The diagnosis of respiratory viruses of zoonotic origin (RVsZO) such as influenza and coronaviruses in humans is crucial, because their spread and pandemic threat are the highest. Surface–enhanced Raman spectroscopy (SERS) is an analytical technique with promising impact for the point–of–care diagnosis of viruses. It has been applied to a variety of influenza A virus subtypes, such as the H1N1 and the novel coronavirus SARS−CoV−2. In this work, a review of the strategies used for the detection of RVsZO by SERS is presented. In addition, relevant information about the SERS technique, anthropozoonosis, and RVsZO is provided for a better understanding of the theme. The direct identification is based on trapping the viruses within the interstices of plasmonic nanoparticles and recording the SERS signal from gene fragments or membrane proteins. Quantitative mono- and multiplexed assays have been achieved following an indirect format through a SERS-based sandwich immunoassay. Based on this review, the development of multiplex assays that incorporate the detection of RVsZO together with their specific biomarkers and/or secondary disease biomarkers resulting from the infection progress would be desirable. These configurations could be used as a double confirmation or to evaluate the health condition of the patient.

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A graphite‐epoxy electrode (GE) modified with multiwalled carbon nanotubes (MWCNTs) and horseradish peroxidase (GE/MWCNTs‐HRP) was used to build a glyphosate biosensor whose performance in aqueous solutions depends on the enzyme activity. For the biosensor preparation, MWCNTs were deposited onto the GE surface by electrophoresis using an oxidative treatment (H2SO4/HNO3) in presence of cetyl tributylammonium bromide (CTAB) as a cationic surfactant. The surfactant was further removed from the MWCNTs surface by dipping the electrode in an EtOH/HCl solution. The physical immobilization of HRP and therefore the glyphosate sensing capabilities was tested at pH 4 where the herbicide exhibits one only species. Circular dichroism studies suggested that the secondary structure of HRP changes as a result of its interaction with glyphosate and that this change is intensified by the combination of glyphosate and H2O2, which may explain the decrease of the enzyme catalytic activity with the increase of glyphosate concentration. The glyphosate quantification in doped‐maize kernels was highly reproducible and exhibits detection and quantification limits of 1.32 pM and 1.63 pM respectively. The biosensor is also characterized by a high recovery (100 %) and precision (coefficient of variation <1 %) and can be employed in presence of interfering substances such as chlorpyrifos (an organophosphate pesticide) and starch.

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