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Metal ions have great significance for agricultural development, food safety, and human health. In turn, there exists an imperative need for the development of novel, sensitive, and reliable sensing techniques for various metal ions. Agricultural sensors for the diagnosis of both agricultural safety and nutritional health can establish quality and safety traceability systems of both agro-products and food to guarantee human health, even life safety. Metal-organic frameworks (MOFs) are utilized widely for the design of diversified sensors due to their distinctive structural characteristics and extraordinary optical and electrical properties. To serve agricultural sensors better, this review is dedicated to providing a brief overview of the synthesis of MOFs, the modification of MOFs, the fabrication of MOF-based film electrodes, the applications of MOF-based agricultural sensors for metal ions, which are centered on electrochemical sensors and optical sensors, and current challenges of MOF-based agricultural sensors. In addition, this review also provides potential future opportunities for the development and practical application of agricultural sensors., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Four new ruthenium polypyridyl complexes with prenyl groups, [Ru(bpy) 2 (MHIP)](PF 6 ) 2 (Ru(II)-1), [Ru(dtb) 2 (MHIP)](PF 6 ) 2 (Ru(II)-2), [Ru(dmb) 2 (MHIP)](PF 6 ) 2 (Ru(II)-3), and [Ru(dmob) 2 (MHIP)](PF 6 ) 2 (Ru(II)-4) (bpy = 2,2'-bipyridine, dtb = 4,4'-di-tert-butyl-2,2'-bipyridine, dmb = 4,4'-dimethyl-2,2'-bipyridine, dmob = 4,4'-dimethoxy-2,2'-bipyridine, and MHIP = 2-(2,6-dimethylhepta-1,5-dien-1-yl)-1H-imidazo[4,f][1,10]phenanthroline), were synthesized and characterized. Their antibacterial activities against Staphylococcus aureus were assessed, and the minimum inhibition concentration (MIC) value of Ru(II)-2 against S. aureus was only 0.5 µg/mL, showing the best antibacterial activity among them. S. aureus could be quickly killed by Ru(II)-2 in 30 min and Ru(II)-2 displayed an obvious inhibitive effect on the formation of a biofilm, which was essential to avoid the development of drug-resistance. Meanwhile, Ru(II)-2 exhibited a stable MIC value against antibiotic-resistant bacteria. The antibacterial mechanism of Ru(II)-2 was probably related to depolarization of the cell membrane, and a change of permeability was associated with the formation of reactive oxygen species, leading to leakage of nucleic acid and bacterial death. Furthermore, Ru(II)-2 hardly showed toxicity to mammalian cells and the Galleria mellonella worm. Finally, murine infection studies also illustrated that Ru(II)-2 was highly effective against S. aureus in vivo., (© 2023 Deutsche Pharmazeutische Gesellschaft.)

The mutant KRAS was considered as an "undruggable" target for decades, especially KRAS G12D . It is a great challenge to develop the inhibitors for KRAS G12D which lacks the thiol group for covalently binding ligands. The discovery of MRTX1133 solved the dilemma. Interestingly, MRTX1133 can bind to both the inactive and active states of KRAS G12D . The binding mechanism of MRTX1133 with KRAS G12D , especially how MRTX1133 could bind the active state KRAS G12D without triggering the active function of KRAS G12D , has not been fully understood. Here, we used a combination of all-atom molecular dynamics simulations and Markov state model (MSM) to understand the inhibition mechanism of MRTX1133 and its analogs. The stationary probabilities derived from MSM show that MRTX1133 and its analogs can stabilize the inactive or active states of KRAS G12D into different conformations. More remarkably, by scrutinizing the conformational differences, MRTX1133 and its analogs were hydrogen bonded to Gly60 to stabilize the switch II region and left switch I region in a dynamically inactive conformation, thus achieving an inhibitory effect. Our simulation and analysis provide detailed inhibition mechanism of KRAS G12D induced by MRTX1133 and its analogs. This study will provide guidance for future design of novel small molecule inhibitors of KRAS G12D ., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Three new Ru(ii) complexes, [Ru(dtb) 2 