PD neurons with respect to control neurons, indicating a high level of lipid peroxidation. The analysis of protein secondary structure shows the significantly higher ratio of 𝛽-sheet in PD neurons compared to that of control neurons, suggesting that the abnormal protein structure occurs before their morphological appearances in the striatal neurons. These findings suggest that the biochemical changes in neurons could be involved in the pathogenesis of Parkinson's disease.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"1 1","pages":"229-238"},"PeriodicalIF":0.0,"publicationDate":"2012-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90653111","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 present investigation deals with the study of in vivo laser-induced chlorophyll florescence spectra (LICF) of safflower leaves (Carthamus tinctorius L.) for X-rays + EMS-treated plants. Seeds were treated with different doses of X- ray + EMS (5, 8, 12, 25, and 30 Kr + 0.5% EMS) and were grown in the green house. The effects of the concerned treatment on chlorophyll (Chl) contents and Chl fluorescence were investigated after 7 days of germination. Results obtained revealed that the values of Chl contents, intensity of Chl fluorescence spectra, and fluorescence intensity ratio (FIR) F685/F730 are directly correlated with the treatment doses monitored. The treatment sets of 8, 12, and 25 Kr + 0.5% EMS doses showed an increase in FIR and thereby a decrease in the Chl contents. However, the lowest treatment dose of 5 Kr + 0.5% showed a decrease in FIR and thereby an increase in chlorophyll contents. Safflower seeds treated with 30 Kr + 0.5% EMS were proved to be lethal as they showed no germination. Thus, our study demonstrates early detection of chlorophyll damage caused by various physical and chemical mutagens through the application of LICF spectra.
{"title":"Chlorophyll Fluorescence Spectra as an Indicator of X-Ray + EMS-Induced Phytotoxicity in Safflower","authors":"J. Pandey, P. Srivastava, R. Yadav, R. Gopal","doi":"10.1155/2012/951064","DOIUrl":"https://doi.org/10.1155/2012/951064","url":null,"abstract":"The present investigation deals with the study of in vivo laser-induced chlorophyll florescence spectra (LICF) of safflower leaves (Carthamus tinctorius L.) for X-rays + EMS-treated plants. Seeds were treated with different doses of X- ray + EMS (5, 8, 12, 25, and 30 Kr + 0.5% EMS) and were grown in the green house. The effects of the concerned treatment on chlorophyll (Chl) contents and Chl fluorescence were investigated after 7 days of germination. Results obtained revealed that the values of Chl contents, intensity of Chl fluorescence spectra, and fluorescence intensity ratio (FIR) F685/F730 are directly correlated with the treatment doses monitored. The treatment sets of 8, 12, and 25 Kr + 0.5% EMS doses showed an increase in FIR and thereby a decrease in the Chl contents. However, the lowest treatment dose of 5 Kr + 0.5% showed a decrease in FIR and thereby an increase in chlorophyll contents. Safflower seeds treated with 30 Kr + 0.5% EMS were proved to be lethal as they showed no germination. Thus, our study demonstrates early detection of chlorophyll damage caused by various physical and chemical mutagens through the application of LICF spectra.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"58 1","pages":"207-214"},"PeriodicalIF":0.0,"publicationDate":"2012-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87743413","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}
V. Bório, Rubens Vinha, R. Nicolau, H. P. M. D. Oliveira, C. J. Lima, L. Silveira
This work used dispersive Raman spectroscopy to evaluate acetaminophen in commercially available formulations as an analytical methodology for quality control in the pharmaceutical industry. Raman spectra were collected using a near-infrared dispersive Raman spectrometer (830 nm, 50 mW, 20 s exposure time) coupled to a fiber optic probe. Solutions of acetaminophen diluted in excipient (70 to 120% of the commercial concentration of 200 mg/mL) were used to develop a calibration model based on partial least squares (PLSs) applied to Raman spectra of solutions and, subsequently, obtain linearity, accuracy, precision (repeatability), and sensitivity of the method using the near-infrared spectroscopy (NIRS) as a gold standard method. This model was used to predict the acetaminophen concentration in commercial samples from different lots of acetaminophen formulations (200 mg/mL) with a PLS-prediction error of about 0.6%. Commercial medicines had PLS predicted concentrations errors below 2.5%, whereas NIRS had an error of about 3.7% compared to the label concentration. It has been demonstrated the applicability of Raman spectroscopy with fiber probe for quality control in pharmaceutical industry of commercial formulations.
