H. Sato, M. Ishigaki, Akinori Taketani, B. Andriana
As research progresses in the field of life sciences, there is an increased demand for new technologies that can allow us to study intact cells and tissues. The quantitative analysis and mathematical modeling of living things based on empirical data is useful for connecting molecular biology to new areas, such as computational biology. Raman spectroscopy is regarded as one of the possible methods by which we can observe living organisms in a noninvasive manner. This could improve the quality of research in the field of medicine and health and will largely contribute to society in the future. The present review introduces some techniques based on Raman spectroscopy and evaluates their applications in intact live samples.
{"title":"Raman spectroscopy and its use for live cell and tissue analysis","authors":"H. Sato, M. Ishigaki, Akinori Taketani, B. Andriana","doi":"10.3233/BSI-180184","DOIUrl":"https://doi.org/10.3233/BSI-180184","url":null,"abstract":"As research progresses in the field of life sciences, there is an increased demand for new technologies that can allow us to study intact cells and tissues. The quantitative analysis and mathematical modeling of living things based on empirical data is useful for connecting molecular biology to new areas, such as computational biology. Raman spectroscopy is regarded as one of the possible methods by which we can observe living organisms in a noninvasive manner. This could improve the quality of research in the field of medicine and health and will largely contribute to society in the future. The present review introduces some techniques based on Raman spectroscopy and evaluates their applications in intact live samples.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-180184","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43968429","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. Nadeev, Terpilowski, V. Bogdanov, D. A. Khmelevskoy, B. F. Schegolev, S. Surma, V. E. Stefanov, N. V. Goncharov, R. Jenkins
BACKGROUND: Hypomagnetic fields can disrupts the normal functioning of living organisms by a mechanism thought to involve oxidative stress. In erythrocytes, oxidative stress can inter alia lead to changes to hemoglobin content and to hemolysis. OBJECTIVE: To study the effects of hypomagnetism on the state of rat erythrocytes in vitro. METHODS: Rat erythrocytes were exposed to an attenuated magnetic field (AMF) or Earth’s magnetic field (EMF), in the presence of tert-butyl hydroperoxide (TBHP) as inducer of oxidative stress. Determinations: total hemoglobin (and its three forms oxyhemoglobin, methemoglobin, and hemichrome) released from erythrocytes, spectral data (500-700nm); oxygen radical concentrations, electron paramagnetic resonance. RESULTS: AMF and EMF exposed erythrocytes were compared. After 4h incubation at high TBHP concentrations (>700 μM), AMF exposed erythrocytes released significantly more (p<0.05) hemoglobin (Hb), mostly as methemoglobin (metHb). Conversely, after 24 h incubation at low TBHP concentrations (≤ 350 μM), EMF exposed erythrocytes released significantly more (p<0.001) hemoglobin, with metHb as a significant proportion of the total Hb. Erythrocytes exposed to AMF generated more radicals than those exposed to the EMF. CONCLUSION: Under particular conditions of oxidative stress, hypomagnetic fields can disrupt the functional state of erythrocytes and promote cell death; an additive effect is
{"title":"Effects of exposure of rat erythrocytes to a hypogeomagnetic field","authors":"A. Nadeev, Terpilowski, V. Bogdanov, D. A. Khmelevskoy, B. F. Schegolev, S. Surma, V. E. Stefanov, N. V. Goncharov, R. Jenkins","doi":"10.3233/BSI-180181","DOIUrl":"https://doi.org/10.3233/BSI-180181","url":null,"abstract":"BACKGROUND: Hypomagnetic fields can disrupts the normal functioning of living organisms by a mechanism thought to involve oxidative stress. In erythrocytes, oxidative stress can inter alia lead to changes to hemoglobin content and to hemolysis. OBJECTIVE: To study the effects of hypomagnetism on the state of rat erythrocytes in vitro. METHODS: Rat erythrocytes were exposed to an attenuated magnetic field (AMF) or Earth’s magnetic field (EMF), in the presence of tert-butyl hydroperoxide (TBHP) as inducer of oxidative stress. Determinations: total hemoglobin (and its three forms oxyhemoglobin, methemoglobin, and hemichrome) released from erythrocytes, spectral data (500-700nm); oxygen radical concentrations, electron paramagnetic resonance. RESULTS: AMF and EMF exposed erythrocytes were compared. After 4h incubation at high TBHP concentrations (>700 μM), AMF exposed erythrocytes released significantly more (p<0.05) hemoglobin (Hb), mostly as methemoglobin (metHb). Conversely, after 24 h incubation at low TBHP concentrations (≤ 350 μM), EMF exposed erythrocytes released significantly more (p<0.001) hemoglobin, with metHb as a significant proportion of the total Hb. Erythrocytes exposed to AMF generated more radicals than those exposed to the EMF. CONCLUSION: Under particular conditions of oxidative stress, hypomagnetic fields can disrupt the functional state of erythrocytes and promote cell death; an additive effect is","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-180181","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43466112","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 : 2019-01-01Epub Date: 2019-07-09DOI: 10.3233/bsi-190187
