Article
Chemistry, Analytical
Alan Wong
Summary: High-Resolution Magic-Angle Spinning (HRMAS) NMR spectroscopy is considered an essential technique in metabolomics for assessing the biochemical composition of tissue samples. HRMAS localized profiling shows promise for spatial resolution of metabolic profiles within the sampling tissues.
ANALYTICAL METHODS
(2023)
Article
Chemistry, Physical
Sangeeth Das Kallullathil, Tucker Carrington Jr
Summary: In this paper, the authors propose the use of the CP-MSBII eigensolver and a contraction tree to calculate vibrational spectra. The CP-MSBII eigensolver utilizes the CP format, which has a linear memory cost with respect to the number of coordinates. By breaking down the full problem into smaller sub-problems and using a contraction tree, the required rank for each sub-problem becomes small. The authors demonstrate the effectiveness of their approach by computing the vibrational energy levels of acetonitrile and ethylene oxide.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Sangeeth Das Kallullathil, Tucker Carrington
Summary: This paper discusses a method that uses the canonical polyadic (CP) format to compute vibrational energy levels of polyatomic molecules by constructing a basis from vectors obtained by solving linear equations. The approach eliminates the need to generate tensors with a rank higher than the fixed rank used to solve the linear equations, without requiring rank reduction or orthogonalization.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Review
Biophysics
Leo L. Cheng
Summary: This article provides a history of the discovery and recent developments of high-resolution magic angle spinning (HRMAS) NMR, a technique used for intact biological material analysis. HRMAS NMR metabolomics studies have been applied in various fields such as human disease states, plant and food analysis, and cell structure studies. The article also discusses the potential applications of HRMAS NMR in future biomedical investigations.
NMR IN BIOMEDICINE
(2023)
Article
Physics, Multidisciplinary
Haoyu Guan, Wenxian Zhang
Summary: The translation introduces a numerical method for quantum many-body systems and verifies its efficiency and accuracy through calculations on Ising spin chains and spin glass shards. The method is significantly faster than the state-of-the-art methods for computing interior eigenvalues and is suitable for large-scale eigenvalue computations.
Article
Biochemistry & Molecular Biology
Marta Bonaccorsi, Tanguy Le Marchand, Guido Pintacuda
Summary: Magic-Angle Spinning Nuclear Magnetic Resonance (MAS NMR) is a rapidly developing technique that complements solution NMR, X-ray crystallography, and electron microscopy for the biophysical characterization of microcrystalline, poorly crystalline or disordered protein samples. MAS NMR is ideal for investigating both structures and dynamics, and has been increasingly applied in structural biology research in recent years to describe conformational dynamics in various systems.
CURRENT OPINION IN STRUCTURAL BIOLOGY
(2021)
Review
Chemistry, Physical
Bianca Chandler, Lauren Todd, Steven O. Smith
Summary: G protein-coupled receptors (GPCRs) are a class of transmembrane proteins with a simple structure that can recognize diverse chemical signals. There are over 800 GPCRs encoded in the human genome, serving as receptors for vision, smell, taste, and other physiological processes. While protein crystallography and electron cryo-microscopy have provided high-resolution structures of GPCRs, the structural changes induced by ligand or drug binding to stabilize active or inactive conformations are often subtle. NMR spectroscopy can provide insights into the local structure, dynamics, and activation pathways of GPCRs, capturing intermediate states and low-population conformations. Solid-state magic angle spinning NMR has been used to study the structure and activation mechanisms of GPCRs, particularly in the diverse class A family. This review highlights the application of solid-state and solution-state NMR spectroscopy in understanding the activation of different GPCR classes and subfamilies by their ligands and the modulation of GPCR activation by small molecule drugs. (c) 2021 Elsevier B.V. All rights reserved.
PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY
(2022)
Article
Biochemical Research Methods
Andrea Bertarello, Pierrick Berruyer, Urban Skantze, Samiksha Sardana, Malvika Sardana, Charles S. Elmore, Markus Schade, Elisabetta Chiarparin, Staffan Schantz, Lyndon Emsley
Summary: Dynamic nuclear polarization (DNP) significantly enhances the sensitivity of MAS NMR, but cross polarization (CP) is usually not quantitative. Research shows that absolute quantification in MAS DNP NMR is possible under DNP conditions, with errors below 10%.
JOURNAL OF MAGNETIC RESONANCE
(2021)
Review
Radiology, Nuclear Medicine & Medical Imaging
Matteo Sanchez-Dahl Gonzalez, Isabella H. Muti, Leo L. Cheng
Summary: This review discusses the potential clinical benefits of incorporating high-resolution magic angle spinning magnetic resonance spectroscopy in the diagnosis, prognostication, and monitoring of prostate cancer.
MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE
(2022)
Article
Biochemical Research Methods
Daniel Banks, Brian Michael, Natalie Golota, Robert G. Griffin
Summary: This paper discusses the use of 3D printing and rapid prototyping methods to fabricate 3.2 mm stators and drive caps for NMR experiments. With the assistance of CAD software, these components can be produced at a fraction of the cost of commercial parts, while demonstrating comparable performance to commercially available systems.
JOURNAL OF MAGNETIC RESONANCE
(2022)
Article
Biochemical Research Methods
Evgeny Nimerovsky, Stefan Becker, Loren B. Andreas
Summary: In this study, we investigate the windowed sequence for cross polarization (wCP) and find that it has additional matching conditions compared to traditional cross polarization. By considering the flip angle of the pulse, we observe a striking similarity between wCP and CP transfer conditions. Using spin-1/2 formalism and average Hamiltonian theory, we derive an analytical approximation that matches these observed transfer conditions. Data recorded at spectrometers with different external magnetic fields show that these transfers and the selectivity of CP are related to flip angle (average nutation).
JOURNAL OF MAGNETIC RESONANCE
(2023)
Review
Chemistry, Physical
Kai Xue, Riddhiman Sarkar, Zdenek Tosner, Bernd Reif
Summary: Proton detection in solid state NMR is continuously advancing, and current achievements include the necessity of deuteration for optimal spectral quality, the superiority of 13CH3 isotopomers for methyl groups at high MAS frequencies, and the sensitivity enhancement with increased static magnetic field.
PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY
(2022)
Article
Chemistry, Physical
Debashis Majhi, Boris B. Kharkov, Sergey Dvinskikh
Summary: Dipolar NMR spectroscopy is a powerful analytical tool for studying structural and dynamic properties of solids at the molecular level. An approach to determine the signs of dipolar couplings in liquid crystals is presented, where sign information can be directly obtained from one-dimensional NMR spectra in samples spinning slightly off the magic angle. This method can be used to develop an experimental strategy for sign-sensitive measurements of heteronuclear dipolar couplings in anisotropic soft materials.
CHEMICAL PHYSICS LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Suochang Xu, Nicholas R. Jaegers, Wenda Hu, Ja Hun Kwak, Xinhe Bao, Junming Sun, Yong Wang, Jian Zhi Hu
Summary: In this study, detailed analysis of three aluminum oxide phases was conducted using high-field NMR, revealing structural information of different aluminum sites and providing a method to quantify complex mixtures of aluminum sites in transition alumina samples. The results showcase the potential of high-field NMR in characterizing materials and identifying distinct phases within a sample.
Article
Chemistry, Analytical
Emma Kitchner, Michael Seung, Jose Chavez, Luca Ceresa, Joseph Kimball, Ignacy Gryczynski, Zygmunt Gryczynski
Summary: This report discusses the impact of excitation and emission conditions on fluorescence measurements and emphasizes the importance of correcting observation conditions. The necessity of using total fluorescence intensity or intensity measured under magic angle conditions for both steady-state and time-resolved fluorescence measurements is demonstrated, as well as the dependence of lifetime measurements on observation wavelengths.
METHODS AND APPLICATIONS IN FLUORESCENCE
(2022)
Review
Physics, Multidisciplinary
Tiago Bueno Moraes, Luiz Alberto Colnago
Summary: In the past two decades, noninvasive physical methods based on electromagnetic radiation have been developed to evaluate food quality. Nuclear magnetic resonance (NMR), which does not use ionizing radiation and is not strongly attenuated by food or package composition, can be used for noninvasive analysis of intact and packaged foods. However, high-resolution NMR instruments are expensive and bulky, limiting their practical application. Therefore, low-cost, low-field, time-domain NMR instruments (TD-NMR) have been used for noninvasive analysis of intact food.
BRAZILIAN JOURNAL OF PHYSICS
(2022)
Article
Biochemistry & Molecular Biology
Marilia Vilela Salvador, Flavio Vinicius Crizostomo Kock, Isabella Laporte Santos, Jean Fausto Carvalho Paulino, Caleo Panhoca de Almeida, Rodrigo Henrique dos Santos Garcia, Luciana Lasry Benchimol-Reis, Luiz Alberto Colnago, Antonio Gilberto Ferreira
Summary: The use of UV-C cool white light on bean seeds increases seed coat darkening while preserving seed germination. In this study, the effect of UV-C light on different bean genotypes was monitored using NMR spectroscopy. The results indicate that the darkening occurs on the seed coat and is primarily influenced by the metabolite phenylalanine. Additionally, the use of a UV-C lamp accelerates oxidative enzymatic reactions.
