Abstract
Graphitic carbon nitride quantum dots (gCNQDs) when alone or containing embedded 4-amino-2,2,6,6-tetramethyl(piperidin-1-yl)oxyl) (4-AT) (gCNQDs-4-AT(embedded)) were synthesized via low temperature in situ one-pot process from diaminomaleonitrile (DAMN). The blue emission of both gCNQDs and gCNQDs-4-AT were excitation wavelength–dependent with very high fluorescence quantum yields of 43 and 51%, respectively. Further, the gCNQDs were covalently linked to 4-AT via an amide bond to give (gCNQDs-4-AT (linked)). gCNQDs were also non-covalently linked to 2,2,6,6-etramethyl(piperidin-1-yl)oxyl (TEMPO, not containing amino groups) derivatized zinc phthalocyanine (ZnPc) to form gCNQDs-TEMPO-ZnPc(π-π). The TEMPO-derivatized gCNQDs (gCNQDs-4-AT(embedded)), gCNQDs-4-AT(linked), or gCNQDs-TEMPO-ZnPc(π-π) were found to be highly sensitive and selective fluorescent probes for ascorbic acid (AA) detection with limits of detection (LOD) in the nanomolar range. Hence, 4-AT (or TEMPO) functionality introduced into the gCNQDs (or ZnPc) afforded the derivation of selective and sensitive AA probes. Real samples were evaluated by the designed probes and satisfactory recoveries further confirmed the analytical applicability of the gCNQDs-based probes.
Original language | English |
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Pages (from-to) | 113-126 |
Number of pages | 14 |
Journal | Analytica Chimica Acta |
Volume | 991 |
DOIs | |
Publication status | Published - 18 Oct 2017 |
Bibliographical note
Funding Information:This work was supported by the Department of Science and Technology (DST) and National Research Foundation (NRF), South Africa through DST/NRF South African Research Chairs Initiative for Professor of Medicinal Chemistry and Nanotechnology (UID 62620) as well as Rhodes University/DST Centre for Nanotechnology Innovation, Rhodes University, South Africa.
Funding Information:
This work was supported by the Department of Science and Technology (DST) and National Research Foundation (NRF), South Africa through DST/NRF South African Research Chairs Initiative for Professor of Medicinal Chemistry and Nanotechnology (UID 62620) as well as Rhodes University / DST Centre for Nanotechnology Innovation, Rhodes University, South Africa . Appendix A
Publisher Copyright:
© 2017 Elsevier B.V.