Magda El-Shenawee, Nagma Vohra, Tyler Bowman, Keith Bailey
Terahertz imaging and spectroscopy has demonstrated a potential for differentiating tissue types of excised breast cancer tumors. Pulsed terahertz technology provides a broadband frequency range from 0.1 THz to 4 THz for detecting cancerous tissue. Tumor tissue types of interest include cancer typically manifested as infiltrating ductal or lobular carcinomas, fibro-glandular (healthy connective tissues) and fat. In this work, images of breast tumors excised from human and animal models are reviewed. In addition to alternate fresh tissues, breast cancer tissue phantoms are developed to further evaluate terahertz imaging and the potential use of contrast agents. Terahertz results are successfully validated with pathology images, showing strong differentiation between cancerous and healthy tissues for all freshly excised tissues and types. The advantages, challenges and limitations of THz imaging of breast cancer are discussed.
{"title":"Cancer detection in excised breast tumors using terahertz imaging and spectroscopy.","authors":"Magda El-Shenawee, Nagma Vohra, Tyler Bowman, Keith Bailey","doi":"10.3233/bsi-190187","DOIUrl":"10.3233/bsi-190187","url":null,"abstract":"<p><p>Terahertz imaging and spectroscopy has demonstrated a potential for differentiating tissue types of excised breast cancer tumors. Pulsed terahertz technology provides a broadband frequency range from 0.1 THz to 4 THz for detecting cancerous tissue. Tumor tissue types of interest include cancer typically manifested as infiltrating ductal or lobular carcinomas, fibro-glandular (healthy connective tissues) and fat. In this work, images of breast tumors excised from human and animal models are reviewed. In addition to alternate fresh tissues, breast cancer tissue phantoms are developed to further evaluate terahertz imaging and the potential use of contrast agents. Terahertz results are successfully validated with pathology images, showing strong differentiation between cancerous and healthy tissues for all freshly excised tissues and types. The advantages, challenges and limitations of THz imaging of breast cancer are discussed.</p>","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"8 1-2","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/4e/a4/nihms-1570119.PMC7304303.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38073482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There is no doubt that spectroscopy is one of few tools that can bring together researchers from fields as diverse as art, archaeology, astronomy, biology, botany, chemistry, dentistry, computer science, engineering, environmental science, forensics, geology, hydrology, history, mathematics, medicine, nutrition, pharmacy, physics, psychology, sociology, zoology and so on. Apologies for not mentioning each and every discipline! Indeed, it is difficult to imagine a field of research activity where spectroscopy cannot play a role. Spectroscopy has been at the centre of research from searching for water on mars [4] to identifying the life-style of King Richard III of England, whose body was lost for more than 500 years, and eventually found under a car park in Leicester [5]. These are only few examples of how researchers from diverse fields work together to solve problems with spectroscopy often playing a pivotal role. There is little doubt that spectroscopy can be a tool that can unite researchers who otherwise may have few reasons to cross paths, let alone collaborate. The need to encourage and support interdisciplinary research is being made loud and clear by leading authorities in different fields of research. For example, Nobel Laureate Sir Paul Nurse FRS (Fig. 1) produced a report on the UK research councils where he stressed the importance of supporting interdisciplinary research [3]. The fact that he is a strong supporter of interdisciplinary research became clearer when I had the opportunity to engage in discussions with him when he came to present a lecture at my University and also officially open my interdisciplinary research laboratory (see Fig. 1). I write this editorial during a particularly sad period when two of the greatest British scientists have left us, namely Nobel laureate Sir John Sulston FRS and Professor Stephen Hawking FRS. Sir John Sulston FRS will be best remembered for his work on the decoding of the human genome and for his dedication to keeping scientific data freely accessible to the public. He died of stomach cancer on the 6th of March 2018 in Cambridge at the age of 75. Few days later, on the 14th of March, Professor Stephen Hawking FRS who dedicated his life to unlock the secrets of the universe, passed away also in Cambridge at the age of 76. Professor Hawking is a strong supporter of interdisciplinary research. In October 2016, he opened the Leverhulme Centre for the Future of Intelligence [1]. This centre brings together scientists from leading Universities in the UK and USA to engage in cutting edge interdisciplinary research aimed at addressing challenging questions related to artificial intelligence and its impacts. Not only in Europe and USA, but throughout the world, there is a growing acceptance that real progress in finding answers to the challenges that face human beings requires researchers from different disciplines to work together. For example, Tsinghua University in China launched the Tsinghua Labor
