A bicyclic peptide, cyclo (L-Glu(1)-D-Leu(2)-Aib(3)-L-Lys(4)-D-Leu(5)-D-Ala(6))-cyclo-(1gamma-4epsilon) (I), was designed and synthesized to provide an ammonium ion complexation site in a tetrahedral geometry. Molecular modeling, dynamics and electrostatic studies for I indicated that it exhibits some selectivity for ammonium ions over potassium and sodium ions. NMR measurements in CDCl(3)/CD(3)OD (1:1) show that for those carbonyl groups involved in cation binding, (13)C resonances shifted downfield with increasing cation concentration. The resonance that exhibited the largest change in chemical shift between uncomplexed and complexed forms was used to determine the selectivity. Selectivity values obtained were logK(NH(4) (+), Na(+) ) = - 2.4 and logK(NH(4) (+), K(+) ) = - 0.6.
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Adv Sci (Weinh)
January 2025
Research Center for Membrane and Film Technology, Department of Chemical Science and Engineering, Kobe University, Kobe, 6500034, Japan.
Membrane technology holds significant potential for the recovery of acids and alkalis from industrial wastewater systems, with ion exchange membranes (IEMs) playing a crucial role in these applications. However, conventional IEMs are limited to separating only monovalent cations or anions, presenting a significant challenge in achieving concomitant H⁺/OH⁻ permselectivity for simultaneous acid and alkali recovery. To address this issue, the charged microporous polymer framework membranes are developed, featuring rigid Tröger's Base network chains constructed through a facile sol-gel process.
View Article and Find Full Text PDFBiomater Sci
January 2025
Institute of Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany.
We are facing a shortage of new antibiotics to fight against increasingly resistant bacteria. As an alternative to conventional small molecule antibiotics, antimicrobial polymers (AMPs) have great potential. These polymers contain cationic and hydrophobic groups and disrupt bacterial cell membranes through a combination of electrostatic and hydrophobic interactions.
View Article and Find Full Text PDFJ Anal Toxicol
January 2025
ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, UT, USA.
Unlabelled: Background - Alcohol is the most abused substance in Western society, resulting in major economic losses and negative health consequences. Therefore, there is a need for a selective and robust detection method for alcohol consumption in various clinical and forensic settings. This study aimed to validate a mass spectrometry method for quantifying phosphatidylethanol (PEth) and perform retrospective data analysis from the patient population of a national reference laboratory.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Department of Microbiology, College of Life Science, Key Laboratory for Agriculture Microbiology, Shandong Agricultural University, Tai'an 271018, PR China; School of Pharmacy, the Key Laboratory of Medical Antibacterial Materials of Shandong Province, Binzhou Medical University, Yantai 264003, PR China. Electronic address:
Chronic wounds caused by microbial infection have emerged as a major challenge on patients and medical health system. Bacterial cellulose (BC) characterized by its excellent biocompatibility and porous network, holds promise for addressing complex wound issues. However, lack of inherent antibacterial activity and cross-linking sites in the molecular network of BC have constrained its efficacy in hydrogel design and treatment of bacterial-infected wounds.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
School of Chemistry and Chemical Engineering, Tianjin University of Technology, 391 Binshuixidao, Tianjin 300384, China.
Catheter-associated urinary tract infection (CAUTI) induced by rapid bacterial colonization and biofilm formation on urinary catheters is a key issue that urgently needs to be addressed. To prevent CAUTI, many contact-killing, non-leaching coatings have been developed for the surfaces of silicone catheters. However, due to the chemical inertness of the silicone substrate, most current coatings lack adhesion and are unstable under external forces.
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