A new formaldehyde sensor from silver nanoclusters modified Tollens' reagent

Kanokwan Chaiendoo; Sawarin Sooksin; Sirinan Kulchat; Vinich Promarak; Thawatchai Tuntulani; Wittaya Ngeontae

doi:10.1016/j.foodchem.2018.02.030

A new formaldehyde sensor from silver nanoclusters modified Tollens' reagent

Food Chem. 2018 Jul 30:255:41-48. doi: 10.1016/j.foodchem.2018.02.030. Epub 2018 Feb 7.

Authors

Kanokwan Chaiendoo¹, Sawarin Sooksin¹, Sirinan Kulchat¹, Vinich Promarak², Thawatchai Tuntulani³, Wittaya Ngeontae⁴

Affiliations

¹ Materials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand.
² School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wang Chan, Rayong 21210, Thailand.
³ Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
⁴ Materials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand. Electronic address: wittayange@kku.ac.th.

PMID: 29571494
DOI: 10.1016/j.foodchem.2018.02.030

Abstract

A selective colorimetric assay for detecting formaldehyde (FA) was proposed based on silver nanoclusters (AgNCs) templated by polymethacrylic acid (PMAA). The chemodosimeter was easily fabricated by the formation of Tollens' reagent in the presence of AgNCs (AgNCs@Tollens). The detection principle was based on the change in the color caused by the change in the particle size from nanoclusters (no LSPR) to nanoparticles (with LSPR) upon the reduction of Tollens' reagent by FA. In the presence of FA, the intensity of a new absorbance band with a maximum at a wavelength of 430 nm corresponding to the LSPR of the AgNPs linearly increased as a function of the FA concentration, exhibiting a color change that could be observed by the naked eye. This method provided a working range of 30-50 µM with lower detection limit (LOD) of 27.99 µM. The proposed method exhibited excellent selectivity towards FA over other aldehyde-containing compounds.

Keywords: Chemical sensors; Colorimetric sensors; Silver nanoclusters; Surface plasmon resonance; Tollens’ reagent.

MeSH terms

Colorimetry / methods
Formaldehyde / analysis*
Indicators and Reagents*
Limit of Detection
Metal Nanoparticles*
Particle Size
Polymethacrylic Acids
Silver*

Substances

Indicators and Reagents
Polymethacrylic Acids
Formaldehyde
polymethacrylic acid
Silver