{"title":"Spectroscopy: The uniting tool for interdisciplinary research, from art to the history and structure of the universe","authors":"P. Haris","doi":"10.3233/bsi-180180","DOIUrl":"https://doi.org/10.3233/bsi-180180","url":null,"abstract":"There is no doubt that spectroscopy is one of few tools that can bring together researchers from fields as diverse as art, archaeology, astronomy, biology, botany, chemistry, dentistry, computer science, engineering, environmental science, forensics, geology, hydrology, history, mathematics, medicine, nutrition, pharmacy, physics, psychology, sociology, zoology and so on. Apologies for not mentioning each and every discipline! Indeed, it is difficult to imagine a field of research activity where spectroscopy cannot play a role. Spectroscopy has been at the centre of research from searching for water on mars [4] to identifying the life-style of King Richard III of England, whose body was lost for more than 500 years, and eventually found under a car park in Leicester [5]. These are only few examples of how researchers from diverse fields work together to solve problems with spectroscopy often playing a pivotal role. There is little doubt that spectroscopy can be a tool that can unite researchers who otherwise may have few reasons to cross paths, let alone collaborate. The need to encourage and support interdisciplinary research is being made loud and clear by leading authorities in different fields of research. For example, Nobel Laureate Sir Paul Nurse FRS (Fig. 1) produced a report on the UK research councils where he stressed the importance of supporting interdisciplinary research [3]. The fact that he is a strong supporter of interdisciplinary research became clearer when I had the opportunity to engage in discussions with him when he came to present a lecture at my University and also officially open my interdisciplinary research laboratory (see Fig. 1). I write this editorial during a particularly sad period when two of the greatest British scientists have left us, namely Nobel laureate Sir John Sulston FRS and Professor Stephen Hawking FRS. Sir John Sulston FRS will be best remembered for his work on the decoding of the human genome and for his dedication to keeping scientific data freely accessible to the public. He died of stomach cancer on the 6th of March 2018 in Cambridge at the age of 75. Few days later, on the 14th of March, Professor Stephen Hawking FRS who dedicated his life to unlock the secrets of the universe, passed away also in Cambridge at the age of 76. Professor Hawking is a strong supporter of interdisciplinary research. In October 2016, he opened the Leverhulme Centre for the Future of Intelligence [1]. This centre brings together scientists from leading Universities in the UK and USA to engage in cutting edge interdisciplinary research aimed at addressing challenging questions related to artificial intelligence and its impacts. Not only in Europe and USA, but throughout the world, there is a growing acceptance that real progress in finding answers to the challenges that face human beings requires researchers from different disciplines to work together. For example, Tsinghua University in China launched the Tsinghua Labor","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"7 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/bsi-180180","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69857453","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}
Solid supported lipid bilayers (SSLB) play an important role as biomimetic membranes to study protein-membrane interactions. We investigated the orientation of lipids in SSLBs at different temperatures and over time. Especially the stability of the lipid bilayer and structural changes upon lipid phase transition were analyzed by polarized ATR-FTIR spectroscopy and with SSLBs of different lipid compositions. The integrity of a lipid bilayer consisting of POPC or a 1:1 mixture of POPC and POPG is conserved over a wide temperature range and over several hours. Furthermore, we were able to monitor changes in the orientation of the lipid alkyl chains upon lipid phase transition for DMPC and DSPC. This study shows that the combination of solid supported lipid bilayers and polarized ATR-FTIR spectroscopy is very powerful to characterize lipid membranes under different environmental conditions. The sensitivity of this technique will be exploited in future studies to analyze the effect of protein-membrane interaction on lipid orientation.
{"title":"Orientation of lipids in solid supported lipid bilayers studied by polarized ATR-FTIR spectroscopy","authors":"C. Scheibe, K. Hauser","doi":"10.3233/BSI-180173","DOIUrl":"https://doi.org/10.3233/BSI-180173","url":null,"abstract":"Solid supported lipid bilayers (SSLB) play an important role as biomimetic membranes to study protein-membrane interactions. We investigated the orientation of lipids in SSLBs at different temperatures and over time. Especially the stability of the lipid bilayer and structural changes upon lipid phase transition were analyzed by polarized ATR-FTIR spectroscopy and with SSLBs of different lipid compositions. The integrity of a lipid bilayer consisting of POPC or a 1:1 mixture of POPC and POPG is conserved over a wide temperature range and over several hours. Furthermore, we were able to monitor changes in the orientation of the lipid alkyl chains upon lipid phase transition for DMPC and DSPC. This study shows that the combination of solid supported lipid bilayers and polarized ATR-FTIR spectroscopy is very powerful to characterize lipid membranes under different environmental conditions. The sensitivity of this technique will be exploited in future studies to analyze the effect of protein-membrane interaction on lipid orientation.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"7 1","pages":"17-24"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-180173","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46743736","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}
Quoc-Chon Le, T. Lefèvre, R. C.-Gaudreault, G. Laroche, M. Auger
Understanding the efficiency of a transdermal medical drug requires the characterization of its diffusion process, including its diffusion rate, pathways and physical state. The aim of this work is to develop a strategy to achieve this goal. FTIR spectroscopic imaging in conjunction with a Franz cell and HPLC measurements were used to examine the transdermal penetration of deuterated tert-butyl phenylchloroethylurea (tBCEU), a molecule with a potential anticancer action. tBCEU has been solubilized in an expedient solvent mixture and its diffusion in hairless mouse skin has been studied. The results indicate that tBCEU diffuses across the skin for more than 10 hours with a rate comparable to selegiline, an officially-approved transdermal drug. IR image analyses reveal that after 10 hours, tBCEU penetrates skin and that its spatial distribution does not correlate with neither the distribution of lipids nor proteins. tBCEU accumulates in cluster domains but overall low concentrations are found in skin. FTIR spectroscopic imaging additionally reveals that tBCEU is in a crystalline form. The results suggest that tBCEU is conveyed through the skin without preferential pathway. FTIR spectroscopic imaging and transdermal diffusion measurements appear as complementary techniques to investigate drug diffusion in skin.
{"title":"Transdermal diffusion, spatial distribution and physical state of a potential anticancer drug in mouse skin as studied by diffusion and spectroscopic techniques","authors":"Quoc-Chon Le, T. Lefèvre, R. C.-Gaudreault, G. Laroche, M. Auger","doi":"10.3233/BSI-180179","DOIUrl":"https://doi.org/10.3233/BSI-180179","url":null,"abstract":"Understanding the efficiency of a transdermal medical drug requires the characterization of its diffusion process, including its diffusion rate, pathways and physical state. The aim of this work is to develop a strategy to achieve this goal. FTIR spectroscopic imaging in conjunction with a Franz cell and HPLC measurements were used to examine the transdermal penetration of deuterated tert-butyl phenylchloroethylurea (tBCEU), a molecule with a potential anticancer action. tBCEU has been solubilized in an expedient solvent mixture and its diffusion in hairless mouse skin has been studied. The results indicate that tBCEU diffuses across the skin for more than 10 hours with a rate comparable to selegiline, an officially-approved transdermal drug. IR image analyses reveal that after 10 hours, tBCEU penetrates skin and that its spatial distribution does not correlate with neither the distribution of lipids nor proteins. tBCEU accumulates in cluster domains but overall low concentrations are found in skin. FTIR spectroscopic imaging additionally reveals that tBCEU is in a crystalline form. The results suggest that tBCEU is conveyed through the skin without preferential pathway. FTIR spectroscopic imaging and transdermal diffusion measurements appear as complementary techniques to investigate drug diffusion in skin.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"7 1","pages":"47-61"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-180179","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69857440","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 : 2018-01-01Epub Date: 2019-01-24DOI: 10.3233/BSI-180183
Michael J Knight, Robin A Damion, Risto A Kauppinen
Background and objective: Multiple factors including chemical composition and microstructure influence relaxivity of tissue water in vivo. We have quantified T1 in the human white mater (WM) together with diffusion tensor imaging to study a possible relationship between water T1, diffusional fractional anisotropy (FA) and fibre-to-field angle.
