Microfluidic paper-based analytical device with a preconcentration system for the measurement of anionic surfactants using an optode detector

A low-cost, simple, and sensitive on-site measurement system for anionic surfactants using a microfluidic paper-based analytical device (μPAD) with an optode has been developed. The μPAD incorporates a sample solution preconcentration system using filter paper modified with chitosan.