Pub Date : 2025-03-21DOI: 10.1016/j.ssnmr.2025.102003
Patrick C.A. van der Wel , Tuo Wang
{"title":"Editorial: Solid-state NMR and DNP of heterogeneous biomaterials and cellular systems","authors":"Patrick C.A. van der Wel , Tuo Wang","doi":"10.1016/j.ssnmr.2025.102003","DOIUrl":"10.1016/j.ssnmr.2025.102003","url":null,"abstract":"","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"137 ","pages":"Article 102003"},"PeriodicalIF":1.8,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.ssnmr.2025.102002
Loic Delcourte , Mélanie Berbon , Marion Rodriguez , Laurence Delhaes , Birgit Habenstein , Antoine Loquet
Chitin is the most important nitrogen-containing polysaccharide found on Earth. This polysaccharide is a polymer of an N-acetylglucosamine and it is a crucial structural component of fungal cell walls and crustaceans. Magic-angle spinning solid-state NMR is emerging as a powerful analytical approach to study polysaccharides in the context of intact cell walls and whole cells. The presence of an acetamido group in chitin is attractive for 15N solid-state NMR. Here we investigate the use of various multi-step polarization transfer experiments incorporating indirect 15N detection at moderate spinning frequency, adapted from pulse sequences commonly employed for residue resonance assignment in biosolid proteins. The 13C,15N chitin spin topology slightly differs from amino acids, and we discussed the use of frequency-selective 15N-13C cross-polarization transfers followed by broadband or frequency-selective homonuclear 13C–13C transfers to detect chitin resonances. Demonstrated here for chitin found in the cell wall of the fungus Aspergillus fumigatus, the use of indirect 15N detection through multi-step polarization transfers could be advantageous to investigate more complex nitrogen-containing polysaccharides found in whole cells and peptidoglycan samples.
{"title":"Solid-state NMR observation of chitin in whole cells by indirect 15N detection with NC, NCC, CNC and CNCC polarization transfers","authors":"Loic Delcourte , Mélanie Berbon , Marion Rodriguez , Laurence Delhaes , Birgit Habenstein , Antoine Loquet","doi":"10.1016/j.ssnmr.2025.102002","DOIUrl":"10.1016/j.ssnmr.2025.102002","url":null,"abstract":"<div><div>Chitin is the most important nitrogen-containing polysaccharide found on Earth. This polysaccharide is a polymer of an N-acetylglucosamine and it is a crucial structural component of fungal cell walls and crustaceans. Magic-angle spinning solid-state NMR is emerging as a powerful analytical approach to study polysaccharides in the context of intact cell walls and whole cells. The presence of an acetamido group in chitin is attractive for <sup>15</sup>N solid-state NMR. Here we investigate the use of various multi-step polarization transfer experiments incorporating indirect <sup>15</sup>N detection at moderate spinning frequency, adapted from pulse sequences commonly employed for residue resonance assignment in biosolid proteins. The <sup>13</sup>C,<sup>15</sup>N chitin spin topology slightly differs from amino acids, and we discussed the use of frequency-selective <sup>15</sup>N-<sup>13</sup>C cross-polarization transfers followed by broadband or frequency-selective homonuclear <sup>13</sup>C–<sup>13</sup>C transfers to detect chitin resonances. Demonstrated here for chitin found in the cell wall of the fungus <em>Aspergillus fumigatus</em>, the use of indirect <sup>15</sup>N detection through multi-step polarization transfers could be advantageous to investigate more complex nitrogen-containing polysaccharides found in whole cells and peptidoglycan samples.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"137 ","pages":"Article 102002"},"PeriodicalIF":1.8,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143675577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-21DOI: 10.1016/j.ssnmr.2025.101994
Jacob Mayer , Frédéric A. Perras
Probing the fast dynamics of surface sites using NMR spectroscopy is highly challenging owing to the sites' high dilution and the difficulties often associated with isotopic enrichment. Intra-CH21H–1H dipolar couplings are ideal probes of motions given that they only involve 1H's and the tensor has a well-defined size and orientation. We introduce a frequency-selective variant of the double-quantum sideband method to measure like-spin 1H–1H dipolar coupling constants. The experiment dramatically reduces the instrument time required to measure dynamically-averaged intra-CH2 dipolar couplings. We demonstrate the performance of the sequence using silica-supported silanes as model highly-mobile surface species.
