Determination of hydroquinone by flow injection chemiluminescence and using magnetic surface molecularly imprinted particles

We report on a flow injection chemiluminescence assay for hydroquinone (HQ) using Fe3O4 magnetic nanoparticles capped with oleic acid and coated with a polymer whose surface was molecularly imprinted for HQ to act as the recognition element. Dispersed in an oil phase, the surface imprinted particles display excellent adsorption capacity (63 mg∙g‾1) and a rapid adsorption rate. Packed into a flow cell, the addition of the reagents hexacyanoferrate(III), luminol and chlorhematin generates chemiluminescence whose intensity is linearly related to the concentration of HQ in the range from 2 × 10−7 to 1.0 × 10−5 mg∙mL‾1, with a detection limit of 7.9 × 10−8 mg∙mL‾1 and a relative standard deviation of 2.3 % at 1.0 × 10−7 mg∙mL‾1 HQ (n = 6). The method was successfully applied to the determination of HQ in spiked water samples.