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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.

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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.

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Heavy metals can be highly toxic depending on the dose and the chemical form. In this context, sensing devices such as nanobiosensors have been presented as a promising tool to monitor contaminants at micro and nanoscale. In this work, cantilever nanobiosensors with phosphatase alkaline were developed and applied to detect heavy metals (Pb, Ni, Cd, Zn, Co, and Al) in river water. The nanobiosensor surface was functionalized by the self-assembled monolayers (SAM) technique using 16-mercaptohexadecanoic acid, N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) and N- hydroxysuccinimide (NHS), and phosphatase alkaline enzyme. The sensing layer deposited on the cantilever surface presented a uniform morphology, at nanoscale, with 80 nm of thickness. The nanobiosensor showed a detection limit in the ppb range and high sensitivity, with a stability of fifteen days. The developed cantilever nanobiosensor is a simple tool, suitable for the direct detection of contaminants in river water.

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This work aimed to develop cantilever nanobiosensor functionalized with tyrosinase enzyme to detect 17ß-estradiol and estrone hormones. In this system, the tyrosinase enzyme was covalently immobilized by self-assembled monolayer onto the cantilever sensor surface. It was possible to verify that the high hormone concentration investigated resulted in high voltage response. The nanobiosensor presented a distinction between the concentrations evaluated and was verified sensitivities of 0.497 and 0.101 V/µg, limit of detection of 0.1 and 0.4 ng/L for the hormones 17ß-estradiol and estrone, respectively. The device showed good reversibility and during 30 days of storage maintained about 99% of the original signal. The cantilever nanobiosensor applied in different water samples (ultrapure, river, tap, and mineral) showed good performance, so could be readily extended toward the on-site monitoring of the other trace small molecular pollutants in environmental water matrices.

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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.

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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.

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The aim of this study was to develop a cantilever nanobiosensor for atrazine detection in liquid medium by immobilising the biological recognition element (tyrosinase vegetal extract) on its surface with self-assembled monolayers using gold, 16-mercaptohexadecanoic acid, 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride/n-hydroxysuccinimide. Cantilever nanobiosensors presented a surface compression tension increase when atrazine concentrations were increased, with a limit of detection and limit of quantification of 7.754 ppb (parts per billion) and 22.792 ppb, respectively. From the voltage results obtained, the evaluation of atrazine contamination in river and drinking water were very close to those of the reference sample and ultrapure water, demonstrating the ability of the cantilever nanobiosensor to distinguish different water samples and different concentrations of atrazine. Cantilever nanosensor surface functionalization was characterised by combining polarisation modulation infrared reflection-absorption spectroscopy and atomic force microscopy and indicating film thickness in nanometric scale (80.2 ± 0.4 nm). Thus, the cantilever nanobiosensor developed for this study using low cost tyrosinase vegetal extract was adequate for atrazine detection, a potential tool in the environmental field.

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The menopause is the stage of a woman's life when the transition from the reproductive to the non-reproductive condition occurs. The objective was to conduct a nutritional assessment of 30 postmenopausal women aged between 40 and 65, by compiling data from the first consultation of nutritional records related to food intake, as well as anthropometric and biochemical data. It was observed that the average result found for body mass index was considered high, being characterized as overweight (30.7 ± 5.9kg/m2) and waist circumference revealed a very high risk for developing cardiovascular disease (98.2 ± 15.9cm). Saturated fats were above the recommended level (8.14 ± 3.63%), whereas monounsaturated and polyunsaturated fats were lower resulting in 6.47 ± 3.40% and 5.37 ± 2.60% respectively. The average calcium intake was 549.63 ± 315.87mg, while vitamin D intake was 549.63 ± 315.87mcg, both of which were considered inadequate. Triglycerides were classified as optimal (134,3 ± 85,4mg/dL), total cholesterol was borderline (223.9 ± 141.3md/dL), HDL-C adequate (54.3 ± 18.5mg/dL) and LDL-C desirable (128.4 ± 45.1mg/dL). The results demonstrate that nutritional care is important and can prevent specific comorbidities in this age group, contributing to the quality of life of menopausal women.

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O climatério é a fase da vida da mulher em que ocorre a transição do período reprodutivo para o não reprodutivo. O objetivo da pesquisa foi realizar a avaliação nutricional de 30 mulheres no climatério com idades entre 40 e 65 anos, compilando os dados da primeira consulta dos prontuários nutricionais referentes ao consumo alimentar, dados antropométricos e bioquímicos. Observou-se que o resultado médio encontrado para o Índice de Massa Corporal foi considerado elevado, caracterizando excesso de peso (30,7 ± 5,9kg/m2) e a circunferência da cintura apresentou risco muito alto para desenvolver doenças cardiovasculares (98,2 ± 15,9cm). As gorduras saturadas estiveram acima do preconizado (8,14 ± 3,63%), enquanto que as gorduras mono e poli-insaturada estiveram abaixo, resultando em 6,47 ± 3,40% e 5,37 ± 2,60%, respectivamente. O consumo médio de cálcio foi de 549,63 ± 315,87mg, já o de vitamina D, 549,63 ± 315,87mcg e ambos estiveram inadequados. Os triglicerídeos foram classificados como ótimos (134,3 ± 85,4mg/dL), o colesterol total limítrofe (223,9 ± 141,3md/dL), o HDL-C adequado (54,3 ± 18,5mg/dL) e o LDL-C desejável (128,4 ± 45,1mg/dL). Os resultados demonstram que o cuidado nutricional é importante, podendo prevenir comorbidades específicas desta faixa etária, contribuindo para a qualidade de vida das mulheres climatéricas.

The menopause is the stage of a woman's life when the transition from the reproductive to the non-reproductive condition occurs. The objective was to conduct a nutritional assessment of 30 postmenopausal women aged between 40 and 65, by compiling data from the first consultation of nutritional records related to food intake, as well as anthropometric and biochemical data. It was observed that the average result found for body mass index was considered high, being characterized as overweight (30.7 ± 5.9kg/m2) and waist circumference revealed a very high risk for developing cardiovascular disease (98.2 ± 15.9cm). Saturated fats were above the recommended level (8.14 ± 3.63%), whereas monounsaturated and polyunsaturated fats were lower resulting in 6.47 ± 3.40% and 5.37 ± 2.60% respectively. The average calcium intake was 549.63 ± 315.87mg, while vitamin D intake was 549.63 ± 315.87mcg, both of which were considered inadequate. Triglycerides were classified as optimal (134,3 ± 85,4mg/dL), total cholesterol was borderline (223.9 ± 141.3md/dL), HDL-C adequate (54.3 ± 18.5mg/dL) and LDL-C desirable (128.4 ± 45.1mg/dL). The results demonstrate that nutritional care is important and can prevent specific comorbidities in this age group, contributing to the quality of life of menopausal women.

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