We demonstrate a controllable surface-coordinated linear polymerization of long-chain poly(phenylacetylenyl)s that are self-organized into a "circuit-board" pattern on a Cu(100) surface. Scanning tunneling microscopy/spectroscopy (STM/S) corroborated by ab initio calculations, reveals the atomistic details of the molecular structure, and provides a clear signature of electronic and vibrational properties of the poly(phenylacetylene)s chains. Notably, the polymerization reaction is confined epitaxially to the copper lattice, despite a large strain along the polymerized chain that subsequently renders it metallic. Polymerization and depolymerization reactions can be controlled locally at the nanoscale by using a charged metal tip. This control demonstrates the possibility of precisely accessing and controlling conjugated chain-growth polymerization at low temperature. This finding may lead to the bottom-up design and realization of sophisticated architectures for molecular nano-devices.
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http://dx.doi.org/10.1038/srep02102 | DOI Listing |
Heliyon
January 2025
Environmental Health Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran.
In this study, a Cu@Ag core-shell was synthesized using a co-precipitation method. To create a new electrochemical sensor, a Cu@Ag core-shell with conductive polymers such as polyalizarin yellow R (PA) and Nafion (Nf) was immobilized on the surface of a glassy carbon electrode (Cu@Ag-Nf/PA/GCE). X-ray diffraction analysis (XRD), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FTIR) techniques were employed to characterize the Cu@Ag-Nf/PA/GCE.
View Article and Find Full Text PDFAnal Chim Acta
January 2025
College of Resources and Environment, Southwest University, Chongqing, 400716, China; Key Laboratory of Biomedical Analytics (Southwest University), Chongqing Science and Technology Bureau, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China. Electronic address:
Background: Because arsenate (As(V)) is a highly toxic pollutant, timely on-site monitoring of its concentration is crucial for mitigating potential environmental and health hazards. Traditional on-site detection methods for As(V) often face limitations of long response time and low sensitivity. Nanozymes are nanomaterials that exhibit enzyme-like catalytic activity.
View Article and Find Full Text PDFClin Chim Acta
January 2025
Department of Laboratories, Seattle Children's Hospital, Seattle, WA, United States; Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States. Electronic address:
Background: The complement membrane attack complex involves C5b-mediated assembly of C6-C9 polymers to form pores in cell membranes during complement activation. Inactive complexes can become soluble C5b-9 (sC5b-9) when they bind to Protein S. Elevated sC5b-9 levels are associated with increased risk of hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA), a serious condition which can be improved with eculizumab therapy.
View Article and Find Full Text PDFFood Chem
January 2025
Department of Chemistry, Faculty of Science, Marmara University, 34722 Istanbul, Turkey.
Within the scope of this study, a polymer-based optical sensor that can polymerize under UV radiation and produce fluorescence when suitable functional monomers and crosslinkers were prepared for aluminum determination in yogurt, soybean flour, and meat samples. Parameters such as operating range, pH, sensitivity, selectivity, determination limit, and foreign ion effect were thoroughly investigated to validate the developed method and characterize this polymer-based membrane. The designed sensor has wavelengths of 322 nm for fluorescence excitation and 356 nm for emission, respectively.
View Article and Find Full Text PDFJ Am Soc Mass Spectrom
January 2025
Laboratory of Chemistry and Technology of Polymers and Colors, Department of Chemistry, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
Biobased poly(ethylene furanoate) (PEF)/poly(ε-caprolactone) (PCL) block copolymers have been synthesized using ring opening polymerization (ROP) of ε-caprolactone (ε-CL) in the presence of PEF in different mass ratios. An increase in intrinsic viscosity is observed for the block copolymers with higher ε-CL content due to the extension of their macromolecular chain. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MS) was employed to understand the composition and structure of the produced block copolymers.
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