{"title":"Quantitative Evaluation of Acetaminophen in Oral Solutions by Dispersive Raman Spectroscopy for Quality Control","authors":"V. Bório, Rubens Vinha, R. Nicolau, H. P. M. D. Oliveira, C. J. Lima, L. Silveira","doi":"10.1155/2012/108041","DOIUrl":"https://doi.org/10.1155/2012/108041","url":null,"abstract":"This work used dispersive Raman spectroscopy to evaluate acetaminophen in commercially available formulations as an analytical methodology for quality control in the pharmaceutical industry. Raman spectra were collected using a near-infrared dispersive Raman spectrometer (830 nm, 50 mW, 20 s exposure time) coupled to a fiber optic probe. Solutions of acetaminophen diluted in excipient (70 to 120% of the commercial concentration of 200 mg/mL) were used to develop a calibration model based on partial least squares (PLSs) applied to Raman spectra of solutions and, subsequently, obtain linearity, accuracy, precision (repeatability), and sensitivity of the method using the near-infrared spectroscopy (NIRS) as a gold standard method. This model was used to predict the acetaminophen concentration in commercial samples from different lots of acetaminophen formulations (200 mg/mL) with a PLS-prediction error of about 0.6%. Commercial medicines had PLS predicted concentrations errors below 2.5%, whereas NIRS had an error of about 3.7% compared to the label concentration. It has been demonstrated the applicability of Raman spectroscopy with fiber probe for quality control in pharmaceutical industry of commercial formulations.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"1 1","pages":"215-228"},"PeriodicalIF":0.0,"publicationDate":"2012-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79218496","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}
Recent researches have mainly displayed the significant role of stem cells in tissue renewal and homeostasis with their unique capacity to develop different cell types. These findings have clarified the importance of stem cells to improve the effectiveness of any cell therapy for regenerative medicine. Identification of purity and differentiation stages of stem cells are the greatest challenges of stem cell biology and regenerative medicine. The existing methods to carefully monitor and characterize the stem cells have some unwanted effects on the properties of stem cells, and these methods also do not provide real-time information about cellular conditions. These challenges enforce the usage of nondestructive, rapid, sensitive, high quality, label-free, cheep, and innovative chemical monitoring methods. In this context, vibrational spectroscopy provides promissing alternative to get new information into the field of stem cell biology for chemical analysis, quantification, and imaging of stem cells. Raman and infrared spectroscopy and imaging can be used as a new complimentary spectroscopic approaches to gain new insight into stem cell reseaches for future therapeutic and regenerative medicines. In this paper, recent developments in applications of vibrational spectroscopy techniques for stem cell characterization and identification are presented.
