title: Laser Desorption Ionization Quadrupole Ion Trap Time-of-Flight Mass Spectrometry of AumFen+/-Clusters Generated from Gold-Iron Nanoparticles and their Giant Nanoflowers. Electrochemical and/or Plasma Assisted Synthesis.
abstract: Gold nanoparticles (NP) with average diameter ~100 nm synthesized from tetrachloroauric acid solution using stainless steel as a reducing agent were found to contain iron. Applying simultaneously high frequency (HF) plasma discharge in solution during the electrochemical reduction, giant gold-iron nanoflowers with average size ~1000-5000 nm were formed. Scanning electron microscopy (SEM) shows the morphology of the nanopowders produced as polygonal yet nearly spherical, whereas iron content in both products determined by energy dispersive X-ray analysis (EDX) was found to be at ~2.5 at. %. Laser desorption ionization (LDI) of both nanomaterials and mass spectrometric analysis show the formation of AumFen+/-(m = 1-35; n = 1-3) clusters. Structure of few selected clusters in neutral or monocharged forms were computed by density functional theory (DFT) calculations and it was found that typical distances of an iron nucleus from adjacent gold nuclei lie in the interval 2.5 to 2.7 Å. Synthetized Au-Fe nanoparticles were found stable for at least 2 mo at room temperature (even in aqueous solution) without any stabilizing agent. Produced Au-Fe nanoparticles in combination with standard MALDI matrices enhance ionization of peptides and might find use in nanomedicine. Graphical Abstract ᅟ.
authors.affiliation: Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A14, 625 00, Brno, Czech Republic.
authors.forename: Ravi Madhukar
authors.initials: RM
authors.lastname: Mawale
authors.affiliation: Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A14, 625 00, Brno, Czech Republic.
authors.forename: Mayuri Vilas
authors.initials: MV
authors.lastname: Ausekar
authors.affiliation: Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic.|CEPLANT, R&D Center for Low-Cost Plasma and Nanotechnology Surface Modifications, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic.
authors.forename: David
authors.initials: D
authors.lastname: Pavliňák
authors.affiliation: Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic.|CEPLANT, R&D Center for Low-Cost Plasma and Nanotechnology Surface Modifications, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic.
authors.forename: Oleksandr
authors.initials: O
authors.lastname: Galmiz
authors.affiliation: Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A14, 625 00, Brno, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Kubáček
authors.affiliation: Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A14, 625 00, Brno, Czech Republic. havel@chemi.muni.cz.|International Clinical Research Center, St. Anne's University Hospital, Pekařská 53, 656 91, Brno, Czech Republic. havel@chemi.muni.cz.
authors.forename: Josef
authors.identifier: 0000-0002-6675-5671
authors.initials: J
authors.lastname: Havel
keywords: Laser desorption ionization; Mass spectrometry; Nanoflowers; Nanoparticles; Plasma-assisted; Stainless steel