{"title":"Highly sensitive measurements of methylene dynamics with a frequency-selective double-quantum sideband method","authors":"Jacob Mayer , Frédéric A. Perras","doi":"10.1016/j.ssnmr.2025.101994","DOIUrl":"10.1016/j.ssnmr.2025.101994","url":null,"abstract":"<div><div>Probing the fast dynamics of surface sites using NMR spectroscopy is highly challenging owing to the sites' high dilution and the difficulties often associated with isotopic enrichment. Intra-CH<sub>2</sub> <sup>1</sup>H–<sup>1</sup>H dipolar couplings are ideal probes of motions given that they only involve <sup>1</sup>H's and the tensor has a well-defined size and orientation. We introduce a frequency-selective variant of the double-quantum sideband method to measure like-spin <sup>1</sup>H–<sup>1</sup>H dipolar coupling constants. The experiment dramatically reduces the instrument time required to measure dynamically-averaged intra-CH<sub>2</sub> dipolar couplings. We demonstrate the performance of the sequence using silica-supported silanes as model highly-mobile surface species.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"136 ","pages":"Article 101994"},"PeriodicalIF":1.8,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143510732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-04DOI: 10.1016/j.ssnmr.2025.101993
Neethu Thomas , Claire Welton , Tomasz Pawlak , Parth Raval , Julien Trébosc , Sheetal K. Jain , G.N. Manjunatha Reddy
A cross-polarization 2H–1H isotope correlation spectroscopy (CP-iCOSY) approach is presented for characterizing a deuterated amino acid, pharmaceutical compound and a solid formulation. This can be achieved by isotopic enrichment in conjunction with high magnetic field (28.2 T) and fast magic-angle spinning (MAS), enabling the rapid detection of 2H NMR spectra in a few seconds to minutes. Specifically, two-dimensional (2D) 2H–1H CP-iCOSY experiment allows the local structures and through-space interactions in a partially deuterated compounds to be elucidated. In doing so, we compare conventional spin-lock and rotor-echo-short-pulse-irradiation RESPIRATIONCP sequences for acquiring 2D 1H–2H correlation spectra. The RESPIRATIONCP sequence allows the detection of 2D peaks at lower CP contact times (0.1–1 ms) than the conventional CP (0.2–4 ms) sequence. Analysis of partially deuterated L-histidine·HCl·H2O and dopamine.HCl is presented, in which the detection of 2D peaks corresponding to 2H–1H pairs separated by greater than 4 Å distance demonstrates the potential of the presented approach for the characterization of packing interactions. These results are corroborated by NMR crystallography analysis using the Gauge-Including Projector Augmented-Wave (GIPAW) approach.
