We report a size-controllable synthesis of stable aqueous solutions of ultrapure low-size-dispersed Au nanoparticles by methods of femtosecond laser fragmentation from preliminary formed colloids. Such approach makes possible the tuning of mean nanoparticle size between a few nm and several tens of nm under the size dispersion lower than 70% by varying the fluence of pumping radiation during the fragmentation procedure. The efficient size control is explained by 3D geometry of laser fragmentation by femtosecond laser-induced white light super-continuum and plasma-related phenomena. Despite the absence of any protective ligands, the nanoparticle solutions demonstrate exceptional stability due to electric repulsion effect associated with strong negative charging of formed nanoparticles. Stable aqueous solutions of bare gold nanoparticles present a unique object with a variety of potential applications in catalysis, surface-enhanced Raman spectroscopy, photovoltaics, biosensing and biomedicine.
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http://dx.doi.org/10.1088/0957-4484/26/6/065601 | DOI Listing |
Investig Clin Urol
January 2025
Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
The global increase in urolithiasis prevalence has led to a shift towards minimally invasive procedures, such as retrograde intrarenal surgery, supported by advancements in laser technologies for lithotripsy. Pulsed lasers, particularly the holmium YAG and the newer thulium fiber laser, have significantly transformed the management of upper urinary tract stones. However, the use of high-power lasers in these procedures introduces risks of heat-related injury.
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.
View Article and Find Full Text PDFF S Rep
December 2024
Reproductive Center, Medical Corporation Group Mio Fertility Clinic, Kuzumo-Minami, Yonago, Japan.
Objective: To investigate whether artificial removal of zona pellucida (ZP) at the pronuclear stage improves good-quality embryos and blastocyst development in patients with difficulty conceiving because of severe fragmentation in early-cleavage stage.
Design: Exploratory investigation.
Setting: Reproductive center.
Arab J Urol
September 2024
Department of Urology, Kasr Alainy Hospitals, Faculty of Medicine, Cairo University, Cairo, Egypt.
Objectives: We aimed to assess the stone free rate of flexible ureteroscopy and laser lithotripsy (FURL) in upper urinary tract stones (UUTS) >20 mm and the risk of complications from ureteral access sheath (UAS) usage.
Methods: This is a prospective randomized clinical trial that included patients with UUTS larger than 20 mm who underwent FURL after randomization into two groups: group A (UAS) and group B (non-UAS). Data were collected for patients' demographics, stone parameters, operative and postoperative complications, and the outcome of FURL regarding stone-free rate (SFR) and perioperative complications, with a 6-month follow-up.
Anal Chem
January 2025
Department of Chemistry, Indiana University, 800 Kirkwood Avenue, Bloomington, Indiana 47401, United States.
Charge detection mass spectrometry (CD-MS) is used to monitor the dissociation of large (300 kDa to 20 MDa) protein complexes in droplets heated with a 10.6 μm CO laser. In this approach, electrospray ionization (ESI) is used to produce charged droplets containing macromolecular complexes.
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