Correction: Sexual pheromone detection using PANI·Ag nanohybrid and PANI/PSS nanocomposite nanosensors.

Correction for 'Sexual pheromone detection using PANI·Ag nanohybrid and PANI/PSS nanocomposite nanosensors' by Janine Martinazzo et al., Anal. Methods, 2021, 13, 3900-3908, DOI: 10.1039/d1ay00987g.

Sexual pheromone detection using PANI·Ag nanohybrid and PANI/PSS nanocomposite nanosensors.

In this study, polyaniline/poly(styrene sulfonate) (PANI/PSS) nanocomposite and polyaniline·silver (PANI·Ag) nanohybrid thin films were obtained in cantilever nanosensors surface. The developed films were characterized in relation to topography, roughness, thickness, height, and structural properties. The topography study revealed that both films have a globular morphology, thickness and height in nanoscale. The gas sensing performance was investigated for sexual pheromone from the neotropical brown stink bug, Euschistus heros (F.). The sensitivities of both nanosensors based on PANI/PSS nanocomposite and PANI·Ag nanohybrid films were similar. The PANI·Ag nanohybrid nanosensor had a limit of detection of less than 3.1 ppq and limit of quantification of 10.05 ppq. The nanosensor layers were analyzed by UV-vis and FTIR showing the incorporation of Ag nanoparticles in the nanohybrid. We found that pheromone compound was adsorbed in sensing layer resulting in a reduction in the resonance frequency. The detection mechanism help us understand the good results of LOD, LOQ, sensitivity, selectivity and repeatability. The presented device has great potential for detection of the sexual pheromone from E. heros.

Conducting Polymer-Based Cantilever Sensors for Detection Humidity.

This paper describes the use of different conducting polymers (polyaniline, poly(o-ethoxyaniline), and polypyrrole) as a sensitive layer on a silicon cantilever sensor. The mechanical response (deflection) of the bimaterial (the coated cantilever) was investigated under the influence of relative humidity. The variations in the deflection of the coated cantilevers when exposed to relative humidity were evaluated. The results indicated a linear sensitivity in ranges, where the high value was obtained for a polypyrrole-sensitive layer between 20 and 45% of humidity. Furthermore, the sensor shows excellent performance along with rapid response and recovery times, relatively low hysteresis, and excellent stability. The sensors developed are potentially excellent materials for sensing low humidity for long time.

Tools for detecting insect semiochemicals: a review.

Semiochemicals are chemical compounds that are released by many species as a means of intra- and interspecific communication. Insects have extremely advanced olfactory systems; indeed, they rely on smell when performing many of their main behaviors, such as oviposition, breeding, prey location, and defense. This characteristic of insects implies that semiochemicals could be used for various applications, including in agriculture, where they could be employed along with other tools to control pest insects. The aim of this review is to present the main techniques used and the state of the art in the detection of semiochemicals, focusing on pheromones. In addition to the traditional methods of identifying semiochemicals, such as gas chromatography coupled to a high-resolution detection mode (e.g., flame ionization (FID), electron capture (ECD), photoionization (PID), or mass spectrometry (MS)), other tools are addressed in this review, including sensors and biosensors. While these new technologies may be used under laboratory conditions to improve or complement technologies that are already being used, they are mainly intended for use as new agricultural tools for detecting and controlling pest insects in the field.

Cantilever Functionalization Using Peroxidase Extract of Low Cost for Glyphosate Detection.

A cantilever nanobiosensor functionalized with vegetable source of peroxidase was developed as an innovative way for glyphosate herbicide detection over a wide concentration range (0.01 to 10 mg L-1) using atomic force microscopy (AFM) technique. The extract obtained from zucchini (Cucurbita pepo source of peroxidase), with high enzymatic activity and stability has been used as bio-recognition element to develop a nanobiosensor. The polarization-modulated reflection absorption infrared spectroscopy (PM-RAIRS) demonstrated the deposition of enzyme on cantilever surface using self-assembled monolayers (SAM) by the presence of the amide I and II bands. The detection mechanism of glyphosate was based on the changes in surface tension caused by the analyte adsorption, resulting in a conformational change in the enzyme structure. In this way, the results of nanobiosensor demonstrate the potential of the sensing device for detecting glyphosate with a detection limit of 0.028 mg L-1.