Conducting polymers (CPs) are extensively studied due to their high versatility and electrical properties, as well as their high environmental stability. Based on the above, their applications as electronic devices are promoted and constitute an interesting matter of research. This review summarizes their application in common electronic devices and their implementation in electronic tongues and noses systems (E-tongues and E-noses, respectively). The monitoring of diverse factors with these devices by multivariate calibration methods for different applications is also included. Lastly, a critical discussion about the enclosed analytical potential of several conducting polymer-based devices in electronic systems reported in literature will be offered.

Monitoring of lactate is spreading from the evident clinical environment, where its role as a biomarker is notorious, to the agrifood ambit as well. In the former, lactate concentration can serve as a useful indicator of several diseases (e.g., tumour development and lactic acidosis) and a relevant value in sports performance for athletes, among others. In the latter, the spotlight is placed on the food control, bringing to the table meaningful information such as decaying product detection and stress monitoring of species. No matter what purpose is involved, electrochemical (bio)sensors stand as a solid and suitable choice. However, for the time being, this statement seems to be true only for discrete measurements. The reality exposes that real and continuous lactate monitoring is still a troublesome goal. In this review, a critical overview of electrochemical lactate (bio)sensors for clinical and agrifood situations is performed. Additionally, the transduction possibilities and different sensor designs approaches are also discussed. The main aim is to reflect the current state of the art and to indicate relevant advances (and bottlenecks) to keep in mind for further development and the final achievement of this highly worthy objective.

In this work, the development and characterization of a new ceramic material modified with polyaniline powder obtained by a high-power ultrasound sol-gel route is presented. A preliminary screening of the conducting polymer electroactivity was performed by means of cyclic voltammetry in free analyte solution. Remarkable figures of merit for 4-chloro-3-methylphenol (PCMC) determination, selected as the model organic analyte, was obtained with the developed material: the sensitivity and the limit of detection were 2.40 μA/μM·cm2 and 0.69 μM, respectively. The developed device was also successfully applied in the electrochemical determination of PCMC in water samples collected from different sources, obtaining recovery values ranging from 92% to 105%. The electrochemical performance of the device for the detection of other chlorophenols of interest was better in comparison with the bare electrode in all cases, due to the presence of the bulk modifier in the material. Therefore, the electrode material can be promoted for electrochemical assays of different chlorophenols in buffer and real water media for environmental monitoring.

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Treatment of alkynes with diethyl phosphite and t-butyl hydroperoxide in the presence of [Cu­(MeCN)4]­BF4 under microwave irradiation produced the oxyphosphorylation of the triple bond, giving rise to the corresponding β-ketophosphonates in moderate-to-good yields. When the triple bond was conjugated to a carbonyl group bearing an aromatic ring, it led to the cyclization of the resulting ketone intermediate, producing eventually different phosphonylated indenones.

In this work, a screening of Sonogel-Carbon (SNGC) electrodes modified with nanomaterials (carbon nanotubes and gold nanoparticles) and the study of their effect on the electrochemical performance of sinusoidal voltage (SV) and current (SC)-based biosensors are reported. Surface modification was achieved by drop-casting and electrodeposition methodologies. Within the strategies used, SV and SC, recently exploited procedures, were used to electrodeposit simultaneously a poly 3,4-ethylenedioxythiophene (PEDOT)-tyrosinase layer and the corresponding nanostructured material. Dopamine was selected as a benchmark analyte to evaluate the analytical performance of the different (bio)sensors obtained in terms of relevant figures of merit, such as sensitivity, limits of detection and quantitation, and accuracy, among others. A discussion about the pros and cons between the type of modification and the methods employed is also presented. Briefly, SC based sensors offered excellent quality analytical parameters and lower dispersion of the results. They were employed for more specific electrochemical studies, including interferences assays and the determination of DA in real samples, obtaining good recoveries (101–110.6%). The biosensor modified with gold nanoparticles (AuNPs) (drop-casting method) and SC-electrodeposited showed the best figures of merit: R2 = 0.999; sensitivity = −4.92 × 10−9 A·µM−1; RSDsensitivity = 1.60%; LOD = 5.56 µM; RSDLOD = 6.10%; and LOQ = 18.53 µM.

A new electrochemical sensor device has been developed through the modification of a polyaniline-silicon oxide network with carbon black (CB). Enhanced electrical conductivity and antifouling properties have been achieved due to the integration of this cheap nanomaterial into the bulk of the sensor. The structure of the developed material was characterized using Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy techniques. Cyclic voltammetry was used to characterize electrochemically the Sonogel-Carbon/Carbon Black-PANI (SNG-C/CB-PANI) sensor device. In addition, differential pulse voltammetry was employed to evaluate the analytical response of the sensor towards sundry chlorophenols, common environmental hazards in aqueous ecosystems. The modified sensor material showed excellent antifouling properties, which led to a better electroanalytical performance than the one displayed with the bare sensor. Notably, a sensitivity of 5.48 × 103 μA mM−1 cm−2 and a limit of detection of 0.83 μM were obtained in the determination of 4-chloro-3-methylphenol (PCMC) at a working potential of 0.78 V (vs. 3 M Ag/AgCl/KCl), along with proficient values of reproducibility and repeatability (relative standard deviation < 3%). Finally, the analysis of PCMC was carried out in multiple validated water samples using the synthesized SNG-C/CB-PANI sensor device, obtaining excellent results of recovery values (97–104%). The synergetic effect of polyaniline and carbon black leads to novel antifouling and electrocatalytic effects that improve the applicability of this sensor in sample analysis versus complex conventional devices. Graphical abstract

A copper-iron-based catalyst has been prepared by a low-temperature co-precipitation and sonication method. The use of high-energy ultrasound reduces the time required for the preparation process from one workweek to...