{"title":"Role of Vibrational Spectroscopy in Stem Cell Research","authors":"C. Aksoy, F. Severcan","doi":"10.1155/2012/513286","DOIUrl":"https://doi.org/10.1155/2012/513286","url":null,"abstract":"Recent researches have mainly displayed the significant role of stem cells in tissue renewal and homeostasis with their unique capacity to develop different cell types. These findings have clarified the importance of stem cells to improve the effectiveness of any cell therapy for regenerative medicine. Identification of purity and differentiation stages of stem cells are the greatest challenges of stem cell biology and regenerative medicine. The existing methods to carefully monitor and characterize the stem cells have some unwanted effects on the properties of stem cells, and these methods also do not provide real-time information about cellular conditions. These challenges enforce the usage of nondestructive, rapid, sensitive, high quality, label-free, cheep, and innovative chemical monitoring methods. In this context, vibrational spectroscopy provides promissing alternative to get new information into the field of stem cell biology for chemical analysis, quantification, and imaging of stem cells. Raman and infrared spectroscopy and imaging can be used as a new complimentary spectroscopic approaches to gain new insight into stem cell reseaches for future therapeutic and regenerative medicines. In this paper, recent developments in applications of vibrational spectroscopy techniques for stem cell characterization and identification are presented.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"25 1","pages":"167-184"},"PeriodicalIF":0.0,"publicationDate":"2012-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81667242","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}
Lei Huang, Lianzhi Li, Haili Li, Chaohui Gao, Hui Cui, Xiangshi Tan
The interaction between chloramphenicol (CHL) and neuroglobin (Ngb) has been investigated by using fluorescence, synchronous fluorescence, UV-Vis and circular dichroism (CD) spectroscopy. It has been found that CHL molecule can quench the intrinsic fluorescence of Ngb in a way of dynamic quenching mechanism, which was supported by UV-Vis spectral data. Their effective quenching constants (𝐾SV) are 2.2×104, 2.6×104, and3.1×104 L·mol−1 at 298 K, 303 K, and 308 K, respectively. The enthalpy change (Δ𝐻) and entropy change (Δ𝑆) for this reaction are 26.42 kJ·mol−1 and 171.7 J·K−1, respectively. It means that the hydrophobic interaction is the main intermolecular force of the interaction between CHL and Ngb. Synchronous fluorescence spectra showed that the microenvironment of tryptophan and tyrosine residues of Ngb has been changed slightly. The fluorescence quenching efficiency of CHL to tyrosine residues is a little bit more than that to tryptophan residues of Ngb. Furthermore, CD spectra indicated that CHL can induce the formation of α-helix of Ngb.
{"title":"Multispectroscopic Study of the Interaction of Chloramphenicol with Human Neuroglobin","authors":"Lei Huang, Lianzhi Li, Haili Li, Chaohui Gao, Hui Cui, Xiangshi Tan","doi":"10.1155/2012/192591","DOIUrl":"https://doi.org/10.1155/2012/192591","url":null,"abstract":"The interaction between chloramphenicol (CHL) and neuroglobin (Ngb) has been investigated by using fluorescence, synchronous fluorescence, UV-Vis and circular dichroism (CD) spectroscopy. It has been found that CHL molecule can quench the intrinsic fluorescence of Ngb in a way of dynamic quenching mechanism, which was supported by UV-Vis spectral data. Their effective quenching constants (𝐾SV) are 2.2×104, 2.6×104, and3.1×104 L·mol−1 at 298 K, 303 K, and 308 K, respectively. The enthalpy change (Δ𝐻) and entropy change (Δ𝑆) for this reaction are 26.42 kJ·mol−1 and 171.7 J·K−1, respectively. It means that the hydrophobic interaction is the main intermolecular force of the interaction between CHL and Ngb. Synchronous fluorescence spectra showed that the microenvironment of tryptophan and tyrosine residues of Ngb has been changed slightly. The fluorescence quenching efficiency of CHL to tyrosine residues is a little bit more than that to tryptophan residues of Ngb. Furthermore, CD spectra indicated that CHL can induce the formation of α-helix of Ngb.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"13 1","pages":"143-154"},"PeriodicalIF":0.0,"publicationDate":"2012-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86964505","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 goal of this work was to evaluate the ability of Raman spectroscopy to identify molecular organization and chemical composition of extracellular matrix such as the collagen fibers arrangement, the level of mineralization, and the carbonate accumulation in mineral phase in spongy bone of the human head of the femur. Changes in composition and structure of the spongy bone tissue were illustrated using maps of polarized Raman spectra. In particular, the purpose of the present study was determination of arrangement of mineralized collagen on surface of trabecula by using transformations of Raman spectra maps. Transformations of Raman spectra maps were needed in order to remove impact of chemical composition on images of Raman spectra map, which display the collagen fibers orientation. These transformations allow to obtain simultaneously the distribution of constituents of bone and arrangement of collagen fibers on tissue surface. A method to indicate the collagen orientations is developed to understand the molecular organization in healthy and unhealthy bone at the microstructural level.
