Green one-pot synthesis of nitrogen and sulfur co-doped carbon quantum dots as new fluorescent nanosensors for determination of salinomycin and maduramicin in food samples

Thiosemicarbazide functionalized carbon quantum dots as a fluorescent probe for the determination of some oxicams: application to dosage forms and biological fluids

“…In this method, a green and cost-effective fluorescent probe was produced adopting a hydrothermal technique using CA as a source of carbon to produce carboxyl coated CQDs. 47 The carboxylic groups of the prepared CQDs were then reacted with amine and sulfur groups of TSC to produce TSC functionalized CQDs ( Scheme 1 ). In their native condition, the synthesized N, S-CQDs are extremely water soluble, with no visible precipitation after 14 days at 4 °C.…”

Application of sulfur and nitrogen doped carbon quantum dots as sensitive fluorescent nanosensors for the determination of saxagliptin and gliclazide

“…Synthesis of S,N-CQDs was performed by applying a hydrothermal methodology that was recently reported by Magdy et al [ 26 ]. S,N-CQDs were prepared through mixing of 0.52 g CA and 0.68 g TS with 20 ml of double distilled water, and ultrasonication was carried out for 20 min.…”

“…Synthesis of doped CDs is usually carried out by inserting heteroatoms (such as nitrogen (N), phosphorus (P), sulfur (S), fluorine (F), boron (B)) into the CDs' general structure to enhance their photoluminescence properties [26,[34][35][36]. From literature, CDs were efficiently applied as sensitive probes for the determination of many pharmaceutical compounds in different matrices [26,37,38].…”

“…In the present study, a green, simple and economic method was adopted for preparation of S,N-CQDs applying a hydrothermal synthetic approach using thiosemicarbazide (TS) as nitrogen and sulfur source and citric acid (CA) as carbon source producing fluorescence probes for the estimation of each of GLZ and SXG [ 26 ].…”

A Label-Free Fluorescent Sensor Based on Si,N-Codoped Carbon Quantum Dots with Enhanced Sensitivity for the Determination of Cr(VI)

“…The carbon quantum dots first discovered by Xu during the purification and separation process of carbon nanotubes have the characteristics of broadband optical absorption, bright luminescence, good chemical and optical stability, high water solubility, simple preparation, and low preparation toxicity and good biocompatibility [ 14 , 15 ]. CQDs nanoparticles’ size, shape, and composition are determined by their precursors and synthesis pathways [ 16 ]. CQDs synthesis methods can be divided into two ways: (a) physical synthesis methods, such as arc discharge [ 17 ], laser ablation [ 18 ], and plasma induction [ 19 ]; (b) chemical synthesis methods, such as hydrothermal [ 20 ], electrochemical synthesis [ 21 ], solvothermal [ 22 ], microwave-assisted [ 23 ], and carrier-assisted [ 24 ].…”