Electrochemical Behavior of Janus Kinase Inhibitor Ruxolitinib at a Taurine-Electropolymerized Carbon Paste Electrode: Insights into Sensing Mechanisms

Ruxolitinib (RXL) is a Janus kinase inhibitor used for treating intermediate- or high-risk myelofibrosis. This study presents an electrode modified with electrochemically polymerized taurine on a carbon paste electrode via cyclic voltammetry (CV). The surface characterization of the poly(taurine)-CP electrode was evaluated by using electrochemical (electrochemical impedance spectroscopy─EIS, CV), morphological (scanning electron microscope─SEM), and spectroscopic (Fourier-transform infrared spectroscopy─FT-IR) techniques. Under optimized conditions, RXL exhibited good linearity within the 0.01-1.0 μM concentration range, with a limit of detection (LOD) of 0.005 μM. The proposed electrochemical sensor demonstrated excellent selectivity, accuracy, precision, and repeatability. Furthermore, it effectively detected RXL in human urine and pharmaceutical samples.

Graphene oxide-manganese oxide composite as an electrocatalyst for simultaneous detection of manganese- and chromium-contaminated water

The development of a sensitive and selective electrochemical sensor for simultaneous quantification of manganese (Mn(II)) and chromium (Cr(VI)) using composite of graphene oxide (GO) and manganese oxide modified screen printed carbon electrode (GO-Mn2O3/SPCE) is reported for the first time. The good sensing performance is achieved by mixing GO prepared by modified Hummer's method (GO-H) with proper particle size of Mn2O3 (241 nm). The mechanism of this sensor is based on the formation of Mn-O and Cr-O on the modified electrode with assistance of oxygen moieties provided by both Mn2O3 NPs and GO. The analytical performances were investigated by measuring electrochemical signal of Mn(II) and Cr(VI) by using square-wave cathodic stripping voltammetry (SWCSV). This sensor holds low electrode-to-electrode variation (relative standard deviation (RSD) < 4%) with a good limit of detection (LOD) at about 6.67 and 11.20 μg⋅L-1 for Mn(II) and Cr(VI), respectively. Applicability of this sensor was demonstrated by measuring Mn(II) and Cr(VI) in tap water samples with recovery of 90.77-103.45% and 82.34-103.73% for Mn(II) and Cr(VI) determinations, respectively. With the contribution of both GO and Mn2O3 as electrocatalysts, this developed sensor is capable to be used for water quality monitoring in real samples.

An amperometric immunosensor for detection of Streptococcus suis serotype 2 using a nickel–gold nanocomposite as a tracer matrix

For quick, sensitive detection of SS2, a simple sandwich-type amperometric immunosensor was developed. A complex between AuNCs and NiHCFNPs acted as an Ab2 substrate and signal probe, as well as an AA oxidation catalyst to amplify the response signal.

Preparation and electrochemical performances of hexacyanoferrate-doped poly(3,4-ethylenedioxythiophene) hydrogel

In this article, potassium hexacyanoferrate (K3Fe(CN)6) was introduced into poly(3,4-ethylenedioxythiophene) (PEDOT) hydrogel by in situ polymerization to prepare K3Fe(CN)6-doped PEDOT hydrogel. The specific capacitance of PEDOT hydrogel was efficiently increased by the doping effect of K3Fe(CN)6. The increase in capacitance achieved by introducing K3Fe(CN)6 into PEDOT hydrogel was attributed to the doping effect of anionic ferricyanide/ferrocyanide couple. The specific capacitance of PEDOT hydrogel increased from 38 F g−1 to the maximum value of 98 F g−1 (current density = 500 mA g−1) when the concentration of K3Fe(CN)6 reached 5 mM. On the basis of cycle life tests, the capacitance retention of about 75% for the doped PEDOT hydrogel after 5000 cycles suggested a high cycle stability of redox-active PEDOT hydrogel and its potential as an electrode material for supercapacitor applications.

Polythiophenes and polythiophene-based composites in amperometric sensing

This overview of polythiophene-based materials provides a critical examination of meaningful examples of applications of similar electrode materials in electroanalysis. The advantages arising from the use of polythiophene derivatives in such an applicative context is discussed by considering the organic conductive material as such, and as one of the components of hybrid materials. The rationale at the basis of the combination of two or even more individual components into a hybrid material is discussed with reference to the active electrode processes and the consequent possible improvements of the electroanalytical performance. In this respect, study cases are presented considering different analytes chosen among those that are most frequently reported within the classes of organics and inorganics. The use of a polythiophene matrix to stably fix biological elements at the electrode surface for the development of catalytic biosensors and genosensors is also discussed. Finally, a few possible lines along which the next research in the field could be fruitfully pursued are outlined. Furthermore, the work still to be done to exploit the possibilities offered by novel products of organic synthesis, even along paths already traced in other fields of electrochemistry, is discussed.