Popis: |
Paper has been increasingly used in recent years as a substrate in the structure of sensors to determine diverse biological and pharmaceutical molecules and ions. Potentiometric sensors built with paper offer certain improvements since they are cost–effective, portable, biodegradable, eco–friendly, disposable and easy to manufacture. Paper is also an ideal substrate to be used, considering that it is flexible, lightweight, mechanically–resistant, a good medium for immobilization and trapping, and that it can be easily chemically and physically modified for customized applications, it can adsorb and transport liquid via capillary forces, can close the electrical circuit between electrodes when wet, it can be produced in diverse geometrical dimensions and porosities. Due to these characteristics, paper–based potentiometric sensors are more eco–friendly, suitable to be used in resource–limited areas, can be used in remote locations or on–site settings with low–cost analytical instrumentation. To our knowledge, the most recent advancements in the field have not been collectively reviewed, and this is of high importance considering the rapid developments made in paper–based potentiometric sensors lately. In these review, we covered paper–based potentiometric devices developed in the very recent years, detailed their structures, and compared their certain performance parameters including detection limit, linear concentration range, response time and applicability. |