Carbon dots as fluorescent sensor for detection of explosive nitrocompounds

• Type: Article in International Scientific Journal
• Date: 2016

Authors

Campos, BB (Author) Other; Contreras Caceres, R (Author) Other; Bandosz, TJ (Author) Other; Jimenez Jimenez, J (Author) Other; Rodriguez Castellon, E (Author) Other; Joaquim C G E Esteves da Silva (Author) FCUP; Algarra, M (Author) Other

Journal

Title: Carbon

Vol. 106

Pages: 171-178

ISSN: 0008-6223

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 103 Citations

Scopus - 112 Citations

Other information

Authenticus ID: P-00N-19B

DOI: 10.1016/j.carbon.2016.05.030

Abstract (EN): Highly and stable fluorescent carbon dots (CQDs), with lambda(ex)/lambda(em) = 350/465 nm were obtained using a strong acid oxidation of activated carbon in aqueous suspension. The nanoparticles had a mean size of 12 nm and quantum yield of 3.94%. After functionalization with amine groups by PAMAM-NH2 dendrimer (CQDs@PAMAM-NH2), the size of particles increased and aggregates of 65 nm were formed. Quantum yield also increased to 6.33%. CQDs were characterized by various analytical techniques including ATR-FTIR, Raman, XPS and fluorescence spectroscopies. The prepared CQDs@PAMAM-NH2 were used as fluorescent ratiometric nanosensor of 4-chloro-2,6-dinitroaniline, which is a constituent of explosives. As a result of interactions, the fluorescence at 465 nm was quenched. Moreover, a new band at 507 nm emerged and it is linked to a charge transfer and the formation of a Meisenheimer complex. A ratio of fluorescence intensities at 465 and 507 nm (I-465/I-507) is used for a ratiometric fluorescence sensing. A linear detection ranges from 1.0 x 10(-5) to 6.0 x 10(-4) M with a detection limit of 2 mu M and accuracy of 0.85% as standard relative deviation (RSD, n = 10). The detection accuracy in the presence of other nitrocompounds was 2.80% as RSD.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8