Electrochemical Determination of Fentanyl Using Carbon Nanofiber-Modified Electrodes

Abstract

In this work, we report the direct electrochemical oxidation of fentanyl using commercial screen-printed carbon electrodes (SPCEs) modified with carboxylfunctionalized carbon nanofibers (fCNFs). CNFs have surface chemistry and reactivity similar to carbon nanotubes (CNTs), yet they are easier to produce and are of a lower cost than CNTs. By monitoring the current produced during the electrochemical oxidation of fentanyl, variables such as fCNF loading, fentanyl accumulation time, electrolyte pH, and differential pulse voltammetry parameters were optimized. Under an optimized set of conditions, the fCNF/SPCEs responded linearly to fentanyl in the concentration range of 0.125−10 μM, with a limit of detection of 75 nM. The fCNF/ SPCEs also demonstrated excellent selectivity against common cutting agents found in illicit drugs (e.g., glucose, sucrose, caffeine, acetaminophen, and theophylline) and interferents found in biological samples (e.g., ascorbic acid, NaCl, urea, creatinine, and uric acid). The performance of the sensor was also successfully tested using fentanyl spiked into an artificial urine sample. The straightforward electrode assembly process, low cost, ease of use, and rapid response make the fCNF/SPCEs prime candidates for the detection of fentanyl in both physiological samples and street drugs.

Strategies for assessing the limit of detection in voltammetric methods: comparison and evaluation of approaches

“…Much work has been performed with this molecule and recent examples demonstrate its electrochemical behavior. [49][50][51][52] Aside from its clinical use, acetaminophen is also of interest in forensic applications due to its presence in the drug supply as an adulterant. [53][54][55] In comparison to ferricyanide, acetaminophen represents a more challenging analyte in terms of its electrochemical behavior.…”

Hydrothermally Synthesized Cerium Phosphate with Functionalized Carbon Nanofiber Nanocomposite for Enhanced Electrochemical Detection of Hypoxanthine

“…Synergistic effects and the electrostatic interaction (π-π-interaction) between CePO 4 and f -CNF show enhanced improvement in electrochemical sensors [11]. Functionalization provides higher sensitivity, selectivity, and increased active surface area [19]. Therefore, the f -CNF exhibits better redox properties than the pristine CNF.…”