부산대학교 도서관

According to the World Health Organisation, worldwide waterborne diseases are responsible for nearly two million human deaths annually. Rapid and at-site screen of pathogenic microorganisms in drinking water can help to markedly reduce this number. Here we report an innovative, simple and low-cost, paper-based probe for detection of bacteria in water, fabricated by screen printing carbon electrodes onto hydrophobic paper. Electrochemical characterization of the printed electrodes confirmed fast-electron transfer, with an estimated electroactive surface area of 0.25 cm 2 . The electrode surface was functionalised with carboxyl groups, prior to covalent immobilization of the lectin Concanavalin A (Con A), used as the biorecognition element. The system was then tested as an impedimetric sensor for bacteria in water. A linear increase in the probe charge transfer resistance was observed for bacterial concentrations ranging from 10 3 to 10 6  CFU mL −1 , with an estimated lower detection limit of 1.9 × 10 3  CFU mL −1 . Considering its remarkable simplicity, cost-effectiveness and biodegradability, the sensor here reported could be an attractive solution for portable testing kits that address the challenges of traditional time-consuming and expensive lab-based analyses. [ABSTRACT FROM AUTHOR]