{"title":"Deuteron-proton isotope correlation spectroscopy at high magnetic fields","authors":"Neethu Thomas , Claire Welton , Tomasz Pawlak , Parth Raval , Julien Trébosc , Sheetal K. Jain , G.N. Manjunatha Reddy","doi":"10.1016/j.ssnmr.2025.101993","DOIUrl":"10.1016/j.ssnmr.2025.101993","url":null,"abstract":"<div><div>A cross-polarization <sup>2</sup>H–<sup>1</sup>H isotope correlation spectroscopy (CP-iCOSY) approach is presented for characterizing a deuterated amino acid, pharmaceutical compound and a solid formulation. This can be achieved by isotopic enrichment in conjunction with high magnetic field (28.2 T) and fast magic-angle spinning (MAS), enabling the rapid detection of <sup>2</sup>H NMR spectra in a few seconds to minutes. Specifically, two-dimensional (2D) <sup>2</sup>H–<sup>1</sup>H CP-iCOSY experiment allows the local structures and through-space interactions in a partially deuterated compounds to be elucidated. In doing so, we compare conventional spin-lock and rotor-echo-short-pulse-irradiation <sup>RESPIRATION</sup>CP sequences for acquiring 2D <sup>1</sup>H–<sup>2</sup>H correlation spectra. The <sup>RESPIRATION</sup>CP sequence allows the detection of 2D peaks at lower CP contact times (0.1–1 ms) than the conventional CP (0.2–4 ms) sequence. Analysis of partially deuterated L-histidine·HCl·H<sub>2</sub>O and dopamine.HCl is presented, in which the detection of 2D peaks corresponding to <sup>2</sup>H–<sup>1</sup>H pairs separated by greater than 4 Å distance demonstrates the potential of the presented approach for the characterization of packing interactions. These results are corroborated by NMR crystallography analysis using the Gauge-Including Projector Augmented-Wave (GIPAW) approach.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"136 ","pages":"Article 101993"},"PeriodicalIF":1.8,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143418551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.ssnmr.2024.101984
Jan Blahut , Zdeněk Tošner
Exciting developments in new experimental methods for multidimensional solid-state NMR spectroscopy have recently been achieved using optimal-control theory. These results, in turn, have triggered the development of new pulse sequences based on traditional analytical theories. This trend article summarises the key steps leading to these advancements. It also describes additional applications of optimal control beyond structural biology and envisions similar progress in the NMR of solid materials. Despite attractive features of optimal-control pulse sequences demonstrated in the proof-of-concept studies, their experimental utilization remains sparse, probably due to the lack of awareness among experimentalists. We hope this mini-review helps to spread optimal-control methods into routine experimental workflows. Furthermore, we offer a personal outlook on how numerical optimisations could in general enhance the experimental capabilities of solid-state NMR in the near future, with optimal control serving as a pioneer exploring new possibilities.
{"title":"Optimal control: From sensitivity improvement to alternative pulse-sequence design in solid-state NMR","authors":"Jan Blahut , Zdeněk Tošner","doi":"10.1016/j.ssnmr.2024.101984","DOIUrl":"10.1016/j.ssnmr.2024.101984","url":null,"abstract":"<div><div>Exciting developments in new experimental methods for multidimensional solid-state NMR spectroscopy have recently been achieved using optimal-control theory. These results, in turn, have triggered the development of new pulse sequences based on traditional analytical theories. This trend article summarises the key steps leading to these advancements. It also describes additional applications of optimal control beyond structural biology and envisions similar progress in the NMR of solid materials. Despite attractive features of optimal-control pulse sequences demonstrated in the proof-of-concept studies, their experimental utilization remains sparse, probably due to the lack of awareness among experimentalists. We hope this mini-review helps to spread optimal-control methods into routine experimental workflows. Furthermore, we offer a personal outlook on how numerical optimisations could in general enhance the experimental capabilities of solid-state NMR in the near future, with optimal control serving as a pioneer exploring new possibilities.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"135 ","pages":"Article 101984"},"PeriodicalIF":1.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142915579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The naturally abundant 14N isotope (>99 %) is sparingly employed for characterization in solid-state nuclear magnetic resonance (NMR) despite the importance of nitrogen atoms in shaping molecular structures and properties. This inhibition can be attributed to large quadrupolar couplings (∼several MHz), resulting in more involved spin methodologies for 14N nuclei. Experimentally, spin-½ nuclei are utilized for excitation and detection through two-way (1H→14N→1H) polarization transfer between spin-½ nuclei and 14N. Herein, we show direct 14N spin excitation followed by 14N→1H cross-polarization (CP) is an efficient method for polarization transfer even for 14N spins with a large quadrupolar coupling constant (3–4 MHz). This contrasts previous studies, which indicate that 1H-14N spectra can only be observed with a pair of at least a rotor period-long symmetric 14N pulses (J. Chem. Phys. 151 (2019) 154202). The 14N→1H CP spin dynamics have been experimentally established and can be explained in analogy to spin-½ Hartmann-Hahn CP if visualized in the quadrupolar jolting frame. The 14N→1H CP is ∼1.9–2.7 times more efficient in polarization transfer than other 14N edited experiments. Considering shorter 14N T1 relaxation times compared to protons, 14N edited spectra were recorded using 14N→1H CP, resulting in enhanced sensitivity per unit of time.