Article
Chemistry, Inorganic & Nuclear
Cirlei Igreja Nascimento Mitre, Bruna Ferreira Gomes, Elaine Paris, Carlos Manuel Silva Lobo, Christina Roth, Luiz Alberto Colnago
Summary: The corrosion of metals is a significant issue that modern societies face. A study was conducted to evaluate the effect of a magnetic field on the corrosion of copper. It was found that the magnetic field reduced the corrosion rate by preventing the arrival of corrosive agents and contributing to the formation of a specific phase.
Article
Biochemistry & Molecular Biology
Henrique R. Teles, Leonardo L. G. Ferreira, Marilia Valli, Fernando Coelho, Adriano D. Andricopulo
Summary: In this study, 2D- and 4D-quantitative structure-activity relationship (QSAR) models were developed to investigate the activity of a series of oxazole and oxadiazole derivatives against Leishmania infantum, the causative agent of visceral leishmaniasis. A clustering strategy based on structural similarity was used to divide the compounds into two groups, followed by the development of 2D- (R-2 = 0.90, R(2)pred = 0.82) and 4D-QSAR models (R-2 = 0.80, R(2)pred = 0.64) with improved statistical robustness and predictive ability.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Biochemistry & Molecular Biology
G. de Oliveira Machado, Gustavo Galastri Teixeira, Rodrigo Henrique dos Santos Garcia, Tiago Bueno Moraes, Evandro Bona, Poliana M. Santos, Luiz Alberto Colnago
Summary: Low Field Time-Domain Nuclear Magnetic Resonance (TD-NMR) relaxometry was used to directly determine the moisture, fat, and defatted dry matter contents in commercial packaged requeijao cremoso (RC) processed cheese. By optimizing variable selection and using chemometric modeling, it was found that CWFP-T-1 data can be a fast method to monitor the quality of RC directly in commercial packages.
Article
Polymer Science
Robson Pereira, Kenia S. Freitas, Polyanna M. Pereira, Tiago Venancio, Samir L. Mathias, Aparecido J. de Menezes
Summary: The polysaccharide chitosan was modified with ethoxymethylenemalononitrile (ChMM) through a nucleophilic vinylic substitution reaction. The ChMM showed successful modifications as confirmed by spectroscopic and analytical techniques. The modified chitosan exhibited good dye removal capacity in both acidic and alkaline conditions.
POLYMER INTERNATIONAL
(2023)
Article
Biochemical Research Methods
Katia Celina Santos Correa, Ariele Cristina Moreira, Amr Galal Abd El-Raheem Ibrahim, Hugo Cesar Ramos de Jesus, Kelli Cristina Micocci, Flavio Vinicius Crizostomo Kock, Odair C. Bueno, Tiago Venancio, Flavio Henrique-Silva, Dulce Helena F. Souza
Summary: Cysteine peptidases play important roles in insect development and could be potential targets for insect control. In this study, a cysteine cathepsin L was characterized from the leaf-cutting ant, Atta sexdens. The protein, AsCathL, showed expression throughout insect development and in all body parts of the adult ant, indicating its function as a lysosomal cathepsin. Phylogenetic analysis revealed its similarity to other predicted cathepsins in ants. The enzyme exhibited hydrolytic activity at acidic pH and was inhibited by recombinant sugarcane cystatins. This study provides valuable insights into the cysteine peptidases of leaf-cutting ants and may contribute to future research on ant cathepsins.
PROTEIN EXPRESSION AND PURIFICATION
(2023)
Article
Materials Science, Multidisciplinary
Willian R. Caliman, Franciani C. Sentanin, Rodrigo C. Sabadini, Rodrigo H. S. Garcia, Tatiana Monaretto, Luiz A. Colnago, Agnieszka Pawlicka
Summary: This paper investigates nanocomposite polymer electrolytes (SPEs) consisting of montmorillonite (MMT; Na+SYN-1) and gellan gum. The characteristics of the membrane samples were analyzed using ATR-FTIR, TD-NMR, and SEM. The results showed an interaction between gellan gum and Na+SYN-1, as well as a more homogeneous surface in the nanocomposite with 40 wt.% Na+SYN-1. The application of NPEs in small electrochromic devices (ECDs) exhibited a decrease in peaks and charge density.
