Gold nanoclusters decorated hollow ZIF-8 encapsulating iron-catecholates as oxidase mimetics for ratiometric colorimetric detection of nitrite

Mikrochim Acta. 2024 Dec 21;192(1):23. doi: 10.1007/s00604-024-06879-z.

Abstract

Gold nanoclusters decorated hollow ZIF-8 encapsulating iron-catecholates (Fe-HHTP@HZIF-8@ AuNCs) was formed through self-assembly of Fe3+ and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP), in situ embedding of ZIF-8, and Au3+-Zn2+ exchange reaction. Its morphology and structure were fully characterized by high-resolution transmission electron microscopy, X-ray diffraction, transmission electron microscopy element mapping, and X-ray photoelectron spectroscopy. Additionally, its oxidase-like activity was explored with Km of 0.21 mM and Vmax of 1.74 × 10-6 M·s-1 toward 3,3',5,5'-tetramethylbenzidine (TMB). Due to its excellent catalytic activity and nitrite mediated diazotization of oxTMB, a ratiometric colorimetric method for nitrite detection was established and validated with wide linear range (2.0-400.0 μM), low LOD (0.12 μM), high accuracy (recovery of 95.11-102.14%), and good selectivity. This method was then utilized to determine the nitrite content in sausages and tap water. This study provided a new idea for developing efficient nanozymes and offered an accurate approach for nitrite determination.

Keywords: Diazotization reaction; Nanozymes; Nitrite; Oxidase-like activity; Photometric detection; Ratiometric colorimetric detection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzidines / chemistry
  • Biomimetic Materials / chemistry
  • Colorimetry* / methods
  • Gold* / chemistry
  • Imidazoles / chemistry
  • Iron / chemistry
  • Limit of Detection*
  • Metal Nanoparticles* / chemistry
  • Nitrites* / analysis
  • Oxidoreductases / chemistry

Substances

  • Nitrites
  • Gold
  • Iron
  • Oxidoreductases
  • Benzidines
  • Imidazoles
  • 3,3',5,5'-tetramethylbenzidine