Article
Chemistry, Organic
Trinadh Kaicharla, Bhavani Shankar Chinta, Thomas R. Hoye
Summary: This article provides examples that demonstrate the value of using properly designed and easily performed doping experiments to gain insights about the nature of analytes in a H-1 NMR sample. By conducting doping experiments on a complex mixture and a simple mixture, multiple compounds were successfully identified, highlighting the advantage of doping experiments over comparing spectra from separate samples containing the same analyte.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Aritro Sinha Roy, Madhur Srivastava
Summary: Analysis of small molecules is crucial in various fields, but current challenges hinder accurate identification of individual molecules in mixtures. This study presents a novel NMR spectroscopy method that enables reliable analysis of small molecule mixtures.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Biochemistry & Molecular Biology
Evangelos Dadiotis, Vangelis Mitsis, Eleni Melliou, Prokopios Magiatis
Summary: The widespread use of phytocannabinoids or cannabis extracts in various products, coupled with legal restrictions on THC content, has made it necessary to develop new, rapid, and universal analytical methods for quantifying them. In this study, an expanded H-1 qNMR method and a novel 2D-COSY qNMR method were developed for the rapid quantitation of ten major phytocannabinoids in cannabis plant extracts and products.
Article
Biochemistry & Molecular Biology
Samantha Klasfeld, Thomas Roule, Doris Wagner
Summary: Chromatin immunoprecipitation followed by sequencing (ChIP-seq) is a widely used method for identifying factor binding and chromatin modifications in genomic DNA. However, ChIP-seq data analysis is often affected by high artifactual signals. In this study, researchers developed an alternative approach called greenscreen for removing false-positive peaks in ChIP-seq data. Greenscreen is easy to implement and dramatically improves ChIP-seq peak calling and downstream analyses, making it a valuable tool for studying factor binding and occupancy changes.
Article
Plant Sciences
Amanda E. Martins, Montserrat Arista, Leonor Patricia Cerdeira Morellato, Maria Gabriela G. Camargo
Summary: Flower color is a primary attractant for pollinators and varies depending on the vegetation type and background, influencing the perception of flower color by pollinators like bees. Natural background colors affect bee discrimination of flower colors, highlighting the importance of considering environmental factors in analyzing flower color signals.
AMERICAN JOURNAL OF BOTANY
(2021)
Article
Construction & Building Technology
Yawen Tan, Huaxin Chen, Rui He
Summary: This paper investigates the curing effect and water transport characteristics of SAP in cement-based materials. When SAP is in contact with water or cement filtrate, exchangeable cations will quickly move to the solution and exchange with metal cations. The primary form of water in cement-based mixtures is absorbed water.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Chemistry, Applied
Rosa Maria Alonso-Salces, Luis Angel Berrueta, Beatriz Quintanilla-Casas, Stefania Vichi, Alba Tres, Maria Isabel Collado, Carlos Asensio-Regalado, Gabriela Elena Viacava, Aimara Ayelen Poliero, Enrico Valli, Alessandra Bendini, Tullia Gallina Toschi, Jose Manuel Martinez-Rivas, Wenceslao Moreda, Blanca Gallo
Summary: This study utilized H-1 NMR fingerprinting of edible oils and multivariate classification and regression models to accurately identify olive oils and their blends with other vegetable oils, providing support for regulations and control bodies. The models showed stable binary classification for olive oil type and precise determination of percentage of vegetable oil in the mixture. The approach demonstrated satisfactory performance with blind samples, confirming its potential for authenticity and traceability assurance.
Article
Spectroscopy
Li Wei, He Yao, Lin Dong-yue, Dong Rong-lu, Yang Liang-bao
Summary: In the analysis of trace substances in hair by SERS, the coupling of characteristic peaks of hair and background peaks of the substrate leads to identification errors and masking interference. Conventional peak deduction methods distort the surrounding peaks. This paper proposes a Gaussian mixture model that accurately establishes the SERS signal and ensures minimal distortion of adjacent peaks.
SPECTROSCOPY AND SPECTRAL ANALYSIS
(2023)
Article
Chemistry, Multidisciplinary
C. Penrose, P. Steiner, L. F. Gladden, A. J. Sederman, A. P. E. York, M. Bentley, M. D. Mantle
Summary: In this study, a quick and simple liquid H-1 NMR method using a benchtop H-1 NMR spectrometer was reported to determine the surface hydroxyl density of silica, with results showing excellent agreement with the literature.
CHEMICAL COMMUNICATIONS
(2021)
Article
Multidisciplinary Sciences
Stephanie Watermann, Marie-Christin Bode, Thomas Hackl
Summary: This paper presents a three-dimensional mathematical correlation method for the direct identification of metabolites from complex mixtures using NMR and MS data. The approach allows for semi-automatic detection of correlated NMR and MS data, facilitating the identification of known metabolites and unknown compounds in any complex mixture.
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Physical
Dovile. Lengvinaite, Sonata Kvedaraviciute, Stase Bielskute, Vytautas Klimavicius, Vytautas Balevicius, Francesca Mocci, Aatto Laaksonen, Kestutis Aidas
Summary: The H-1 NMR chemical shift of water in aqueous mixtures with [C4mim][Cl] IL shows a non-monotonic dependence, with a clear minimum observed at a molar fraction of IL of 0.34. The presence of strongly hydrogen-bonded complexes between chloride anions and water molecules is found to be the main reason behind the change in H-1 NMR chemical shift. Additionally, water molecules trapped in the IL matrix show considerably smaller chemical shifts compared to neat water.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Computer Science, Artificial Intelligence
Giulia Fischetti, Nicolas Schmid, Simon Bruderer, Guido Caldarelli, Alessandro Scarso, Andreas Henrici, Dirk Wilhelm
Summary: We propose a novel supervised deep learning approach for the automatic detection and classification of multiplets in H-1 NMR spectra. Our deep neural network is trained on synthetic spectra and shows effective detection of signal regions and minimized classification errors. The network also demonstrates good generalization on real experimental H-1 NMR spectra.
FRONTIERS IN ARTIFICIAL INTELLIGENCE
(2023)
Article
Pharmacology & Pharmacy
N. M. Mansour, D. T. El-Sherbiny, F. A. Ibrahim, H. I. El-Subbagh
Summary: Green spectrophotometric methods were developed and validated for the determination of CNS active drugs. The double divisor-ratio spectra derivative method was used to assay a ternary mixture of Piracetam, Levetiracetam, and Brivaracetam (method I), while the difference spectrophotometric method was applied to assay a binary co-formulated mixture of Piracetam and Vincamine (method II). The methods provided accurate results for the determination of the drugs without interference, and the use of AGREE assessment tool confirmed their environmental benignity.
ANNALES PHARMACEUTIQUES FRANCAISES
(2022)