Anal. Chem. http://doi.org/c5z9 (2019)

Perfluorinated surfactants are harmful, so their quantification in water is necessary. However, the existing ways of surfactant detection are complicated and not environmentally friendly. Now Luo and co-workers reported a simple bubble-nucleation-based electrochemical method to quantify surfactants selectively and sensitively.

They previously reported Pt nanodisk electrodes that are capable of monitoring the electrogeneration of single hydrogen bubbles at the Pt/gas/liquid interface from the drop of the diffusion-limited current in a hydrogen evolution reaction. By scanning the electrode potential, a minimum current value corresponding to the bubble nucleation and formation was reached. The high surface activity of surfactants is known to enable bubbles to nucleate at much lower dissolved H2 level. Then by measuring the peak value, they demonstrate the quantification of surfactant in water. With a preconcentration step, they achieve a limit of detection of 70 ng l–1, the advised value for drinking water.