Pt nanoparticles supported on nitrogen doped reduced graphene oxide-single wall carbon nanotubes as a novel platform for highly sensitive electrochemical sensing of piroxicam

Fabrication of a novel sensor based on Cu quantum dot and SH-SiO2 nanoparticles supported on copper-based metal organic framework (Cu QD-SH-SiO2@Cu-MOF) and its application for the simultaneous determination of norepinephrine, piroxicam and epinephrine

In this research, a novel electrochemical sensor with excellent sensitivity was fabricated based on Cu quantum dot (Cu QD) and SH-SiO2 nanoparticles immobilized on copper-metal-organic frameworks (Cu-MOFs) for determining piroxicam and simultaneous determination of norepinephrine, piroxicam and epinephrine. The nanoparticles were synthesized and characterized using FT-IR, EDX, FESEM, TEM and BET, and were subsequently used to modify carbon paste electrode. Cu QD-SH-SiO2@Cu-MOF for electrode modification possesses a distinctive structure and a high conductivity that raises the electron transfer rate and enhances the performance of electrochemical sensors. Square wave voltammetry was applied to investigate the redox properties of Cu QD-SH-SiO2@Cu-MOF/CPE, voltammograms showed three distinct anodic peaks at 0.41, 0.62 and 1.06 V in the presence of norepinephrine, piroxicam, and epinephrine. Various experimental parameters including the type and pH of electrolyte and scan rate were investigated. The calibration graph was obtained over the range 0.2-34285.0 μM including three linear segments. Also, the limit of detection was calculated as 0.05 μM of piroxicam. The introduced sensor was satisfactorily utilized for electrochemical determination of norepinephrine, piroxicam, and epinephrine in real samples. The obtained results using the introduced sensor were validated by high-performance liquid chromatography and the statistical tests confirmed the good agreement of them.

Recent Advances in Metal Nanocomposite-Based Electrochemical (Bio)Sensors for Pharmaceutical Analysis

Rising rates of drug abuse and pharmaceutical pollution throughout the world as a consequence of increased drug production and utilization pose a serious risk to public health and to environmental integrity. It is thus critical that reliable analytical approaches to detecting drugs and their metabolites in a range of sample matrices be developed. Recent advances in the design of nanomaterial-based electrochemical sensors and biosensors have enabled promising new approaches to pharmaceutical analysis. In particular, the development of a range of novel metal nanocomposites with enhanced catalytic properties has provided a wealth of opportunities for the design of rapid and reliable platforms for the detection of specific pharmaceutical compounds. The present review provides a comprehensive overview of representative metal nanocomposites with synergistic properties and their recent (2017-2022) application in the context of electrochemical sensing as a means of detecting specific antibiotic, tuberculostatic, analgesic, antineoplastic, antipsychotic, and antihypertensive drugs. In discussing these applications, we further explore a variety of testing-related principles, fabrication approaches, characterization techniques, and parameters associated with the sensitivity and selectivity of these sensor platforms before surveying the future outlook regarding the fabrication of next-generation (bio)sensor platforms for use in pharmaceutical analysis.

Synthesis and electrochemical properties of environmental free l-glutathione grafted graphene oxide/ZnO nanocomposite for highly selective piroxicam sensing

A simple and reliable strategy was proposed to engineer the glutathione grafted graphene oxide/ZnO nanocomposite (glutathione-GO/ZnO) as electrode material for the high-performance piroxicam sensor. The prepared glutathione-GO/ZnO nanocomposite was well characterized by X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The novel nanocomposite modified electrode showed the highest electrocatalytic activity towards piroxicam (oxidation potential is 0.52 V). Under controlled experimental parameters, the proposed sensor exhibited good linear responses to piroxicam concentrations ranging from 0.1 to 500 μM. The detection limit and sensitivity were calculated as 1.8 nM and 0.2 μA/μM·cm2, respectively. Moreover, it offered excellent selectivity, reproducibility, and long-term stability and can effectively ignore the interfering candidates commonly existing in the pharmaceutical tablets and human fluids even at a higher concentration. Finally, the reported sensor was successfully employed to the direct determination of piroxicam in practical samples.