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To fight the flourishment of drug-resistant bacteria caused by antibiotics and the dissemination of antibiotic resistance genes (ARGs), it is of great urgency to develop multifunctional non-antibiotic agents with residual antibiotics elimination, and ARGs dissemination inhibition properties. Herein, sodium dodecyl sulfate (SDS) was modified onto the surface of Fe 2 O 3 @MoS 2 by ultrasonic method to obtain the Z-scheme, multifunctional Fe 2 O 3 @MoS 2 @SDS nanocomposites. The Fe 2 O 3 @MoS 2 @SDS (weight ratio of Fe 2 O 3 @MoS 2 and SDS was 1:1) was selected as the optimal agent. Under NIR irradiation, the Fe 2 O 3 @MoS 2 @SDS had a photothermal conversion efficiency of 45.96%, and could generate plenty of reactive oxygen species (ROS) at the same time. Under the synergy of photothermal and photodynamic, the antibacterial efficiency of Fe 2 O 3 @MoS 2 @SDS to E. coli, MRSA and P. aeruginosa could reach 99.95%, 99.97% and 99.58%, respectively, indicating excellent photothermal-photodynamic therapy (PPT) effect. The Fe 2 O 3 @MoS 2 @SDS also displayed photocatalytic activity in degradation of tetracycline (TC). The degradation rate of TC could reach 92.3% after 2 h of visible light irradiation. The obtained results indicated that a promising Fe 2 O 3 @MoS 2 @SDS composite based multifunctional nanoplatform could be constructed for NIR induced bacterial inactivation, antibiotics degradation and ARGs dissemination inhibition., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Infection caused by antibiotic-resistant bacteria is serious threat for public health, and calls for novel antibacterial agents with versatile functions. In particular, nanomaterial is one of promising candidates to fight the increasing antibiotic resistance crisis. Here, we synthesized distinct Fe 3 O 4 @MoS 2 @SDS nanocomposites by ultrasonication assisted SDS coating on the Fe 3 O 4 @MoS 2 . Photothermal investigation indicated that the Fe 3 O 4 @MoS 2 @SDS showed excellent and stable photothermal performance and could be a NIR-induced photothermal reagent. It also displayed superior disinfection ability of Escherichia coli (E. coli), Methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa (P. aeruginosa) and in vivo wound healing ability with the help of NIR irradiation. According to the results of electron paramagnetic resonance (EPR) and radical capture tests, plenty of superoxide, hydroxyl radicals, singlet oxygen and living cell reactive oxygen species can be observed under NIR irradiation. Besides, the synergistic effect Fe 3 O 4 @MoS 2 @SDS and NIR irradiation eradicated almost all the biofilms of MRSA, so this kind of function enhanced the disinfection ability of Fe 3 O 4 @MoS 2 @SDS under NIR irradiation. Furthermore, its inhibition effect on antibiotic resistance gene dissemination was also investigated. As expected, the Fe 3 O 4 @MoS 2 @SDS could efficiently and broadly block the horizontal transfer of antibiotic resistance genes which mediated by conjugative plasmids, and its blocking effect was better than that we have reported Fe 3 O 4 @MoS 2 . Overall, our findings revealed that the Fe 3 O 4 @MoS 2 @SDS could be a potential candidate for photothermal-photodynamic therapy and antibiotic resistance gene dissemination inhibition., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In this study, we found that Fe 3 O 4 promoted horizontal gene transfer (HGT), but when Fe 3 O 4 was composited with MoS 2 , the Fe 3 O 4 @MoS 2 nanocomposite interacting with bacteria significantly blocked the HGT in the conjugation system. qPCR was used to analyze the expression of genes belonging to the chromosome and plasmid in the conjugation system. Results demonstrated that Fe 3 O 4 @MoS 2 inhibited conjugation by promoting the expression of the global regulatory gene (trbA) and inhibiting the expression of conjugative transfer genes involved in mating pair formation (traF, trbB), DNA replication (trfA), and porins (outer membrane protein (omp) A and ompC). All of these genes are related to the permeability of the cell membrane, except for trfA. The results showed that Fe 3 O 4 @MoS 2 interacted with bacteria to decrease their permeability against exogenous DNA. MoS 2 may play an essential role in the HGT-inhibiting activity of Fe 3 O 4 @MoS 2 . This study highlights the diverse biological properties of nano-materials and provides clues for nano-scientists to develop environmentally friendly materials., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Nanomaterials of Al 2 O 3 and TiO 2 have been proved to promote the spread of antibiotic resistance genes (ARGs) by horizontal gene transfer. In this work, we found that Fe 2 O 3 @MoS 2 nanocomposite inhibited the horizontal gene transfer (HGT) by inhibiting the conjugative transfer mediated by RP4-7 plasmid. To discover the mechanism of Fe 2 O 3 @MoS 2 inhibiting HGT, the bacterial cells were collected under the optimal mating conditions. The collected bacterial cells were used for analyzing the expression levels of genes unique to the plasmid and the bacterial chromosome in the conjugation system by qPCR. The results of genes expression demonstrated that the mechanism of Fe 2 O 3 @MoS 2 inhibited conjugation by promoting the expression of global regulatory gene (trbA) and inhibiting the expression of conjugative transfer genes involved in mating pair formation (traF, trbB) and DNA replication (trfA). The risk assessment of Fe 2 O 3 @MoS 2 showed that it had very low toxicity to organisms. The findings of this paper showed that Fe 2 O 3 @MoS 2 , as an inhibitor of horizontal gene transfer, is an environment-friendly material., (Copyright © 2019 Elsevier Inc. All rights reserved.)