Sensitive determination of trace mercury by UV-visible diffuse reflectance spectroscopy after complexation and membrane filtration-enrichment

► A simple, sensitive and selective solid phase reflectometry method is proposed for the determination of trace mercury in real water samples. ► The merits of the method include high enrichment efficiency, low cost, easy operation and no solvent elution or desorption. ► Hg-dithizone nanoparticles formed in solution can be enriched on the surface of the membrane. ► The method will be useful in monitoring the environment in view of mercury pollution.