English abstract
In this project, different types of carbon-based quantum dots (C-based QDs) were
synthesized by simple and green routes using safe precursors. They were utilized to obtain
highly sensitive and powerful multi-emission chemiluminescence (CL) systems. Several
attempts have been made to reach this goal through the development of three systems:
bis(2, 4, 6-trichlorophenyl) oxalate (TCPO)-hydrogen peroxide (H₂O₂) CL system, sulfite
(𝑆𝑂3
2−)-acidic permanganate (KMnO4) CL system and polyphosphate (PP)- acidic
KMnO4 CL system, each in the presence of a certain type of C-based QDs. These CL
reactions were carried out on a small square shaped chromatography paper substrate,
prepared by a paper cutting fabrication technique and 3D-printing, ending with the
development of a paper-based analytical device coupled with CL detection technique
(PAD-CL). Out of the three CL systems, two showed multi-emission peaks with well separated wavelengths. Careful optimization of the instrumental setup and various
experimental conditions were exploited in order to obtain the strongest emission and
highest sensitivity. Several experimental parameters were thoroughly optimized,
including the size of detection paper, the order of injecting the analyte and CL reagents,
the concentrations and volumes of various reagents and C-based QDs. The CL behavior
of C-based QDs were investigated and the CL mechanism of each developed system was
studied to clarify the role of QDs in the development and enhancement of the multi emission CL systems.
The analytical application of the developed systems is an important part to complete the
picture of the work. In this regards, the established CL systems were tested for different
analytical applications. Under optimal experimental conditions, good linear relationships
were observed between the studied analyte concentration and the CL intensity of the
established CL system.
The designed assays are characterized by their low-cost, ease of use, facile but accurate,
and high selectivity for the detection of different analytes in various spiked food and
environmental samples. Besides, the portability of these probes makes them suitable for
on-site screening purposes.
