Method for detecting nitrite based on silver-coated gold nanoparticles

The invention discloses a method for detecting nitrite based on silver-coated gold nanoparticles. The method comprises the following steps: adding a proper amount of HCl, AA and AgNO3 into gold nanoparticles to prepare the silver-coated gold nanoparticles; soaking a glass slide by adopting an MPTMS solution, a silver-coated gold nanoparticle solution and a naphthalene ethylenediamine hydrochloridesaturated solution in sequence; mixing a to-be-detected solution containing nitrite with a sulfanilic acid solution to form a mixed solution A; soaking the modified glass slide into the mixed solution A, cleaning the glass slide with ultrapure water after the reaction is finished, drying, and observing the light intensity change of the silver-coated gold nanoparticles through a dark field microscope to detect the content of nitrite. The method for detecting nitrite based on silver-coated gold nanoparticles has the advantages of convenience, rapidness, low detection lower limit, high sensitivity, high selectivity, spa