Mixtures of l-Amino Acids as Reaction Medium for Formation of Iron Nanoparticles: The Order of Addition into a Ferrous Salt Solution Matters

International Journal of Molecular Sciences

Karolína M. Šišková³  Libor Machala²  Jiři Tuპk²  Josef Kašlík²  Peter Mojzeš¹ 

[1] Institute of Physics, Faculty of Mathematics and Physics, Charles University in Prague, Prague, Ke Karlovu 5, 121 16 Prague 2, Czech Republic; E-Mail:;Department of Experimental Physics, Regional Centre of Advanced Technologies and Materials, Palacký University in Olomouc, 783 71 Olomouc, Czech Republic; E-Mails:;Department of Physical Chemistry, Regional Centre of Advanced Technologies and Materials, Palacký University in Olomouc, 783 71 Olomouc, Czech Republic; E-Mail:

关键词: γ-Fe₂O₃;    FeOOH;    zero-valent iron;    NZVI;    Mössbauer spectroscopy;    SERS;    arginine;    arginate;    glutamic acid;    glutamate;    nanomagnetism;   

DOI  :  10.3390/ijms141019452

来源: mdpi

【 摘 要 】

Owing to Mössbauer spectroscopy, an advanced characterization technique for iron-containing materials, the present study reveals previously unknown possibilities using l-amino acids for the generation of magnetic particles. Based on our results, a simple choice of the order of l-amino acids addition into a reaction mixture containing ferrous ions leads to either superparamagnetic ferric oxide/oxyhydroxide particles, or magnetically strong Fe⁰-Fe₂O₃/FeOOH core-shell particles after chemical reduction. Conversely, when ferric salts are employed with the addition of selected l-amino acids, only Fe⁰-Fe₂O₃/FeOOH core-shell particles are observed, regardless of the addition order. We explain this phenomenon by a specific transient/intermediate complex formation between Fe²⁺ and l-glutamic acid. This type of complexation prevents ferrous ions from spontaneous oxidation in solutions with full air access. Moreover, due to surface-enhanced Raman scattering spectroscopy we show that the functional groups of l-amino acids are not destroyed during the borohydride-induced reduction. These functionalities can be further exploited for (i) attachment of l-amino acids to the as-prepared magnetic particles, and (ii) for targeted bio- and/or environmental applications where the surface chemistry needs to be tailored and directed toward biocompatible species.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland