Fabrication of carbon nanotube-based pH sensor for paper-based microfluidics

A low-cost flexible pH sensor array for wound assessment

“…Recently, there has been an increasing interest in the low-cost paper based analytical systems, which are not only flexible but can also be disposed and recycled [14]. Two groups have recently reported on paper-based resistive [15] and potentiometric [16] pH sensors. The resistive one uses a simple fabrication process for printing carbon nanotubes on paper and uses their nonlinear response to [H] + for measuring pH.…”

Application of curcumin nanoparticles in a lab-on-paper device as a simple and green pH probe

“…Many examples of pH sensors have been reported [29][30][31][32][33][34][35][36] in literature but only a few attempts have been made to pH sensing using paper devices [37][38][39]. Abe et al have reported the simultaneous sensing of pH, total protein and glucose in urine samples using an inkjet printed microfluidic multianalyte chemical sensing paper device.…”

“…In a different approach, Lei et al proposed a carbon nanotube (CNT) based sensor on paper for the determination of pH in the range of 5-9. In the research of this group, pH measurement was based on decreasing of the resistance change with increasing the pH of the solution [37]. Various types of nanoparticles have been used in paper-based devices [12].…”

New Functionalities for Paper-Based Sensors Lead to Simplified User Operation, Lower Limits of Detection, and New Applications

“…In all of these cases, complexing agents, nanoparticles, or enzymes were used to generate a visible color change. Electrochemical methods have also been used to detect a wide range of targets on 2D PADs, including antibiotics (87), gases (88,89), metals (90), pH (91), and proteins (10, 92). Physical parameters, such as force (93), infrared (94) and UV (95) light, strain (96), and temperature and humidity (97), have also been detected electrochemically.…”