Voltammetric and Impedimetric Detection of Norfloxacin at Co Nanoparticle Modified Polymer Composite Electrodes

Abstract

The measurement of antibiotics in environmental water systems is increasingly becoming a top priority for global environmental watchdog organisations, as the looming threat of emerging contaminants moves to centre stage. A novel chemical sensor based on polyamic acid (PAA) semiconducting polymer and cobalt nanoparticles (CoNP) was developed and used to demonstrate proof of concept evidence for measurement of norfloxacin at trace concentrations in aqueous systems. Polyamic acid and cobalt nanoparticles were both chemically synthesised and characterised using Fourier transform infrared spectroscopy, transmission electron microscopy, cyclic voltammetry and small angle x-ray scattering. The polyamic acid and cobalt nanoparticles were electrodeposited onto screen printed carbon electrodes to produce novel composite sensors (SPCE/PAA/CoNP). The polymer composite chemical sensors were applied to the detection of norfloxacin in the micromolar concentration using square wave voltammetry, with a sensitivity of 18.0 � 6.59 μA/mM, calculated from the slope of the calibration curve and a limit of detection (LOD) of 0.979 � 0.419 mM, with LOD = 3.3(Sy/S). The SPCE/PAA/ CoNP sensor response to norfloxacin as measured by electrochemical impedance spectroscopy, yielded a sensitivity of 17.6 � 8.72 Ω/mM as and a limit of detection (LOD) of 0.228 � 0.0935 mM.

Validation of a Novel RP-HPLC Technique for Simultaneous Estimation of Lignocaine Hydrochloride and Tibezonium Iodide: Greenness Estimation Using AGREE Penalties

“…The LOD and the LOQ were identified by dividing the standard deviation (Sy) value obtained from the lowest concentrations of analyte prepared for determining the linearity range with the slope of the linearity line (S). Equations ( 4) and (5) were used for estimating LOD and LOQ parameters, respectively, for TBN and LGN [38].…”

Electrochemical Sensing Platform Based on Graphene Oxide‐chitosan for Simultaneous Determination of some Antihypertensive Drugs

“…The Nyquist plane plot of GO-CS/GCE was a straight line in the low frequency region, indicating a lower resistance than the bare electrode. This trend can be a result of two issues: (i) the large surface area of GO nasnosheets that resulted in the improvement current response and (ii) the electrostatic attraction between anionic probe ([Fe(CN) 6 ] À 3/À 4 ) and the positively charged amine residues of CS backbone, leading to an enhancement of [Fe(CN) 6 ] À 3/À 4 diffusion to the modified electrode surface [14]. Considering the small value of ΔEp and larger current response at modified electrode, it seems that charge transfer is quasi-reversible and fast, indicating the ability of this nanocomposite to produce a favorable microenvironment to face facile electron-transfer reaction.…”

“…On the other hand, electroanalytical methods, in particular, have been applied for the determination of electroactive species [12]. They are powerful alternative methods for the analysis of pharmaceuticals due to their operation simplicity, rapidity, cost-effective and economical features [13][14].…”

Molecular-electromechanical system for unamplified detection of trace analytes in biofluids

“…LoD, defined as the lowest quantity or concentration of a component that can be reliably detected with a given analytical method, is the key index representing the detection capability. The typical way to calculate the LoD is based on the standard deviation of the response (S y ) of the curve and the slope of the calibration curve (S) at levels approximating the LoD according to the formula: LoD = 3.3(S y /S) 125 . However, the LoD obtained from this approach is usually beyond the physical detection limit when considering the sample volume.…”