{"title":"Spin-dynamics and efficiency of single 14N-1H cross-polarization at fast magic angle spinning in solids","authors":"Vipin Agarwal , Sreejith Raran-Kurussi , Yusuke Nishiyama","doi":"10.1016/j.ssnmr.2025.101992","DOIUrl":"10.1016/j.ssnmr.2025.101992","url":null,"abstract":"<div><div>The naturally abundant <sup>14</sup>N isotope (>99 %) is sparingly employed for characterization in solid-state nuclear magnetic resonance (NMR) despite the importance of nitrogen atoms in shaping molecular structures and properties. This inhibition can be attributed to large quadrupolar couplings (∼several MHz), resulting in more involved spin methodologies for <sup>14</sup>N nuclei. Experimentally, spin-½ nuclei are utilized for excitation and detection through two-way (<sup>1</sup>H→<sup>14</sup>N→<sup>1</sup>H) polarization transfer between spin-½ nuclei and <sup>14</sup>N. Herein, we show direct <sup>14</sup>N spin excitation followed by <sup>14</sup>N→<sup>1</sup>H cross-polarization (CP) is an efficient method for polarization transfer even for <sup>14</sup>N spins with a large quadrupolar coupling constant (3–4 MHz). This contrasts previous studies, which indicate that <sup>1</sup>H-<sup>14</sup>N spectra can only be observed with a pair of at least a rotor period-long symmetric <sup>14</sup>N pulses (<em>J. Chem. Phys. 151</em> (2019) <em>154202</em>). The <sup>14</sup>N→<sup>1</sup>H CP spin dynamics have been experimentally established and can be explained in analogy to spin-½ Hartmann-Hahn CP if visualized in the quadrupolar jolting frame. The <sup>14</sup>N→<sup>1</sup>H CP is ∼1.9–2.7 times more efficient in polarization transfer than other <sup>14</sup>N edited experiments. Considering shorter <sup>14</sup>N T<sub>1</sub> relaxation times compared to protons, <sup>14</sup>N edited spectra were recorded using <sup>14</sup>N→<sup>1</sup>H CP, resulting in enhanced sensitivity per unit of time.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"136 ","pages":"Article 101992"},"PeriodicalIF":1.8,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143376888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cellulose–lignin blends are proposed as alternative precursors for carbon fiber (CF) production, offering a potential sustainable and cost-effective alternative to the expensive fossil-based polymers currently used. The characteristics of the precursor fibers including their crystallinity, the incorporated chemical structures and the distribution of the biopolymers have a significant influence on their carbonization behavior and the properties of the CFs. They are partly determined by the composition of the bio-based resources and the conditions used during the fiber fixation, i.e. the coagulation, an important processing step. In this work, 13C solid and 2D solution NMR methodologies were applied to investigate the impact of coagulation and thermostabilization conditions on cellulose and cellulose-lignin blends using a thin film model. Solid state NMR spectroscopy showed that the choice of the anti-solvent influenced the proportion of cellulose II versus amorphous regions in the coagulated films. Independent of the presence of lignin, the choice of anti-solvent seems to impact the rate of thermal reactions. After thermostabilization at 245 °C, the samples were investigated using a solution NMR protocol devised for cellulosic materials. At 275 °C, most of the samples became insoluble for solution NMR. However, solid state NMR revealed further changes in the chemical composition, which were dependent on both the presence of lignin and the choice of anti-solvent. This multi-faceted approach combining solid state and 2D solution NMR techniques provides a comprehensive understanding of the cellulose structure and the products formed for cellulose-lignin-based CFs, which is crucial for optimizing their properties and potential applications.
