Rapid and wide-range determination of Cd(II), Pb(II), Cu(II) and Hg(II) in fish tissues using light addressable potentiometric sensor

•A novel method based on LAPS is firstly used to detect heavy metals in fish.•Digestion influence with LAPS method is investigated, and best factors are found.•Good linearity and measurement range are obtained in detection of Cd, Pb, Cu and Hg.

A rapid and wide-range method, based on light addressable potentiometric sensor (LAPS), is introduced into determination of Cd(II), Pb(II), Cu(II) and Hg(II) in fish tissues. A compact LAPS module is prepared by integrating four LAPS chips specifically sensitive to target elements. Its responses in digestions from various settings are investigated to find suitable factors. Analytical properties of this method are evaluated in consequent experiments under optimized conditions. Measurement range for each target element exceeds 0.1 to 1000 mg L−1, and response time is less than 10 s. Accuracy, precision and selectivity of the proposed method are also well defined in measurements. It is successively performed to detect the target elements in real fish samples from 4 species, and obtained results are consistent with certified method.