Microfluidic paper-based analytical devices and electromembrane extraction; Hyphenation of fields towards effective analytical platforms.

Herein, the applicability of electromembrane extraction (EME), as an efficient and paper-compatible separation technique, was envisaged over customized microfluidic paper-based analytical devices (μPADs). The utility of EME was assessed on 2D planar and 3D origami structures using different types of electrodes including stainless steel and paper-based electrodes. The overall separation procedure was integrated to colorimetric detection demonstrated for copper ions as the model analyte. According to the obtained results, EME based on 3D design of μPADs could effectively be performed under low applied voltage. Using 3D architecture, the analyte could be quantified within the range of 40.0-1500.0 μg L with limit of detection down to 20.0 μg L using smart phone camera as signal read-out. The proposed platform showed remarkable compatibility with direct analysis from untreated real samples of human blood and spring water.