纤维素-木质素混合物被提议作为碳纤维（CF）生产的替代前体，为目前使用的昂贵化石基聚合物提供了一种潜在的可持续且具有成本效益的替代品。前体纤维的特性，包括其结晶度、结合的化学结构和生物聚合物的分布，对其碳化行为和碳纤维的特性有重大影响。它们在一定程度上取决于生物基资源的成分以及纤维固定（即凝固）过程中使用的条件，凝固是一个重要的加工步骤。在这项工作中，采用了 13C 固态和二维溶液 NMR 方法，利用薄膜模型研究了凝固和热稳定条件对纤维素和纤维素-木质素混合物的影响。固态核磁共振光谱显示，反溶剂的选择会影响凝固薄膜中纤维素 II 与无定形区域的比例。与木质素的存在无关，反溶剂的选择似乎会影响热反应的速度。在 245 °C 下进行热稳定后，使用针对纤维素材料设计的溶液 NMR 方案对样品进行了研究。在 275 °C 时，大多数样品变得不溶于溶液 NMR。然而，固态 NMR 揭示了化学成分的进一步变化，这些变化取决于木质素的存在和反溶剂的选择。这种将固态和二维溶液 NMR 技术相结合的多层面方法提供了对纤维素结构以及纤维素-木质素基 CF 所形成产物的全面了解，这对于优化其性能和潜在应用至关重要。
{"title":"Applications of NMR based methodologies investigating the behavior of lignin and cellulose towards bio-based carbon fibers production","authors":"Feryal Guerroudj , Lukas Fliri , Jenny Bengtsson , Leandro Cid Gomes , Tristan Gazzola , Michael Hummel , Diana Bernin","doi":"10.1016/j.ssnmr.2024.101977","DOIUrl":"10.1016/j.ssnmr.2024.101977","url":null,"abstract":"<div><div>Cellulose–lignin blends are proposed as alternative precursors for carbon fiber (CF) production, offering a potential sustainable and cost-effective alternative to the expensive fossil-based polymers currently used. The characteristics of the precursor fibers including their crystallinity, the incorporated chemical structures and the distribution of the biopolymers have a significant influence on their carbonization behavior and the properties of the CFs. They are partly determined by the composition of the bio-based resources and the conditions used during the fiber fixation, i.e. the coagulation, an important processing step. In this work, <sup>13</sup>C solid and 2D solution NMR methodologies were applied to investigate the impact of coagulation and thermostabilization conditions on cellulose and cellulose-lignin blends using a thin film model. Solid state NMR spectroscopy showed that the choice of the anti-solvent influenced the proportion of cellulose II <em>versus</em> amorphous regions in the coagulated films. Independent of the presence of lignin, the choice of anti-solvent seems to impact the rate of thermal reactions. After thermostabilization at 245 °C, the samples were investigated using a solution NMR protocol devised for cellulosic materials. At 275 °C, most of the samples became insoluble for solution NMR. However, solid state NMR revealed further changes in the chemical composition, which were dependent on both the presence of lignin and the choice of anti-solvent. This multi-faceted approach combining solid state and 2D solution NMR techniques provides a comprehensive understanding of the cellulose structure and the products formed for cellulose-lignin-based CFs, which is crucial for optimizing their properties and potential applications.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"134 ","pages":"Article 101977"},"PeriodicalIF":1.8,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-20DOI: 10.1016/j.ssnmr.2024.101976
Liliya Vugmeyster , Riqiang Fu , Dmitry Ostrovsky
17O NMR methods are emerging as a powerful tool for determination of structure and dynamics in materials and biological solids. We present experimental and theoretical frameworks for measurements of 17O NMR relaxation times in static solids focusing on the excitation of the central transition of the 17O spin 5/2 system. We employ 17O-enriched NaNO3 as a model compound, in which the nitrate oxygen atoms undergo 3-fold jumps. Rotating frame (), transverse () and longitudinal () relaxation times as well as line shapes were measured for the central transition in the 280 to 195 K temperature range at 14.1 and 18.8 T field strengths. We conduct experimental and theoretical comparison between different relaxation methods and demonstrate the advantage of combining data from multiple relaxation time and line shape measurements to obtain a more accurate determination of the dynamics as compared to either of the techniques alone. The computational framework for relaxation of spin 5/2 nuclei is developed using the numerical integration of the Liouville − von Neumann equation.
