Due to its chemical properties, glyphosate [N-(phosphonomethyl)glycine] is one of the most commonly used agricultural herbicides globally. Due to risks associated with human exposure to glyphosate and its potential harmfulness, the need to develop specific, accurate, online, and sensitive methods is imperative. In accordance with this, the present review is focused on recent advances in developing nanomaterial-based sensors for glyphosate detection. Reported data from the literature concerning glyphosate detection in the different matrices using analytical methods (mostly chromatographic techniques) are presented; however, they are expensive and time-consuming. In this sense, nanosensors’ potential applications are explained to establish their advantages over traditional glyphosate detection methods. Zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D), and three- dimensional (3D) materials are reviewed, from biomolecules to metallic compounds. Bionanomaterials have generated research interest due to their selectivity with respect to using enzymes, DNA, or antibodies. On the other hand, Quantum Dots also are becoming relevant for their vast surface area and good limit of detection values (in the range of pM). This review presents all the characteristics and potential applications of different nanomaterials for sensor development, bearing in mind the necessity of a glyphosate detection method with high sensitivity, selectivity, and portability.

A spectrophotometric method for the determination of glyphosate based on the monitoring of a complex formation between bis 5-phenyldipyrrinate of nickel (II) and the herbicide was developed. The method showed a short response time (10 s), high selectivity (very low interference from other pesticides and salts), and high sensitivity (LOD 2.07 × 10⁻⁷ mol/L, LOQ 9.87 × 10⁻⁷ mol/L, and a K_d from 1.75 × 10⁻⁶ to 6.95 × 10⁻⁶ mol/L). The Job plot showed that complex formation occurs with a 1:1 stoichiometry. The method was successfully applied in potable, urban, groundwater, and residual-treated water samples, showing high precision (0.34–2.9%) and accuracy (87.20–119.04%). The structure of the complex was elucidated through theoretical studies demonstrating that the nickel in the bis 5-phenyldipyrrinate forms a distorted octahedral molecular geometry by expanding its coordination number through one bond with the nitrogen and another with the oxygen of the glyphosate’ carboxyl group, at distances between 1.89–2.08 Å.

Dapsone (DDS) is an antibacterial drug with well-known antioxidant properties. However, the antioxidant behavior of its derivatives has not been well explored. In the present work, the antioxidant activity of 10 dapsone derivatives 4-substituted was determined by an evaluation in two in vitro models (DPPH radical scavenging assay and ferric reducing antioxidant power). These imine derivatives 1–10 were obtained through condensation between DDS and the corresponding aromatic aldehydes 4-substuited. Three derivatives presented better results than DDS in the determination of DPPH (2, 9, and 10). Likewise, we have three compounds with better reducing activity than dapsone (4, 9, and 10). In order to be more insight, the redox process, a conceptual DFT analysis was carried out. Molecular descriptors such as electronic distribution, the total charge accepting/donating capacity (I/A), and the partial charge accepting/donating capacity (ω⁺/ω⁻) were calculated to analyze the relative donor-acceptor capacity through employing a donor acceptor map (DAM). The DFT calculation allowed us to establish a relationship between GAP_HOMO-LUMO and DAM with the observed antioxidant effects. According to the results, we concluded that compounds 2 and 3 have the lowest R_a values, representing a good antioxidant behavior observed experimentally in DPPH radical capturing. On the other hand, derivatives 4, 9, and 10 display the best reducing capacity activity with the highest ω⁻ and R_d values. Consequently, we propose these compounds as the best antireductants in our DDS imine derivative series.

The appearance of a new coronavirus, SARS-CoV-2, in 2019 kicked off an international public health emergency. Although rapid progress in vaccination has reduced the number of deaths, the development of alternative treatments to overcome the disease is still necessary. It is known that the infection begins with the interaction of the spike glycoprotein (at the virus surface) and the angiotensin-converting enzyme 2 cell receptor (ACE2). Therefore, a straightforward solution for promoting virus inhibition seems to be the search for molecules capable of abolishing such attachment. In this work, we tested 18 triterpene derivatives as potential inhibitors of SARS-CoV-2 against the receptor-binding domain (RBD) of the spike protein by means of molecular docking and molecular dynamics simulations, modeling the RBD S1 subunit from the X-ray structure of the RBD-ACE2 complex (PDB ID: 6M0J). Molecular docking revealed that at least three triterpene derivatives of each type (i.e., oleanolic, moronic and ursolic) present similar interaction energies as the reference molecule, i.e., glycyrrhizic acid. Molecular dynamics suggest that two compounds from oleanolic and ursolic acid, OA5 and UA2, can induce conformational changes capable of disrupting the RBD-ACE2 interaction. Finally, physicochemical and pharmacokinetic properties simulations revealed favorable biological activity as antivirals.