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There is increasing interest in developing portable technologies to detect human health threats through hybrid materials that integrate specific bioreceptors. This work proposes an electrochemical approach for detecting 3-Phenoxybenzaldehyde (3-PBD), a biomarker for monitoring human exposure to pyrethroid pesticides. The biosensor uses laccase enzymes as an alternative recognition element by direct oxidation of 3-PBD catalysts by the enzyme onto thin-film gold electrodes. The thin-film gold electrode modified by the immobilized laccase was characterized by Fourier-transform infrared spectrometry and scanning electron microscopy. The detection method’s electrochemical parameters were established, obtaining a linear range of 5 t 50 μM, the limit of detection, and quantification of 0.061 and 2.02 μM, respectively. The proposed biosensor’s analytical performance meets the concentration of pyrethroids detected in natural environments, reflecting its potential as an alternative analytical tool for monitoring the pyrethroid insecticide’s presence.

Despite the increasing number of reports that relate antimicrobial chlorophene (CP) with health and environmental effects, few studies have addressed biosensing technologies to detect this threat. This work proposed an electrochemical approach for the detection of CP using laccase enzymes as an alternative recognition element immobilized onto thin-film gold electrodes. The electrochemical parameters of the detection method, under controlled conditions, resulted in a limit of detection (0.14 ± 0.06 mg L−1) and quantification (0.48 ± 0.04 mg L−1) that agreed with concentrations of CP that already had been measured in natural water samples. Nevertheless, during the analysis of natural river water samples, the provided method suffered a drawback due to matrix effects reflected in the obtained recovery percentage, the value of which was 62.0 ± 2.4% compared to the 101.3 ± 3.5% obtained by the HPLC reference method. These detrimental effects were mainly attributed to organic matter, SO4-2, and Cl- present in river samples.

Chlorophene is an important antimicrobial agent present in disinfectant products which has been related to health and environmental effects, and its detection has been limited to chromatographic techniques. Thus, there is a lack of research that attempts to develop new analytical tools, such as biosensors, that address the detection of this emerging pollutant. Therefore, a new biosensor for the direct detection of chlorophene in real water is presented, based on surface plasmon resonance (SPR) and using a laccase enzyme as a recognition element. The biosensor chip was obtained by covalent immobilization of the laccase on a gold-coated surface through carbodiimide esters. The analytical parameters accomplished resulted in a limit of detection and quantification of 0.33 mg/L and 1.10 mg/L, respectively, fulfilling the concentrations that have already been detected in environmental samples. During the natural river’s measurements, no significant matrix effects were observed, obtaining a recovery percentage of 109.21% ± 7.08, which suggested that the method was suitable for the fast and straightforward analysis of this contaminant. Finally, the SPR measurements were validated with an HPLC method, which demonstrated no significant difference in terms of precision and accuracy, leading to the conclusion that the biosensor reflects its potential as an alternative analytical tool for the monitoring of chlorophene in aquatic environments.