Disposable Multiwall Carbon Nanotubes Based Screen Printed Electrochemical Sensor With Improved Sensitivity for the Assay of Daclatasvir: Hepatitis C Antiviral Drug

Disposable all solid-state screen printed ion selective electrode was developed for the assay of daclatasvir (DCV) in pharmaceutical formulation and spiked human urine. The sensor is based on daclatasvir-tetraphenyl borate (DCV-TPB) as a sensing element. Incorporation of the multiwall carbon nanotubes (MWCNTs) into the ion selective membrane was found to influence the sensor sensitivity. The MWCNTs containing membrane exhibited a Nernstian slope of 31.0±1 mV/decade over a wide concentration range from $1 \times 10^{-5}$ to $1 \times 10^{-2}$ M DCV (r 2 = 0.9999) with a LOD of $8.5 \times 10^{-7}$ M in a pH 3.3 compared to a slope of 27.5 ± 1 mV/decade, over the concentration range from $1 \times 10^{-4}$ to $1 \times 10^{-2}$ M DCV for MWCNTs-free ion selective membrane. The response time of the electrode was $\le 0.23~\mu \text{V}$ /min against $330.0~\mu \text{V}$ /min for a coated glassy carbon electrode. Further characterizations, including reproducibility, chronopotentiometry, and selectivity were examined. The electrode showed high selectivity to DCV against the common interfering compounds. The electrode was applied for the assay of daclatasvir in pharmaceutical formulation and spiked urine sample with a high accuracy (±2%) and precision (%RSD <2).