{"title":"Determination of Collagen Fibers Arrangement in Bone Tissue by Using Transformations of Raman Spectra Maps","authors":"T. Buchwald, M. Kozielski, M. Szybowicz","doi":"10.1155/2012/261487","DOIUrl":"https://doi.org/10.1155/2012/261487","url":null,"abstract":"The goal of this work was to evaluate the ability of Raman spectroscopy to identify molecular organization and chemical composition of extracellular matrix such as the collagen fibers arrangement, the level of mineralization, and the carbonate accumulation in mineral phase in spongy bone of the human head of the femur. Changes in composition and structure of the spongy bone tissue were illustrated using maps of polarized Raman spectra. In particular, the purpose of the present study was determination of arrangement of mineralized collagen on surface of trabecula by using transformations of Raman spectra maps. Transformations of Raman spectra maps were needed in order to remove impact of chemical composition on images of Raman spectra map, which display the collagen fibers orientation. These transformations allow to obtain simultaneously the distribution of constituents of bone and arrangement of collagen fibers on tissue surface. A method to indicate the collagen orientations is developed to understand the molecular organization in healthy and unhealthy bone at the microstructural level.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"75 1","pages":"107-117"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76404601","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}
C. Nowak, D. Schach, Marc Großerüschkamp, W. Knoll, R. Naumann
A two-layer gold surface is developed for use with electrochemistry followed by surface-enhanced infrared ab- sorption spectroscopy (SEIRAS) consisting of a conducting underlayer onto which Au nanoparticles (AuNPs) are grown by self-catalyzed electroless deposition. AuNPs are grown on protruding substructures of the 25 nm thin underlayer. The enhance- ment factor of the two-layer gold surface is controlled by the growth conditions. Cytochrome c adsorbed to a self-assembled monolayer of mercaptoethanol is used as a benchmark system for the investigation of complex heme proteins from the respira- tory chain such as cytochrome c oxidase and the bc1 complex. Under optimum conditions the absorbance of the amide I band of cytochrome c is increased by a factor of 5 vs. classical SEIRAS surface. Reversible reduction/oxidation of cytochrome c on the two-layer gold surface is shown to take place by cyclic voltammetry.
{"title":"Cytochrome C as a benchmark system for a two-layer gold surface with improved surface-enhancement for spectro-electrochemistry","authors":"C. Nowak, D. Schach, Marc Großerüschkamp, W. Knoll, R. Naumann","doi":"10.3233/SPE-2010-0425","DOIUrl":"https://doi.org/10.3233/SPE-2010-0425","url":null,"abstract":"A two-layer gold surface is developed for use with electrochemistry followed by surface-enhanced infrared ab- sorption spectroscopy (SEIRAS) consisting of a conducting underlayer onto which Au nanoparticles (AuNPs) are grown by self-catalyzed electroless deposition. AuNPs are grown on protruding substructures of the 25 nm thin underlayer. The enhance- ment factor of the two-layer gold surface is controlled by the growth conditions. Cytochrome c adsorbed to a self-assembled monolayer of mercaptoethanol is used as a benchmark system for the investigation of complex heme proteins from the respira- tory chain such as cytochrome c oxidase and the bc1 complex. Under optimum conditions the absorbance of the amide I band of cytochrome c is increased by a factor of 5 vs. classical SEIRAS surface. Reversible reduction/oxidation of cytochrome c on the two-layer gold surface is shown to take place by cyclic voltammetry.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"122 1","pages":"173-176"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73356030","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}
Marc Grosserueschkamp, C. Nowak, W. Knoll, R. Naumann
