Determination of Trace Formaldehyde Based on Formation of Silver Nanoparticles

In an alkaline solution,Ag+ can be reduced by formaldehyde to form silver nanoparticles,leading to the resonance light scattering(RLS) intensities of the system to be enhanced.Based on these phenomena,a new RLS method for trace formaldehyde determination in environment water samples was established.Under the optimized reaction conditions,the enhanced RLS intensities of the system has a good relationship with the concentration of formaldehyde in a range of 1.0×10-6～2.0×10-5 mol/L with the detection limit of 1.0×10-7 mol/L.The standard addition recovery ratio is in a range of 96.26% to 103.32% for formaldehyde detection in environmental water samples and in the indoor air.According to the phenomenon that the resultant from the reaction of Ag+ and formaldehyde has different colors in the presence of formaldehyde with different concentrations,a visual semi-quantificational method for detection of formaldehyde could be achieved.