title: Aggregation behavior of fullerenes in aqueous solutions: a capillary electrophoresis and asymmetric flow field-flow fractionation study.
abstract: In this work, the electrophoretic behavior of hydrophobic fullerenes [buckminsterfullerene (C60), C70, and N-methyl-fulleropyrrolidine (C60-pyrr)] and water-soluble fullerenes [fullerol (C60(OH)24); polyhydroxy small gap fullerene, hydrated (C120(OH)30); C60 pyrrolidine tris acid (C60-pyrr tris acid); and (1,2-methanofullerene C60)-61-carboxylic acid (C60CHCOOH)] in micellar electrokinetic capillary chromatography (MECC) was evaluated. The aggregation behavior of the water-soluble compounds in MECC at different buffer and sodium dodecyl sulfate (SDS) concentrations and pH values of the background electrolyte (BGE) was studied by monitoring the changes observed in the electrophoretic pattern of the peaks. Broad and distorted peaks that can be attributed to fullerene aggregation were obtained in MECC which became narrower and more symmetric by working at low buffer and SDS concentrations (below the critical micelle concentration, capillary zone electrophoresis (CZE) conditions). For the characterization of the suspected aggregates formed (size and shape), asymmetrical flow field-flow fractionation (AF4) and transmission electron microscopy (TEM) were used. The results showed that the increase in the buffer concentration promoted the aggregation of the particles, while the presence of SDS micelles revealed multiple peaks corresponding to particles of different aggregation degrees. Furthermore, MECC has been applied for the first time for the analysis of C60 in two different cosmetic products (i.e., anti-aging serum and facial mask).
authors: Department of Analytical Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain.
authors: Alina
authors: A
authors: Astefanei
authors: Department of Analytical Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain. oscar.nunez@ub.edu.|Serra Húnter Fellow, Generalitat de Catalunya, Barcelona, Spain. oscar.nunez@ub.edu.
authors: Oscar
authors: O
authors: Núñez
authors: Department of Analytical Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain.
authors: Maria Teresa
authors: MT
authors: Galceran
authors: Analytical Chemistry Group, HIMS, University of Amsterdam, PO Box 94157, 1090 GD, Amsterdam, The Netherlands.
authors: Wim Th
authors: WT
authors: Kok
authors: Analytical Chemistry Group, HIMS, University of Amsterdam, PO Box 94157, 1090 GD, Amsterdam, The Netherlands.
authors: Peter J
authors: PJ
authors: Schoenmakers
mesh_terms: D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods; D003358:Cosmetics / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods; D031521:Fractionation, Field Flow / Q000379:methods; D037741:Fullerenes / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008823:Micelles; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012995:Solubility; D014867:Water / Q000737:chemistry
chemical_list: D003358:Cosmetics; D037741:Fullerenes; D008823:Micelles; D014867:Water; D012967:Sodium Dodecyl Sulfate
keywords: Asymmetric flow field-flow fractionation; Capillary zone electrophoresis; Cosmetic products; Fullerene aggregates; Micellar electrokinetic capillary chromatography