Methods: An inversion recovery (IR) pulse sequence with 6 inversion times for T1 and a multi-band diffusion tensor sequence with 60 diffusion sensitizing gradient directions for FA and the fibre-to-field angle θ (between the principal direction of diffusion and B0) were used at 3 Tesla in 40 healthy subjects. T1 was assessed using the method previously applied to anisotropy of coherence lifetime to provide a heuristic demonstration as a surface plot of T1 as a function of FA and the angle θ.
Results: Our data show that in the WM voxels with FA > 0.3 T1 becomes longer (i.e. 1/T1 = R1 slower) when fibre-to-field angle is 50-60°, approximating the magic angle of 54.7°. The longer T1 around the magic angle was found in a number of WM tracts independent of anatomy. S0 signal intensity, computed from IR fits, mirrored that of T1 being greater in the WM voxels when the fibre-to-field angle was 50-60°.
Conclusions: The current data point to fibre-to-field-angle dependent T1 relaxation in WM as an indication of effects of microstructure on the longitudinal relaxation of water.
{"title":"Observation of Angular Dependence of T1 in the Human White Matter at 3T.","authors":"Michael J Knight, Robin A Damion, Risto A Kauppinen","doi":"10.3233/BSI-180183","DOIUrl":"https://doi.org/10.3233/BSI-180183","url":null,"abstract":"<p><strong>Background and objective: </strong>Multiple factors including chemical composition and microstructure influence relaxivity of tissue water <i>in vivo.</i> We have quantified T1 in the human white mater (WM) together with diffusion tensor imaging to study a possible relationship between water T1, diffusional fractional anisotropy (FA) and fibre-to-field angle.</p><p><strong>Methods: </strong>An inversion recovery (IR) pulse sequence with 6 inversion times for T1 and a multi-band diffusion tensor sequence with 60 diffusion sensitizing gradient directions for FA and the fibre-to-field angle θ (between the principal direction of diffusion and B<sub>0</sub>) were used at 3 Tesla in 40 healthy subjects. T1 was assessed using the method previously applied to anisotropy of coherence lifetime to provide a heuristic demonstration as a surface plot of T1 as a function of FA and the angle θ.</p><p><strong>Results: </strong>Our data show that in the WM voxels with FA > 0.3 T1 becomes longer (i.e. 1/T1 = R1 slower) when fibre-to-field angle is 50-60°, approximating the magic angle of 54.7°. The longer T1 around the magic angle was found in a number of WM tracts independent of anatomy. S0 signal intensity, computed from IR fits, mirrored that of T1 being greater in the WM voxels when the fibre-to-field angle was 50-60°.</p><p><strong>Conclusions: </strong>The current data point to fibre-to-field-angle dependent T1 relaxation in WM as an indication of effects of microstructure on the longitudinal relaxation of water.</p>","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"7 3-4","pages":"125-133"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-180183","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37107005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy is a surface-sensitive and label-free technique, which is applied to obtain dynamic structural information of biomolecules. The study of proteins by ATR-FTIR spectroscopy can be impeded by their tendency to adsorb to solid surfaces. Furthermore, the adsorption process of proteins is often accompanied with conformational changes, which can interfere with the intended structural analysis. We efficiently modified a silicon ATR crystal surface with polyethylene glycol and thereby create a protein-repellent surface. To achieve a high sensitivity, which enables the study of small conformational changes of biomolecules, we combine surface passivation with specific immobilization. This is accomplished via the biotin-streptavidin interaction, which is one of the strongest known non-covalent protein-ligand interactions. As a proof of concept we present the specific immobilization of DNA. The modified surface is stable against elevated temperatures and 8 M urea and can therefore be used to study a wide range of biochemical systems and reactions. The surface chemistry is simple and performed under mild conditions, which leads to a high applicability of the presented approach.
