Morphological tuning of EuOS nanoparticles, manifestation of peroxidase-like activity and glucose assay use

• Published in: New journal of chemistry 2016-02, Vol.4 (2), p.1595-164
• Main Authors: Ghosh, Abhisek Brata, Saha, Namrata, Sarkar, Arpita, Dutta, Amit Kumar, Biswas, Papu, Nag, Kamalaksha, Adhikary, Bibhutosh
• Format: Article
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c5nj02705e

Eu 2 O 2 S nanoparticles have been synthesized by solvothermal decomposition of the precursor complex [NHEt 3 ] + [Eu(acda) 4 ] − , wherein acda − is the anion of 2-aminocyclopentene-1-dithiocarboxylic acid. Oleylamine alone or in combination with surface active agents, such as trioctylphosphine or oleic acid, at 280 °C produced nanoparticles of three different morphologies, namely, ultrathin nanoplates, nanospheres and short rods. The optical band energy of the nanoparticles has been found to be 4.57(8) eV. Eu 2 O 2 S particles exhibit strong photoluminescence at room temperature with a quantum yield of about 4% upon excitation at 285 nm. All three forms display peroxidase-like activity towards the oxidation of 3,3′,5,5′-tetramethylbenzidine in the presence of H 2 O 2 and follow a Michaelis-Menten enzymatic pathway. The mechanistic investigation reveals that the Eu 3+ /Eu 2+ redox couple plays a crucial role behind this catalytic process. Catalytic efficiency of the nanoparticles decreases in the order plates > spheres > rod-like particles. Based on peroxidase activity, selective detection and estimation of glucose in the presence of related carbohydrates has been carried out. We present a single source precursor driven synthesis of Eu 2 O 2 S with variable shapes, which effectively mimic peroxidase activity, and were successfully employed to selectively detect and determine glucose.