A novel fluorescent molecule based on 1,2,3-triazole for determination of palladium (II) and hydrazine hydrate in aqueous system

In recent years, hydrazine hydrate has been widely used in various fields as fuel and chemical raw materials, etc. However, hydrazine hydrate is also a potential threat to living body and natural environment. The effective method is urgently needed to detect hydrazine hydrate in our living environment. Secondly, as a precious metal, palladium has attracted more and more attention because of its excellent properties in industrial manufacturing and chemical catalysis. However, its potential danger is also slowly approaching, so it is necessary to find an excellent way to detect palladium, too. Herein, a fluorescent molecule, 4,4',4'',4'''-(1,4-phenylenebis(2H-1,2,3-triazole-2,4,5-triyl)) tetrabenzoic acid (NAT), was synthesized. Firstly, NAT has very high selectivity and sensitivity for determination of Pd²⁺, because Pd²⁺ can coordinate well with carboxyl oxygen of NAT. The detection performance of Pd²⁺ is that the linear range is from 0.06 to 4.50 μM and the detection limit is 16.4 nM. Furthermore, the chelate (NAT-Pd²⁺) can continue to be used for quantitative determination of hydrazine hydrate with a linear range of 0.05-6.00 μM and the detection limit is 19.1 nM. The interaction time of NAT-Pd²⁺ and hydrazine hydrate is about 10 min. Of course, it also has good selectivity and strong anti-interference ability for many common metal ions, anions and amine like compounds. At last, the ability of NAT to quantitatively detect Pd²⁺ and hydrazine hydrate in actual samples has also been verified and the results are very satisfactory.

Colorimetric sensing of palladium ions based on in situ generation of palladium nanoparticles as an activator for the thionine-hydrazine reaction

In this article, a simple and rapid colorimetric sensing method was developed for the determination of palladium ions. The method is based on in situ generation of palladium nanoparticles (PdNPs) upon reduction by hydrazine which then acts as an activator on the reduction reaction of thionine by hydrazine. The formation of PdNPs was characterized by UV-Vis spectrophotometry, particle size analysis and TEM images. The reaction was followed by measuring the thionine absorbance at 599 nm with time. Several factors influencing analytical performance of the kinetic method such as concentration of reactants and electrolyte, pH of the sample solution and temperature were investigated to achieve the optimum conditions and highest sensitivity. This method showed a linear calibration curve in the concentration range of 8-1200 ng mL^-1 for palladium ions. The limit of detection (LOD) was 6.5 ng mL^-1 and the relative standard deviations were 3.8% and 1.3% (n = 8) for two palladium ion concentrations of 60 and 300 ng mL^-1, respectively. The method was successfully applied to the determination of palladium in river water, pond water, wastewater and soil samples.

Pd2+fluorescent sensors based on amino and imino derivatives of rhodamine and improvement of water solubility by the formation of inclusion complexes with β-cyclodextrin

Mono- and bis-rhodamine derivatives appended with amino (RhB1) and imino (BRI) groups, respectively, have been designed as fluorescent sensors for Pd²⁺ions.

An efficient non-reaction based colorimetric and fluorescent probe for the highly selective discrimination of Pd0 and Pd2+ in aqueous media

A novel anthraquinone-imidazole based colorimetric and fluorogenic probe 1 discriminates the oxidation states of Pd⁰ and Pd²⁺ by naked eye with high selectivity in aqueous media due to the difference in coordination in the pocket of probe molecule.