{"title":"17O NMR relaxation measurements for investigation of molecular dynamics in static solids using sodium nitrate as a model compound","authors":"Liliya Vugmeyster , Riqiang Fu , Dmitry Ostrovsky","doi":"10.1016/j.ssnmr.2024.101976","DOIUrl":"10.1016/j.ssnmr.2024.101976","url":null,"abstract":"<div><div><sup>17</sup>O NMR methods are emerging as a powerful tool for determination of structure and dynamics in materials and biological solids. We present experimental and theoretical frameworks for measurements of <sup>17</sup>O NMR relaxation times in static solids focusing on the excitation of the central transition of the <sup>17</sup>O spin 5/2 system. We employ <sup>17</sup>O-enriched NaNO<sub>3</sub> as a model compound, in which the nitrate oxygen atoms undergo 3-fold jumps. Rotating frame (<span><math><mrow><msub><mi>T</mi><mrow><mn>1</mn><mi>ρ</mi></mrow></msub></mrow></math></span>), transverse (<span><math><mrow><msub><mi>T</mi><mn>2</mn></msub></mrow></math></span>) and longitudinal (<span><math><mrow><msub><mi>T</mi><mn>1</mn></msub></mrow></math></span>) relaxation times as well as line shapes were measured for the central transition in the 280 to 195 K temperature range at 14.1 and 18.8 T field strengths. We conduct experimental and theoretical comparison between different relaxation methods and demonstrate the advantage of combining data from multiple relaxation time and line shape measurements to obtain a more accurate determination of the dynamics as compared to either of the techniques alone. The computational framework for relaxation of spin 5/2 nuclei is developed using the numerical integration of the Liouville − von Neumann equation.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"134 ","pages":"Article 101976"},"PeriodicalIF":1.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142691155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-25DOI: 10.1016/j.ssnmr.2024.101975
Kathy Duong , Evan Moss , Courtney Reichhardt
People with the genetic disease cystic fibrosis (CF) often have chronic airway infections and produce airway secretions called sputum. A better understanding of sputum composition is desired in order to track changes in response to CF therapeutics and to improve laboratory models for the study of CF airway infections. The glycosylated protein mucin is a primary component. Along with extracellular DNA, mucin gives rise to the high viscoelasticity of sputum, which inhibits airway clearance and is thought to promote chronic airway infections in people with CF. Past studies of sputum composition identified additional biomolecular components of sputum including other proteins, both glycosylated and not glycosylated, free amino acids, and lipids. Typically, studies of sputum, as well as other complex biological materials, have focused on soluble or isolated components. Solid-state NMR is not limited to the study of soluble components. Instead, it can provide molecular-level information about insoluble biological samples. Additionally, solid-state NMR can provide information about sample composition without requiring any processing of the sample, eliminating the possibility of misestimating certain components due to insolubility or potential sample loss in isolation steps. In this study, we used both 13C and 31P CPMAS to investigate the total composition of sputum samples obtained from six people with CF. We compared these spectra to those of commercially available mucin, DNA, and phospholipid samples. Lastly, we performed complementary biochemical analyses to identify specific proteins present in the sputum samples. Overall, our findings provide insight into the composition of unprocessed sputum samples from people with CF, which can be used as a benchmark for future investigations of CF and infections in the airways of people with CF. Further, this study provides opportunities to expand the solid-state NMR approach to include dynamic nuclear polarization (DNP) to obtain high-resolution information of sputum and similar biological samples that are not feasible to isotopically enrich.
