Determination of acetaminophen using functional paper-based electrochemical devices

In the present study, we constructed a functional paper fluidic device and evaluated its electrochemical performance by analyzing acetaminophen in the presence of ascorbic acid. The device was composed of a single-walled carbon nanotube (SWCNT) electrode and nafion-modified nitrocellulose membrane. Negatively-charged nafion was employed to build up a more negative charge on the nitrocellulose membrane, and gold nanoparticles and polyglutamic acid (AuNP-PGA) were deposited on the SWCNT electrode to enhance the electrochemical performance of the device. The device had a vertical flow format in which the sample solution flowed vertically through the paper. Using the nafion-modified nitrocellulose membrane and AuNP-PGA/SWCNT film electrode as a component of the paper fluidic device, we obtained a distinguishable acetaminophen oxidation peak which was distinct from the ascorbic acid oxidation peak. The acetaminophen oxidation peak had a linear response with acetaminophen concentration, varying from 50 μM to 300 μM (r2 = 0.992), which was broader than the standard drug dose range. The device exhibited a sensitivity of 13.3 mA/M and a detection limit of 15.0 μM. The device was stable with a relative standard deviation of 3.3% (up to 2 weeks), and the reproducibility was 1.2-5.2%. Furthermore, the fabricated device accurately measured the amount of acetaminophen in pharmaceutical samples.