The removal behavior of self-assembled monolayers (SAMs) of thiol molecules on a gold substrate by an NH(4)OH-H(2)O(2)-H(2)O solution was studied using attenuated total reflectance infrared spectroscopy (ATR-IR) and atomic force microscopy (AFM). Furthermore, the impact of the concentration of NH(4)OH and H(2)O(2) in the solution and reaction temperature on the SAM removal rate and efficiency was explored. The SAM removal rate and efficiency were significantly influenced by the concentration of NH(4)OH rather than H(2)O(2). The solution containing the 2 : 1 molar ratio of NH(4)OH : H(2)O(2) among three different solutions showed the highest removal rate and efficiency in the removal of 11-mercapto-1-undecanol. The increase in the reaction temperature resulted in the enhancement on the SAM removal rate, but it led to the fast delamination of the gold layer. These results may be useful in the regeneration of sensor surfaces relying on gold/thiol chemistry.
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http://dx.doi.org/10.1002/sca.20089 | DOI Listing |
J Am Coll Cardiol
December 2024
Icahn School of Medicine at Mount Sinai, New York, New York, USA.
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Vaccines (Basel)
December 2024
National Institutes for Food and Drug Control, No. 31, Huatuo Road, Beijing 102629, China.
Background: The Vero cell rabies vaccine is currently the most widely used human rabies vaccine. However, owing to the presence of residual host cell DNA (HCD) in the final product and the potential tumorigenicity of the DNA of high-passage Vero cells, the WHO not only sets a limit on the number of times cells used in production can be passaged, but also imposes strict requirements on the amount of residual HCD in the final vaccine product.
Objectives: To systematically reduce the HCD level in the final vaccine product, multiple purification steps are included in the vaccine production process.
Sensors (Basel)
December 2024
IDEKO Research Center, Basque Research and Technology Alliance (BRTA), 20870 Elgoibar, Spain.
Traditional marker-based photogrammetry systems often require the attachment and removal of a sticker for each measured point, involving labor-intensive manual steps. This paper presents an innovative approach that utilizes raised, cross-shaped markers, referred to as 'molded markers', directly embedded into composite pieces. In this study, these markers, commonly employed in other industrial processes, serve as fiducial markers for accurate photogrammetry.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Department of Chemistry, University of Hannam, Daejeon 34430, Republic of Korea.
The chemical mechanical polishing/planarization (CMP) is essential for achieving the desired surface quality and planarity required for subsequent layers and processing steps. However, the aggregation of slurry particles caused by abrasive materials can lead to scratches, defects, increased surface roughness, degradation the quality and durability of the finished surface after milling processes during the CMP process. In this study, ceria slurry was prepared using polymer dispersant with zinc salt of ethylene acrylic acid (EAA) copolymer at different contents of 5, 6, and 7 wt% (denoted as D5, D6, and D7) to minimize particle aggregation commonly observed in CMP slurries.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Polymer Science Program, Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat-Yai 90110, Thailand.
Water pollution is a major global issue, and antibiotic drugs released into aquatic environments by the pharmaceutical industry, such as ciprofloxacin, have negative consequences on both human health and the ecosystem. In this study, the performance of PVA as a polymer ligand for ciprofloxacin (CPFX) removal is evaluated through polymer-enhanced ultrafiltration using a novel composite PVC-ZnO membrane. The initial concentration of the ciprofloxacin solution, pH, ionic strength, ideal polymer concentration, duration, and maximum retention capacity were among the factors that were examined.
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