A New Nanocatalytic Spectrophotometric Assay for Cationic Surfactant Using Phosphomolybdic Acid‐Formic Acid‐Nanogold as Indicator Reaction

Abstract

In the pH 7.4 Na 2 HPO 4 -NaH 2 PO 4 buffer solution, the cationic surfactant (CS) interacted with nanogold particles (NG) to form NG aggregations (NGA) that resulted in its color changing from wine red to blue-violet. NG has a strong catalysis on the formic acid-phosphomolybdic acid (PMo) colored reaction, but that of the NGA catalysis is weak. With the increase of CS concentration, the NGA increased and the NG decreased, the catalysis decreased and the absorption value at 700 nm decreased linearly. The concentrations of 6.25-250 nmol/L tetradecyl dimethyl benzyl ammonium chloride (TDBAC), 0.625-250 nmol/L cetyltrimethyl ammonium bromide (CTMAB) and 12.5 -500 nmol•L -1 dodecyldimethylbenzyl ammonium chloride (DDBAC) had good linear responses to the decreased absorption value (ΔA 700 nm ), with molar absorption coefficients of 2.2×10 6 , 2.1×10 6 and 9×10 5 L•mol -1 •cm -1 respectively. This method was simple, highly sensitive and low-cost.

Shape-controllable synthesis of hydrophilic NaLuF4:Yb,Er nanocrystals by a surfactant-assistant two-phase system

“…SDS has a comparatively high HLB (up to 40) [ 25 ], which means that it is able to provide considerable anionic hydrophilic groups. DDBAC, the positively charged quaternary ammonium salt can make itself absorbed on the surface with negative charge [ 26 ]. PEG is a polymer comes from polyhydric alcohols with relatively large viscosity.…”

A SERS nanocatalytic reaction and its application to quantitative analysis of trace Hg(ii) with Vitoria blue B molecular probe

“…24 Compared to inorganic and enzyme catalysis amplication, nanocatalysts are easy to control, highly efficient, easy to alloy and have good stability, and have been used in nanoanalysis to improve analytical features, with spectrophotometric, uorescence and resonance Rayleigh scattering (RRS) detection techniques. [25][26][27][28][29][30] Although many SERS methods have been developed for qualitative analysis, there are no reports about the SERS active nanocatalytic particle reaction and labelfree VBB SERS methods for the quantitative analysis of trace Hg. In this article, a simple, sensitive and selective SERS active nanocatalytic indicator reaction of Hg 2+ -HAuCl 4 -NaH 2 PO 2 was studied, and used to determine trace mercury ions quantitatively, based on the nanomercury catalysis and the SERS effect of VBB on the surfaces of AuNP product in aqueous solution as nanosol substrate.…”

Autocatalytic Oxidization of Nanosilver and Its Application to Spectral Analysis

“…Among the nanocatalysis, the reports were mainly about nanogold catalysis and nano titanium dioxide photocatalysis 17 18 19 . Recently, some new nanocatalytic analytical methods were established 20 21 22 23 24 25 , based on the catalysis of nanogold on the Cu(II)-glucose, HAuCl 4 -ascrobic, HAuCl 4 -citrate, Te(IV)-Sn(II), phosphomolybdic acid-formic acid and Ag(I)-hydroquinone particle reactions. It is rare report about nanosilver catalytic reaction.…”

“…It is one of the important factors to affect the transfer, transformation, and ecological effect of chemical substances in water, and it is also one of the main reasons in the formation of acid rain 29 . In addition, the detection of H 2 O 2 content is also very important in biochemical reactions, clinical test, food safety, and other fields 20 21 22 23 24 25 26 27 28 29 30 31 32 . At present, the spectral methods for H 2 O 2 content are mainly including chemiluminescence, fluorescence, spectrophotometry, etc 33 34 35 .…”