In this study, we report a facile and effective production process of palladium nanoparticles supported on polypyrrole/reduced graphene oxide (rGo/pd@ppy nps). A novel electrochemical sensor was fabricated by incorporation of the prepared nps onto glassy carbon electrode (Gce) for the simultaneous detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA). the electrodes modified with rGO/Pd@PPy NPs were well decorated on the GCE and exhibited superior catalytic activity and conductivity for the detection of these molecules with higher current and oxidation peak intensities. Simultaneous detection of these molecules was achieved due to the high selectivity and sensitivity of rGo/pd@ppy nps. for each biomolecule, well-separated voltammetric peaks were obtained at the modified electrode in cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements. Additionally, the detection of these molecules was performed in blood serum samples with satisfying results. the detection limits and calibration curves for AA, DA, and UA were found to be 4.9 × 10 −8 , 5.6 × 10 −8 , 4.7 × 10 −8 M (S/n = 3) and ranging from 1 × 10 −3 to 1.5 × 10 −2 M (in 0.1 M PBS, pH 3.0), respectively. Hereby, the fabricated rGO/Pd@PPy NPs can be used with high reproducibility, selectivity, and catalytic activity for the development of electrochemical applications for the simultaneous detection of these biomolecules.

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The ultimate aim of this study is to produce a composite of bimetallic platinum-cobalt nanoparticles and reduced graphene oxide (Pt-Co@rGO) based biosensor for the detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA). Those are biologically important molecules with the key functions for the human body. Pt-Co@rGO was synthesized using a microwave-assisted technique and utilized for the production of a highly sensitive and stable electrochemical biosensor. Detailed spectral XPS and Raman analysis, XRD, and TEM/HR-TEM characterization were also studied. Due to the superior activity and excellent conductivity of rGO, well-separated oxidation peaks of these biomolecules is proven by DPV (differential pulse voltammetry) and CV (cyclic voltammetry) measurements. The prepared Pt-Co@rGO-based biosensor showed high electrochemical activity, a broad linear response, high sensitivity, and acceptable limit of detection values for individual and simultaneous determination of AA, DA, and UA, under optimized conditions. The linear range of Pt-Co@rGO was found to be 170–200; 35–1500 and 5–800 µM for AA, DA, and UA, respectively. Moreover, the detection limit of the prepared composite was calculated as 0.345; 0.051; 0.172 µM for AA, DA, and UA, respectively. In the field of electrochemical biosensors, Pt-Co@rGO based sensor is highly promising due to its superior sensitivity and good selectivity properties.

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Carbon nanotubes (CNT) and graphene are two significant carbon based nanomaterials which have extraordinary physicochemical properties, used in diverse fields of research. Recently, some actual studies were made to associate these carbon nanomaterials to produce CNT‐graphene hybrid with synergic effects of graphene and CNTs. Addressed herein, EDOT‐modified reduced graphene oxide (rGO), functionalized multiwalled carbon nanotube (f‐MWCNT) and hybrid material (rGO‐f‐MWCNT) have been prepared. Then, PEDOT‐modified composite films were synthesized via electrochemical polymerization to examine enhancing electrochemical properties of PEDOT and characterized by SEM, AFM analysis. As a conclusive finding, an improved stability, charge density, electrochromic switching kinetics and optical contrast of polymer composite films were observed on presence of nanocarbon materials in comparison to the control PEDOT film due to facile ion transport, high surface area.