Highly Sensitive Determination of Tenofovir in Pharmaceutical Formulations and Patients Urine—Comparative Electroanalytical Studies Using Different Sensing Methods

Abstract

This paper discusses the electrochemical behavior of antiviral drug Tenofovir (TFV) and its possible applicability towards electroanalytical determination with diverse detection strategies using square-wave voltammetry. Namely, oxidation processes were investigated using glassy carbon electrode with graphene oxide surface modification (GO/GCE), while the reduction processes, related to the studied analyte, were analyzed at a renewable silver amalgam electrode (Hg(Ag)FE). Scanning electron microscopy imaging confirmed the successful deposition of GO at the electrode surface. Catalytic properties of graphene oxide were exposed while being compared with those of bare GCE. The resultant modification of GCE with GO enhanced the electroactive surface area by 50% in comparison to the bare one. At both electrodes, i.e., GO/GCE and Hg(Ag)FE, the TFV response was used to examine and optimize the influence of square-wave excitation parameters, i.e., square wave frequency, step potential and amplitude, and supporting electrolyte composition and its pH. Broad selectivity studies were performed with miscellaneous interfering agents influence, including ascorbic acid, selected saccharides and aminoacids, metal ions, non-opioid analgesic metamizole, non-steroidal anti-inflammatory drug omeprazole, and several drugs used along with TFV treatment. The linear concentration range for TFV determination at GO/GCE and Hg(Ag)FE was found to be 0.3–30.0 µmol L–1 and 0.5–7.0 µmol L–1, respectively. The lowest LOD was calculated for GO/GCE and was equal to 48.6 nmol L–1. The developed procedure was used to detect TFV in pharmaceutical formulations and patient urine samples and has referenced utilization in HPLC studies.

Fast and Ultrasensitive Electrochemical Detection for Antiviral Drug Tenofovir Disoproxil Fumarate in Biological Matrices

“…Combined with the conclusion obtained from the pH, it can be seen that the electrochemical oxidation of TDF on the electrode is a two-electron and two-proton transfer process. According to the existing reports on the oxidation mechanism of TFV (of which TDF is a precursor) [ 65 , 66 ], it can be speculated that the oxidation mechanism of TDF on ZrO 2 -CS-MWCNTs/GCE is as shown in Figure S4 .…”

Detection and quantification of antiviral drug tenofovir using silver nanoparticles and surface enhanced Raman spectroscopy (SERS) with spatially resolved hotspot selection

“…This approach offers a considerable advantage over conventional methods such as LC-MS/MS, which involve complex instrumentation and sample preparation (Lin et al, 2023). Other methods of detection of aqueous TFV include squarewave voltammetry where Festinger and coworkers reported limits of detection as low as 1.35 × 10 −7 M (39 ng/mL) and 4.86 × 10 −8 M (14 ng/ mL) (Festinger et al, 2022). Chiral separation phase (CSP) LCMS of enantiomeric mixtures of a prodrug form of tenofovir, tenofovir disoproxil fumarate (TDF), reported limits of detection of 1.5 ng/ mL and 1.2 ng/mL for the R-and S-TDF enantiomers, respectively (Lin et al, 2023).…”

An ALP enzyme-based electrochemical biosensor coated with signal-amplifying BaTiO3 nanoparticles for the detection of an antiviral drug in human blood serum

“…23 Nanomaterial based modications are gaining popularity due to their unique characteristics such as fast electron transfer, nanosize, stability, energy efficiency, and catalytic performance. 24 Some studies have explored the electrochemical detection of TFV drugs using nanomaterials: Xiao et al reported ZrO 2 -CS-MWCNTs/GCE, 2 Mehmandoust et al reported MIP-PT@g-C 3 N 4 /F-MWCNT, 9 Alake et al developed an electrode with NiS@PAA-MWCNT, 13 Zeng et al used La 2 O 3 -ZrO 2 -MWCNTs/ GCE, 11 Festinger et al proposed GO/GCE and Hg(Ag)FE, 25 and Ozcelikay et al utilized benzalkonium chloride/AgNPs. 26 It is imperative to conduct a thorough assessment in order to obtain accurate and timely detection of the TFV drug with a costeffective and feasible implementation.…”