Copper (I) and (II) complexes of melamine

Wiles, Austin; Bozzuto, Daniel; Cahill, Christopher L.; Pike, Robert D.

doi:10.1016/j.poly.2005.08.022

Cited by 44 publications

(35 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, changes in the N−H stretching and ring distortion absorption region suggested that coordination occurred through the amine nitrogen atoms together with those of triazine in melamine. 31 Quenching Mechanism. The restored sp 2 -bonded carbon network of GQDs could serve as a substrate for anchoring aromatic molecules through π−π stacking.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…On the other hand, it is expected that GQDs may have a certain affinity for melamine due to their π-conjugated structures, and melamine can coordinate with metal ions (such as Cu 2+ and Ag + ). 31 In this way, melamine may act as a linkage agent between GQDs and metal ions to bring them into proximity of each other, leading to the FL quenching of GQDs. We therefore hypothesized that it might be possible to use GQDs as a fluorescent probe for selective determination of melamine.…”

Section: ■ Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Graphene Quantum Dots as Fluorescence Probes for Turn-off Sensing of Melamine in the Presence of Hg²⁺

Tao

et al. 2014

ACS Appl. Mater. Interfaces

124

View full text Add to dashboard Cite

A rapid and sensitive fluorescence sensing system for melamine based on charge transfer quenching of the fluorescence of graphene quantum dots (GQDs) in the presence of Hg(2+) is proposed. The synthesized GQDs were strongly luminescent with predominantly aromatic sp(2) domains. Melamine could coordinate with mercury through nitrogen atoms in both its amine and triazine groups and bring more Hg(2+) to the surface of GQDs through π-π stacking, thus leading to quenching of the GQDs' fluorescence. The quenching mechanism was investigated in detail and ascribed to charge transfer from the GQDs to Hg(2+) with melamine acting as the linkage agent. The melamine demonstrated a linear range 0.15-20 μM and a detection limit of 0.12 μM, which was far below the regulatory level, suggesting the promising practical usage of this sensing system. This sensing system also possessed high selectivity for melamine in the presence of possible interferences. Finally, this novel sensor was successfully applied for melamine detection in raw milk and satisfactory recovery was achieved.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

Graphene Quantum Dots as Fluorescence Probes for Turn-off Sensing of Melamine in the Presence of Hg²⁺

Tao

et al. 2014

ACS Appl. Mater. Interfaces

124

View full text Add to dashboard Cite

show abstract

“…The XRD pattern of the complex (data not shown) was clearly different from those of CuCl 2 and melamine. The infrared spectrum of the complex revealed characteristic peaks of melamine (data not shown), including N-H stretching modes between 2800-3500 cm À1 representing free and hydrogenbonded N-H (Wiles et al 2006). The method of continuous variation (Job's method) was employed to reveal complex stoichiometry in methanol.…”

Section: Copper(ii)-melamine Complex Characterizationmentioning

confidence: 99%

“…Melamine has affinity for copper ions (Colombo et al 1985;Wiles et al 2006;Chen, Yeh, and Chen 2006;L. F. Xu et al 2008;Zhu et al 2010), and consequently melamine may be determined by monitoring copper(II) by FAAS.…”

Section: Introductionmentioning

confidence: 99%

Determination of Melamine Based on the Formation of an Insoluble Copper-Melamine Complex and Flame Atomic Absorption Spectrometry

2014

View full text Add to dashboard Cite

A copper-melamine complex was optimally synthesized by heating excess copper(II), as 50 m mol L À1 copper(II) chloride in 50% (v=v) methanol, and melamine at 80 C. The amount of residual copper(II) in solution after removal of the copper-melamine complex was then measured by flame atomic absorption spectrometry. The concentration of depleted copper was proportional to the concentration of melamine, with a linear calibration curve (melamine concentration against copper absorbance) between 0.5 and 2.5 m mol L À1 (R 2 ¼ 0.9943) and with a limit of detection of 0.50 m mol L À1 . Although external standard calibration provided poor recoveries in fortified fish flesh (40% to 74% for 5 to 10 mg melamine/g), the method of standard addition provided acceptable values (90% to 93%), with a relative standard deviation of 3% to 10%. The results obtained with the standard addition method were in broad agreement with those obtained by high performance liquid chromatography.

show abstract

“…Therefore, there is an urgent need to develop simple, rapid, low-cost, highly sensitive and selective methods for melamine detection. For example, a simple colorimetric approach for the monitoring of melamine was recently reported based on the mechanism that the coordination capability of melamine to Hg 2+ was stronger than that to gold nanoparticles because of the formation of the multi-nitrogen heterocyclic ring special structures between melamine and Hg 2+ [28,29].…”

Section: Introductionmentioning

confidence: 99%

A dual functional electrochemical “on–off” switch sensor for the detection of mercury(II) and melamine

Jiang

Lan

et al. 2015

Sensors and Actuators B: Chemical

View full text Add to dashboard Cite

Copper (I) and (II) complexes of melamine

Cited by 44 publications

References 22 publications

Graphene Quantum Dots as Fluorescence Probes for Turn-off Sensing of Melamine in the Presence of Hg²⁺

Graphene Quantum Dots as Fluorescence Probes for Turn-off Sensing of Melamine in the Presence of Hg²⁺

Determination of Melamine Based on the Formation of an Insoluble Copper-Melamine Complex and Flame Atomic Absorption Spectrometry

A dual functional electrochemical “on–off” switch sensor for the detection of mercury(II) and melamine

Contact Info

Product

Resources

About

Copper (I) and (II) complexes of melamine

Cited by 44 publications

References 22 publications

Graphene Quantum Dots as Fluorescence Probes for Turn-off Sensing of Melamine in the Presence of Hg2+

Graphene Quantum Dots as Fluorescence Probes for Turn-off Sensing of Melamine in the Presence of Hg2+

Determination of Melamine Based on the Formation of an Insoluble Copper-Melamine Complex and Flame Atomic Absorption Spectrometry

A dual functional electrochemical “on–off” switch sensor for the detection of mercury(II) and melamine

Contact Info

Product

Resources

About

Graphene Quantum Dots as Fluorescence Probes for Turn-off Sensing of Melamine in the Presence of Hg²⁺

Graphene Quantum Dots as Fluorescence Probes for Turn-off Sensing of Melamine in the Presence of Hg²⁺