In this paper, the effect of alkyl substitution at the hydrogen bond acceptor and its chain length on the strength and nature of hydrogen bonding is presented. In the present study we combine both experimental and computational methods to investigate the characteristics of O-H...O and O-H...S hydrogen bonding in the complexes of p-cresol (p-CR) with methanol (MeOH), ethanol (EtOH), methanethiol (MeSH), and ethanethiol (EtSH). The results indicate that, with an increase in the alkyl chain length, both O-H...O hydrogen bonding and O-H...S hydrogen bonding become stronger. Energy decomposition analysis emphasizes the dispersive nature of O-H...S hydrogen bonding. In addition, it revealed that the dispersion energy contribution in O-H...O hydrogen bonding increases with an increase in the alkyl chain length of the hydrogen bond acceptor. In the case of O-H...S hydrogen bonding, however, the dispersion energy contribution decreased from 68% for the H(2)S complex to 53% in the case of the MeSH complex; it remained unchanged with a further increase of the alkyl chain length. It was also observed that the red shifts in the OH stretching frequency did not correlate with the proton affinities of the O-centered acceptor vs the S-centered H-bond acceptor, in contrast with the known trend for the conventional H-bonded complexes. The IR/UV double resonance study enabled the assignments of the anti and gauche conformers of p-CR-EtOH and p-CR-EtSH.
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Int J Biol Macromol
January 2025
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing 210037, China. Electronic address:
TEMPO-CNF film modified by two-dimension transition metal MXene has certain antibacterial properties. However, the problem of long-lasting stability greatly restricts the feasibility of long-term use of the composite film. Here, we introduced polyaniline (PANI) as a modifying molecule, which was electrostatically adsorbed on the surface of the MXene nanosheets to prevent its self-stacking and delay its oxidation.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Zhejiang Provincial Engineering Research Center for Green and Low-carbon Dyeing & Finishing, Zhejiang Sci-Tech University, Hangzhou 310018, China; Zhejiang Provincial Innovation Center of Advanced Textile Technology, Shaoxing 312000, China. Electronic address:
Comparing to the solvent-based and waterborne polyurethanes (PU), the solvent-free reactive PU (RPU) is prepared via in-situ polymerization and film-formation of isocyanate-capped prepolymers and macromolecular polyols in solvent-free system. Thus, the carbon emissions and environmental pollutions are significantly reduced. However, the rapid polymerization also challenges the well control of structure and properties, especially the ordered microstructures.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
School of Food Science and Engineering, Ningxia University, Yinchuan, Ningxia 750021, China. Electronic address:
The ternary complex effectively prevents droplet aggregation, Ostwald ripening, and phase separation through its gel network, thereby demonstrating its capability in bioactive compound delivery. In this work, the influence of varying chickpea protein isolate (CPI) levels on the microstructure, gel characteristics, stability and functional properties of grape seed proanthocyanidin (GSP) and konjac gum (KGM) stabilized ternary complexes was investigated. Visual appearance indicated the formation of a non-stratified ternary complex as the CPI enhanced to 3-4 %.
View Article and Find Full Text PDFComput Biol Chem
January 2025
Department of Biostatistics and Bioinformatics, ICMR-National Institute for Research in Environmental Health, Bhopal, Madhya Pradesh, India. Electronic address:
Plastics play an essential role in modern fisheries and their degradation releases micro- and nano-sized plastic particles which further causes ecological and human health hazards through various environmental contamination pathways and toxicity mechanisms, which can cause respiratory problems, cancer, reproductive toxicity, endocrine disruption and neurological effects in humans. This study utilized various bioinformatics tools through multi-step computational analyses to investigate the interactions between prevalent fisheries microplastics and the key protein receptor acetylcholinesterase (AChE), which is associated with neurotoxicity, as it can interfere with nerve impulses and muscle control. Our results indicate that the binding of seven polymers within AChE's active site, with dodecane and polypropylene exhibited highest affinity with hydrogen bonding were observed through Molecular docking of different program (PyRx) and servers (CB-Dock, eDock) then the stability of AChE-dodecane and AChE-polypropylene complexes were observed through MD simulations for 100 ns.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
State Key Laboratory of Advanced Drug Delivery and Release Systems, and Medical Science and Technology Innovation Center, School of Pharmaceutical Sciences & Institute of Materia Medica, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong 250117, China. Electronic address:
Considering the widespreadly use, large consumption, and serious environmental and health threats of phenylpyrazole insecticides (PPIs), development of a selective and sensitive method for accurate detection of their residuals in food samples is of great significance and challenging. Herein, depending on the hydrophobic and F-containing characteristics of PPIs, a novel fluorinated magnetic microporous organic network (FMMON) was designed and prepared for efficient and selective magnetic solid-phase extraction (MSPE) of two typical PPIs (fipronil and ethiprole) from milk and egg samples before the HPLC-UV determination. FMMON owned large specific surface area, multiple interaction sites, excellent magnetic separation performance and stability and exhibited good extraction and selectivity for fipronil and ethiprole through the specific F-F, hydrogen bonding, hydrophobic, and π-π interactions.
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