Article
Energy & Fuels
Ronny G. Huamani-Palomino, M. Pedro Ramos, Glenda Oliveira, Flavio Vinicius C. Kock, Tiago Venancio, Bryan M. Cordova
Summary: This paper investigates the extraction of pectin from cocoa pod husk using citric acid and characterizes its structure using NMR and FT-IR. The results show that the pectin from cocoa pod husk has a low degree of esterification, exhibits antioxidant activity, and is free from cadmium contamination.
BIOMASS CONVERSION AND BIOREFINERY
(2023)
Article
Infectious Diseases
Gabriela Marinho Righetto, Jose Luiz de Souza Lopes, Paulo Jose Martins Bispo, Camille Andre, Julia Medeiros Souza, Adriano Defini Andricopulo, Leila Maria Beltramini, Ilana Lopes Baratella da Cunha Camargo
Summary: Antimicrobial resistance is a major public health concern and there is a need for novel antimicrobial therapies. This study designed a new antimicrobial peptide Pln149-PEP20 and tested its activity against 60 different species of bacteria. The results showed that Pln149-PEP20 had excellent bactericidal activity and its target was likely genes associated with membrane metabolism.
Article
Plant Sciences
Leandro da Silva Oliveira, Camila M. M. Crnkovic, Marcelo R. R. de Amorim, Armando Navarro-Vazquez, Tiago A. A. Paz, Vitor F. F. Freire, Mirelle Takaki, Tiago Venancio, Antonio G. G. Ferreira, Renata de Freitas Saito, Roger Chammas, Roberto G. S. Berlinck
Summary: Metabolomics analyses and optimization of growth conditions were used to diversify phomactin terpenoids produced by the fungus Biatriospora sp. CBMAI 1333. Molecular networking results visualized on Gephi software facilitated the observation of phomactin diversification and guided the isolation and identification of a new nitrogen-bearing phomactin variant, phomactinine (1), with a rearranged carbon skeleton. The combination of metabolomics and chemometrics strategies can be expanded to integrate bioassay potency, structural novelty, and metabolic diversification, with or without genomic analyses.
JOURNAL OF NATURAL PRODUCTS
(2023)
Article
Chemistry, Analytical
Jessica Thais de Lima, Sonia Faria Zawadzki, Frederico Luis Felipe Soares, Kahlil Schwanka Salome, Andersson Barison, Tiago Bueno de Moraes, Caroline Da Ros Montes D'Oca
Summary: Counterfeiting of branded spirits is a growing global problem due to its potential economic gain and the difficulty for consumers to detect counterfeit spirits organoleptically. Apart from the health risks, counterfeit spirits impose financial liability on genuine suppliers and cause revenue loss for governments. The counterfeiting process involves refilling brand spirit bottles with cheaper alternatives or counterfeits and resealing them with authentic bottle caps, leaving behind traces that can be used for identification. Infrared Spectroscopy and Time-Domain Nuclear Magnetic Resonance are effective tools for detecting counterfeit spirits based on the analysis of bottle caps.
MICROCHEMICAL JOURNAL
(2023)
Article
Biochemistry & Molecular Biology
Daniel H. Lysak, Marco Grisi, Kathryn Marable, Gaurasundar M. Conley, Carl A. Michal, Vincent Moxley-Paquette, William W. Wolff, Katelyn Downey, Flavio V. C. Kock, Peter M. Costa, Kiera Ronda, Tiago B. Moraes, Katrina Steiner, Luiz A. Colnago, Andre J. Simpson
Summary: With the superior mass sensitivity offered by micro-coils, they are an excellent choice for studying tiny, mass limited samples such as eggs and small organisms. The recent development of CMOS-based micro-coil transceivers has shown great potential in achieving excellent mass sensitivity. This study explores the ability of broadband CMOS micro-coils to study heteronuclei in the context of environmental research, demonstrating promising results in terms of detection limits and successful analysis of environmentally relevant samples.
Article
Chemistry, Multidisciplinary
Nelson Adrian Villacres, Eder T. G. Cavalheiro, Carla C. Schmitt, Tiago Venancio, Hugo A. Alarcon, Ana C. Valderrama
Summary: This research aimed to extract sodium alginate from brown algae Macrocystis pyrifera and Lessonia trabeculata, and produce composite films composed of sodium alginate/ kappa-carrageenan/ iota-carrageenan, which were loaded with aminoethoxyvinylglycine. The extracted sodium alginate had low molecular weight and the composite films showed desirable drug release properties. Therefore, sodium alginate can be used to prepare composite films as an alternative to synthetic polymers for drug loading and release.
JOURNAL OF THE BRAZILIAN CHEMICAL SOCIETY
(2023)