An integrated phenol 'sensoremoval' microfluidic nanostructured platform.

Phenol is a widely used chemical that for several reasons may be released into the environment and, consequently, its detection and subsequent destruction into the ground and surface waters are of special importance. Herein, a simple lab-on-a-chip (LOC) device based on biocompatible and biodegradable CaCO3- poly(ethyleneimine) (PEI) nanostructured microparticles (MPs) to detect and remove phenolic wastes is proposed. The detection of phenol using a hybrid polydimethylsiloxane (PDMS)/glass chronoimpedimetric microchip and its removal in the same LOC system through the use of an extra CaCO3-PEI MPs microcolumn is achieved. For the first time, the chronoimpedance technique is applied in a LOC system for phenol sensing in a range of 0.01-10 µM achieving the limit of detection (LOD) of 4.64 nM. Moreover, this device shows a high repeatability with a relative standard deviation of 3% which is almost 4 times lower than that for the chronoamperometry technique. This LOC system represents an integrated platform for phenol sensing and removal (sensoremoval) that can be easily fabricated and is of a low cost, disposable and amenable to mass production.