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| Content Provider | World Health Organization (WHO)-Global Index Medicus |
|---|---|
| Author | Astefanei, Alina Schoenmakers, Peter J. Bäuerlein, Patrick Núñez, Oscar Kok, Wim Th de Voogt, Pim Galceran, Maria Teresa |
| Description | Author Affiliation: Astefanei A ( Analytical Chemistry Department, University of Barcelona, Martí i Franquès 1-11, E-08028 Barcelona, Spain. Electronic address: astefanei.alina@gmail.com.); Kok WT ( Analytical Chemistry Department-HIMS, University of Amsterdam, PO Box 94157, 1090 GD Amsterdam, The Netherlands.); Bäuerlein P ( KWR Watercycle Research Institute, Groningenhaven 7, PO Box 1072, 3430 BB Nieuwegein, The Netherlands.); Núñez O ( Analytical Chemistry Department, University of Barcelona, Martí i Franquès 1-11, E-08028 Barcelona, Spain); Galceran MT ( Analytical Chemistry Department, University of Barcelona, Martí i Franquès 1-11, E-08028 Barcelona, Spain.); de Voogt P ( IBED, University of Amsterdam, PO Box 94248, 1090 GE Amsterdam, The Netherlands.); Schoenmakers PJ ( Analytical Chemistry Department-HIMS, University of Amsterdam, PO Box 94157, 1090 GD Amsterdam, The Netherlands.) |
| Abstract | Fullerenes are carbon nanoparticles with widespread biomedical, commercial and industrial applications. Attributes such as their tendency to aggregate and aggregate size and shape impact their ability to be transported into and through the environment and living tissues. Knowledge of these properties is therefore valuable for their human and environmental risk assessment as well as to control their synthesis and manufacture. In this work, asymmetrical flow-field flow fractionation (AF4) coupled to multi-angle light scattering (MALS) was used for the first time to study the size distribution of surface modified fullerenes with both polyhydroxyl and carboxyl functional groups in aqueous solutions having different pH (6.5-11) and ionic strength values (0-200mM) of environmental relevance. Fractionation key parameters such as flow rates, flow programming, and membrane material were optimized for the selected fullerenes. The aggregation of the compounds studied appeared to be indifferent to changes in solution pH, but was affected by changes in the ionic strength. Polyhydroxy-fullerenes were found to be present mostly as 4nm aggregates in water without added salt, but showed more aggregation at high ionic strength, with an up to 10-fold increase in their mean hydrodynamic radii (200mM), due to a decrease in the electrostatic repulsion between the nanoparticles. Carboxy-fullerenes showed a much stronger aggregation degree in water (50-100nm). Their average size and recoveries decreased with the increase in the salt concentration. This behavior can be due to enhanced adsorption of the large particles to the membrane at high ionic strength, because of their higher hydrophobicity and much larger particle sizes compared to polyhydroxy-fullerenes. The method performance was evaluated by calculating the run-to-run precision of the retention time (hydrodynamic radii), and the obtained RSD values were lower than 1%. MALS measurements showed aggregate sizes that were in good agreement with the AF4 data. A comparison of the scattering radii from the MALS with the hydrodynamic radii obtained from the retention times in AF4 indicated that the aggregate shapes are far from spherical. TEM images of the fullerenes in the dry state also showed branched and irregular clusters. |
| ISSN | 00219673 |
| Volume Number | 1408 |
| e-ISSN | 18733778 |
| Journal | Journal of Chromatography A |
| Language | English |
| Publisher | Elsevier |
| Publisher Date | 2015-08-21 |
| Publisher Place | Netherlands |
| Access Restriction | One Nation One Subscription (ONOS) |
| Subject Keyword | Fullerenes Chemistry Fractionation, Field Flow Hydrogen-ion Concentration Light Nanoparticles Osmolar Concentration Particle Size Scattering, Radiation Solutions Water Journal Article Research Support, Non-u.s. Gov't Discipline Analytical Chemistry |
| Content Type | Text |
| Resource Type | Article |
| Subject | Organic Chemistry Medicine Analytical Chemistry Biochemistry |
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