PPAD](PF 6 ) 2 ( Ru-1 ), [Ru(dmob) 2 PPAD](PF 6 ) 2 ( Ru-2 ) and [Ru(bpy) 2 PPAD](PF 6 ) 2 ( Ru-3 ) (dtb = 4,4'-di -tert -butyl-2,2'-bipyridine, dmob = 4,4'-dimethyl-2,2'-bipyridine, bpy = 2,2'-bipyridine and PPAD = 2-(pyridine-3-yl)-1 H -imidazo[4,5 f ][1.10]phenanthracene-9,10-dione), were synthesized and characterized by 1 H NMR and 13 C NMR spectroscopy, HRMS and HPLC. Among them, Ru-1 showed excellent antimicrobial activity against Gram-positive bacteria Staphylococcus aureus (minimum inhibitory concentration (MIC) = 1 μg mL -1 ) and low hemolytic and cytotoxic activity. In addition, Ru-1 showed obviously rapid bactericidal activity, low resistance rate, bacterial biofilm destroying activity and high biosafety in vivo . Moreover, skin infection models and a mouse model of sepsis indicated that the anti-infective efficacy of Ru-1 was comparable to that of vancomycin. Mechanism exploration results showed that the antibacterial behavior is probably related with targeting of the bacterial cell membrane and inhibiting topoisomerase I., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Due to the emergence and wide spread of methicillin-resistant Staphylococcus aureus , the treatment of this kind of infection becomes more and more difficult. To solve the problem of drug resistance, it is urgent to develop new antibiotics to avoid the most serious situation of no drug available. Three new Ru complexes [Ru (dmob) 2 PMA] (PF6) 2 ( Ru-1 ) [Ru (bpy) 2 PMA] (PF6) 2 ( Ru-2 ) and [Ru (dmb) 2 PMA] (PF6) 2 ( Ru-3 ) (dmob = 4,4'-dimethoxy-2,2'-bipyridine, bpy = 2,2'-bipyridine, dmb = 4,4'-dimethyl-2,2'-bipyridine and PMA = N-(4-(1H-imidazo [4,5-f] [1,10] phenanthrolin-2-yl) -4-methyl-N-(p-tolyl) aniline) were synthesized and characterized by 1H NMR, 13C NMR and HRMS. The detailed molecular structure of Ru-3 was determined by single crystal X-ray diffraction. Their antibacterial activities against Staphylococcus aureus ( Staphylococcus aureus ) were obvious and Ru-3 showed the best antibacterial effect with the minimum inhibitory concentration value of 4 μg ml -1 . Therefore, further study on its biological activity showed that Ru-3 can effectively inhibit the formation of biofilm and destroy cell membrane. In vitro hemolysis test showed that Ru-3 has almost negligible cytotoxicity to mammalian red blood cells. In the toxicity test of wax moth insect model, Ru-3 exhibited low toxicity in vivo . These results, combined with histopathological studies, strongly suggest that Ru-3 was almost non-toxic. In addition, the synergistic effect of Ru-3 with common antibiotics such as ampicillin, chloramphenicol, tetracycline, kanamycin and gentamicin on Staphylococcus aureus was detected by chessboard method. Finally, in vivo results revealed that Ru-3 could obviously promote the wound healing of Staphylococcus aureus infected mice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jiang, Ma, Xiong, Tan, Duan, Liao and Wang.)

Herein, Ti 3 C 2 T x MXene/N-doped reduced graphene oxide (MXene/N-rGO) composite was employed as the electrocatalyst to construct a new electrochemical sensing platform for the determination of adrenaline (AD). The MXene/N-rGO was synthesized via a facile one-step hydrothermal method, where ethylenediamine acted as a reducing agent and N source. The doped N in rGO served as a bridge between MXene and rGO through tight hydrogen bonds. Scanning electron microscopy showed that large numbers of MXenes with accordion-like morphology were distributed on the surface of the N-rGO. The MXene/N-rGO composite displayed a synergetic catalytic effect for oxidizing AD, originating from the unique catalytic activity of N-rGO and the large surface area and satisfactory conductivity of MXene. These characteristics of composite material led to a remarkable effect on signal amplification for the detection of AD, with a wide linear range from 10.0 nM to 90.0 μ M and a low detection limit of 3.0 nM based on a signal to noise ratio of 3. Moreover, the MXene/N-rGO electrode displayed good stability, repeatability, and reproducibility. Additionally, the proposed sensor was successfully applied for voltammetric sensing of AD in urine with recoveries from 97.75% to 103.0%., (© 2021 IOP Publishing Ltd.)