{"title":"A combined approach of surface passivation and specific immobilization to study biomolecules by ATR-FTIR spectroscopy","authors":"Annika Krüger, A. Bürkle, A. Mangerich, K. Hauser","doi":"10.3233/BSI-180174","DOIUrl":"https://doi.org/10.3233/BSI-180174","url":null,"abstract":"Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy is a surface-sensitive and label-free technique, which is applied to obtain dynamic structural information of biomolecules. The study of proteins by ATR-FTIR spectroscopy can be impeded by their tendency to adsorb to solid surfaces. Furthermore, the adsorption process of proteins is often accompanied with conformational changes, which can interfere with the intended structural analysis. We efficiently modified a silicon ATR crystal surface with polyethylene glycol and thereby create a protein-repellent surface. To achieve a high sensitivity, which enables the study of small conformational changes of biomolecules, we combine surface passivation with specific immobilization. This is accomplished via the biotin-streptavidin interaction, which is one of the strongest known non-covalent protein-ligand interactions. As a proof of concept we present the specific immobilization of DNA. The modified surface is stable against elevated temperatures and 8 M urea and can therefore be used to study a wide range of biochemical systems and reactions. The surface chemistry is simple and performed under mild conditions, which leads to a high applicability of the presented approach.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"7 1","pages":"25-33"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-180174","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69857237","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. Schwaighofer, M. R. Alcaraz, J. Kuligowski, B. Lendl
: BACKGROUND: High emission powers of external cavity-quantum cascade laser (EC-QCL) light sources allow to employ significantly larger path lengths for infrared (IR) transmission measurements compared to conventional Fourier-transform infrared (FTIR) measurements employing thermal emitters. OBJECTIVE: An EC-QCL based IR transmission setup is presented as a viable alternative for analysis of proteins in both, academic protein structure studies as well as in process analytical applications. Here, the application of EC-QCL based IR transmission spectroscopy is introduced for i) monitoring of the protein secondary structure and ii) rapid screening of the thermal history of commercial milk samples without prior sample preparation. METHODS: Proteins present in milk were measured by QCL-IR and FTIR spectroscopy and spectra were compared. Dynamic conformational changes were followed by QCL-IR spectroscopy after chemical denaturation. Sixteen commercial milk samples were surveyed by QCL-IR spectroscopy and classified according to the experienced heat load during processing. RESULTS: The 4-5 times higher applicable transmission path length (38 µm for QCL vs. 8 µm for FTIR measurements) allows robust measurements of the protein amide I band in aqueous solutions. It was shown that IR spectra of the protein amide I band acquired by EC-QCL transmission spectroscopy are comparable to FTIR spectra and the acquired spectra were employed for the study of conformational changes in protein standard solutions. Furthermore, a classification analysis of commercial bovine milk samples based on their thermal history was accomplished. CONCLUSIONS: The potential application of EC-QCL IR spectroscopy was demonstrated as a tool for following conformational changes of the secondary protein structure as well as for fast screening for estimating the heat load applied to commercial milk.
{"title":"Recent advancements of EC-QCL based mid-IR transmission spectroscopy of proteins and application to analysis of bovine milk","authors":"A. Schwaighofer, M. R. Alcaraz, J. Kuligowski, B. Lendl","doi":"10.3233/BSI-180177","DOIUrl":"https://doi.org/10.3233/BSI-180177","url":null,"abstract":": BACKGROUND: High emission powers of external cavity-quantum cascade laser (EC-QCL) light sources allow to employ significantly larger path lengths for infrared (IR) transmission measurements compared to conventional Fourier-transform infrared (FTIR) measurements employing thermal emitters. OBJECTIVE: An EC-QCL based IR transmission setup is presented as a viable alternative for analysis of proteins in both, academic protein structure studies as well as in process analytical applications. Here, the application of EC-QCL based IR transmission spectroscopy is introduced for i) monitoring of the protein secondary structure and ii) rapid screening of the thermal history of commercial milk samples without prior sample preparation. METHODS: Proteins present in milk were measured by QCL-IR and FTIR spectroscopy and spectra were compared. Dynamic conformational changes were followed by QCL-IR spectroscopy after chemical denaturation. Sixteen commercial milk samples were surveyed by QCL-IR spectroscopy and classified according to the experienced heat load during processing. RESULTS: The 4-5 times higher applicable transmission path length (38 µm for QCL vs. 8 µm for FTIR measurements) allows robust measurements of the protein amide I band in aqueous solutions. It was shown that IR spectra of the protein amide I band acquired by EC-QCL transmission spectroscopy are comparable to FTIR spectra and the acquired spectra were employed for the study of conformational changes in protein standard solutions. Furthermore, a classification analysis of commercial bovine milk samples based on their thermal history was accomplished. CONCLUSIONS: The potential application of EC-QCL IR spectroscopy was demonstrated as a tool for following conformational changes of the secondary protein structure as well as for fast screening for estimating the heat load applied to commercial milk.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"7 1","pages":"35-45"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-180177","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69857318","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}
{"title":"Two-dimensional infrared (2D IR) spectroscopy for elucidating ion occupancies in the selectivity filter of ion channels1","authors":"H. Kratochvil, M. Zanni","doi":"10.3233/BSI-180175","DOIUrl":"https://doi.org/10.3233/BSI-180175","url":null,"abstract":"","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"7 1","pages":"3-15"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-180175","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69857299","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}