A miniaturized electrochemical system for high sensitive determination of chromium(VI) by screen-printed carbon electrode with gold nanoparticles modification

Chromium(VI) has been known as a toxic heavy metal ion that can cause adverse effects to human health, including carcinogenic effects. An approach that can detect chromium(VI) in a rapid, sensitive and portable manner is of great importance. This paper presents a miniaturized portable electrochemical system for chromium(VI) determination based on a screen-printed carbon electrode with gold nanoparticles modification. The miniaturized electrochemical system is composed of an analyzer, a detection module integrated with a screen-printed carbon electrode and a laptop or smartphone. Gold nanoparticles were modified on the working electrode in screen-printed carbon electrode to implement high sensitive detection of chromium(VI). The effect of pH, different supporting electrolyte and scan rate were studied. With the optimized conditions, the calibration curve for chromium(VI) shows a sensitivity of 1.1 nA(μg/L)−1 and a linearity of 0.999 from 20 μg/L to 200 μg/L with a limit of detection of 5.4 μg/L. The results suggest that this system could provide a promising platform for in-situ, rapid and sensitive detection of chromium (VI) in water.