Inkjet-printed low-cost colorimetric tickets for TNT detection in contaminated soil

摘要

A simple colorimetric detection method for 2,4,6-trinitrotoluene (TNT) in contaminated soil has been developed. Procedurally, a TNT responsive chromogenic reagent was inkjet printed on commercially available photo paper, and the resulting colorimetric ticket was laminated with a precut patterned film to make a bilayer microfluidic sensor. For the TNT detection experiments, a drop of TNT solution was placed on the center of the prepared sensor. Color measurement of the sensor with a photo scanner showed a wide detection range of TNT, ranging from 14 parts per million (ppm), which is below its residential screening level (similar to 21 ppm) to 7,200 ppm. To further demonstrate its efficacy, TNT spiked soil samples were extracted with acetone and evaluated with the developed sensor.