Heme proteins such as cytochrome c (cc) play a fundamental role in many biological processes. Surface-enhanced resonance Raman spectroscopy (SERRS) combined with electrochemical methods is an ideal tool to study the redox processes of heme proteins. In this context we designed a new measuring cell allowing for simultaneous electrochemical manipulation and high sensitive SERRS measurements of heme proteins. The measuring cell is based on an inverted rotating disc electrode for excitation by using a confocal Raman microscope. Furthermore, we developed a SER(R)S-active silver modified silver substrate for spectro-electrochemical applications. For this purpose silver nanoparticles (AgNPs) were adsorbed on top of a planar silver surface. The substrate was optimized for an excitation wavelength of 413 nm corresponding to the resonance frequency of heme structures. An enhancement factor of 10 5 was achieved. The high performance of the new measuring cell in combination with
{"title":"Time-resolved surface-enhanced resonance Raman spectro-electrochemistry of heme proteins","authors":"Marc Grosserueschkamp, C. Nowak, W. Knoll, R. Naumann","doi":"10.3233/SPE-2010-0414","DOIUrl":"https://doi.org/10.3233/SPE-2010-0414","url":null,"abstract":"Heme proteins such as cytochrome c (cc) play a fundamental role in many biological processes. Surface-enhanced resonance Raman spectroscopy (SERRS) combined with electrochemical methods is an ideal tool to study the redox processes of heme proteins. In this context we designed a new measuring cell allowing for simultaneous electrochemical manipulation and high sensitive SERRS measurements of heme proteins. The measuring cell is based on an inverted rotating disc electrode for excitation by using a confocal Raman microscope. Furthermore, we developed a SER(R)S-active silver modified silver substrate for spectro-electrochemical applications. For this purpose silver nanoparticles (AgNPs) were adsorbed on top of a planar silver surface. The substrate was optimized for an excitation wavelength of 413 nm corresponding to the resonance frequency of heme structures. An enhancement factor of 10 5 was achieved. The high performance of the new measuring cell in combination with","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"82 1","pages":"125-129"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74180489","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}
Phosphorus‒31 saturation‒transfer NMR spectroscopy provides an elegant means to study fluxes through the creatine kinase reaction in human skeletal muscle. To obtain reliable quantitative kinetic information, experimental imperfections, such as incomplete saturation and radiofrequency bleed over need to be addressed appropriately. In resting muscle, creatine kinase was near equilibrium both in normal controls and in a patient with impaired oxidative phosphorylation. Oral intake of high doses of creatine monohydrate for several days resulted in significantly increased concentrations of phosphocreatine but had no measurable effect on the phosphocreatine resynthesis rate in resting muscle.
{"title":"Magnetization‒transfer 31P NMR of biochemical exchange in vivo: Application to creatine kinase kinetics","authors":"H. Möller, D. Wiedermann","doi":"10.1155/2002/326454","DOIUrl":"https://doi.org/10.1155/2002/326454","url":null,"abstract":"Phosphorus‒31 saturation‒transfer NMR spectroscopy provides an elegant means to study fluxes through the creatine kinase reaction in human skeletal muscle. To obtain reliable quantitative kinetic information, experimental imperfections, such as incomplete saturation and radiofrequency bleed over need to be addressed appropriately. In resting muscle, creatine kinase was near equilibrium both in normal controls and in a patient with impaired oxidative phosphorylation. Oral intake of high doses of creatine monohydrate for several days resulted in significantly increased concentrations of phosphocreatine but had no measurable effect on the phosphocreatine resynthesis rate in resting muscle.","PeriodicalId":51163,"journal":{"name":"Spectroscopy-An International Journal","volume":"4 1","pages":"207-216"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73133695","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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