{"title":"Solid-state NMR compositional analysis of sputum from people with cystic fibrosis","authors":"Kathy Duong , Evan Moss , Courtney Reichhardt","doi":"10.1016/j.ssnmr.2024.101975","DOIUrl":"10.1016/j.ssnmr.2024.101975","url":null,"abstract":"<div><div>People with the genetic disease cystic fibrosis (CF) often have chronic airway infections and produce airway secretions called sputum. A better understanding of sputum composition is desired in order to track changes in response to CF therapeutics and to improve laboratory models for the study of CF airway infections. The glycosylated protein mucin is a primary component. Along with extracellular DNA, mucin gives rise to the high viscoelasticity of sputum, which inhibits airway clearance and is thought to promote chronic airway infections in people with CF. Past studies of sputum composition identified additional biomolecular components of sputum including other proteins, both glycosylated and not glycosylated, free amino acids, and lipids. Typically, studies of sputum, as well as other complex biological materials, have focused on soluble or isolated components. Solid-state NMR is not limited to the study of soluble components. Instead, it can provide molecular-level information about insoluble biological samples. Additionally, solid-state NMR can provide information about sample composition without requiring any processing of the sample, eliminating the possibility of misestimating certain components due to insolubility or potential sample loss in isolation steps. In this study, we used both <sup>13</sup>C and <sup>31</sup>P CPMAS to investigate the total composition of sputum samples obtained from six people with CF. We compared these spectra to those of commercially available mucin, DNA, and phospholipid samples. Lastly, we performed complementary biochemical analyses to identify specific proteins present in the sputum samples. Overall, our findings provide insight into the composition of unprocessed sputum samples from people with CF, which can be used as a benchmark for future investigations of CF and infections in the airways of people with CF. Further, this study provides opportunities to expand the solid-state NMR approach to include dynamic nuclear polarization (DNP) to obtain high-resolution information of sputum and similar biological samples that are not feasible to isotopically enrich.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"134 ","pages":"Article 101975"},"PeriodicalIF":1.8,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142569403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-14DOI: 10.1016/j.ssnmr.2024.101974
Christine Chrissian , Michael L. Stawski , Andrew P. Williams , Ruth E. Stark
Among the many natural biomaterials for which information on atomic-level structure and reorientational motion can offer essential clues to function, insoluble multi-component composites with limited degrees of order are among the most challenging to study. Despite its limited sensitivity, solid-state NMR (ssNMR) is often the technique of choice to ferret out these details in carbon- and nitrogen-rich materials: this spectroscopic approach can probe many biomaterials in their native or near-native states, either with or without the introduction of stable NMR-active isotopes, or with the assistance of dynamic nuclear polarization technology. During a span of close to four decades, such research targets and ssNMR approaches have been exemplified by insects, a diverse and evolutionarily agile group of organisms with global impacts that include ecology, agriculture, and human disease. In this short review, we present case studies on insect cuticles that range from protective exoskeletons and egg capsules to the wing structures that enable flight and showcase nature's awe-inspiring beauty, highlighting the use of ssNMR spectroscopy to profile chemical composition, elucidate macromolecular architecture, and monitor metabolic development in these fascinating biological assemblies.
{"title":"Elucidating structure and metabolism of insect biomaterials by solid-state NMR","authors":"Christine Chrissian , Michael L. Stawski , Andrew P. Williams , Ruth E. Stark","doi":"10.1016/j.ssnmr.2024.101974","DOIUrl":"10.1016/j.ssnmr.2024.101974","url":null,"abstract":"<div><div>Among the many natural biomaterials for which information on atomic-level structure and reorientational motion can offer essential clues to function, insoluble multi-component composites with limited degrees of order are among the most challenging to study. Despite its limited sensitivity, solid-state NMR (ssNMR) is often the technique of choice to ferret out these details in carbon- and nitrogen-rich materials: this spectroscopic approach can probe many biomaterials in their native or near-native states, either with or without the introduction of stable NMR-active isotopes, or with the assistance of dynamic nuclear polarization technology. During a span of close to four decades, such research targets and ssNMR approaches have been exemplified by insects, a diverse and evolutionarily agile group of organisms with global impacts that include ecology, agriculture, and human disease. In this short review, we present case studies on insect cuticles that range from protective exoskeletons and egg capsules to the wing structures that enable flight and showcase nature's awe-inspiring beauty, highlighting the use of ssNMR spectroscopy to profile chemical composition, elucidate macromolecular architecture, and monitor metabolic development in these fascinating biological assemblies.</div></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":"134 ","pages":"Article 101974"},"PeriodicalIF":1.8,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142508285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号