A colorimetric agarose gel for formaldehyde measurement based on nanotechnology involving Tollens reaction

Abstract

Gold nanoparticles (Au NPs) coupled with Tollens reagent were used for measuring formaldehyde. Au@Ag core-shell NPs were formed along with distinct color changes from pink to deep yellow. This colorimetric system was further immobilized into an agarose gel, which was used for monitoring of gaseous formaldehyde.

A colorimetric assay for measuring iodide using Au@Ag core–shell nanoparticles coupled with Cu2+

“…Agarose gel has been proved to be a feasible matrix to embed colloidal NPs, since it is transparent, porous and contains a large amount of water [28]. Therefore, the mixture of Au@Ag core-shell NPs-Cu 2+ was embedded into agarose gels and used for the detection of I -.…”

HCHO-reactive molecule with dual-emission-enhancement property for quantitatively detecting HCHO in near 100% water solution

“…Although there are many types of formaldehyde detection methods, including piezoelectric sensors [9], electrochemical biosensors [10], quartz crystal microbalance [11,12], Raman spectroscopy [13], gas chromatography [14,15], liquid chromatography [16,17], X-ray diffraction (XRD), transmission electron microscopy (TEM) [18] and biosensor methods [19][20][21]. Novel sensor technologies are needed to enable real time, in situ detection of formaldehyde in a compact and reusable manner [22,23]. Due to simplicity, high sensitivity, and instantaneous response [24], rapid progress has been made in the development of fluorescent probes for metal ions, biomolecules and anions.…”

Colorimetric Determination of the Activity of Starch-Debranching Enzyme via Modified Tollens’ Reaction

“…That is, one aldehyde sugar molecule can be oxidized into a carboxylic acid along with the formation of electrons that can reduce silver ions to form silver nanoparticles (AgNPs). The unique plasmonic property of AgNPs generated from the Tollens’ reaction has been applied to the sensitive detection of various analytes [14,15,16,17]. Here, we employed the characteristic surface plasmon resonance of AgNPs to quantify the concentration of debranching products from amylopectin and determine the activity of DBEs.…”