Concerns arising from accidental and occasional releases of novel industrial nanomaterials to the environment and waterbodies are rapidly increasing as the production and utilization levels of nanomaterials increase every day. In particular, two-dimensional nanosheets are one of the most significant emerging classes of nanomaterials used or considered for use in numerous applications and devices. This study deals with the interactions between 2D molybdenum disulfide (MoS₂) nanosheets and beneficial soil bacteria. It was found that the log-reduction in the survival of Gram-positive Bacillus cereus was 2.8 (99.83%) and 4.9 (99.9988%) upon exposure to 16.0 mg/mL bulk MoS₂ (macroscale) and 2D MoS₂ nanosheets (nanoscale), respectively. For the case of Gram-negative Pseudomonas aeruginosa, the log-reduction values in bacterial survival were 1.9 (98.60%) and 5.4 (99.9996%) for the same concentration of bulk MoS₂ and MoS₂ nanosheets, respectively. Based on these findings, it is important to consider the potential toxicity of MoS₂ nanosheets on beneficial soil bacteria responsible for nitrate reduction and nitrogen fixation, soil formation, decomposition of dead and decayed natural materials, and transformation of toxic compounds into nontoxic compounds to adequately assess the environmental impact of 2D nanosheets and nanomaterials.

The growing prevalence of antimicrobial resistance in bacterial strains has increased the demand for preventing biological deterioration on the surfaces of films used in applications involving food contact materials (FCMs). Herein, we prepared superhydrophobic film surfaces using a casting process that involved the combination of low-density polyethylene (LDPE) with solutions containing surface energy-reducing silica (SRS). The bacterial antifouling properties of the modified film surfaces were evaluated using Escherichia coli O157:H7 and Staphylococcus epidermidis via the dip-inoculation technique. The reduction in bacterial populations on the LDPE film embedded with SRS was confirmed to be more than 2 log-units, which equates to over 99%, when compared to the bare LDPE film. Additionally, the modified film demonstrated liquid-repelling properties against food-related contaminants, such as blood, beverages, and sauces. Moreover, the modified film demonstrated enhanced durability and robustness compared to one of the prevalent industry methods, dip-coating. We anticipate that the developed LDPE/nano-silica composite film represents a promising advancement in the multidisciplinary aspects of food hygiene and safety within the food industry, particularly concerning FCMs.

Herein, we describe interfacially-assembled [7]helicene films that were deposited on graphene monolayer using the Langmuir-Schaefer deposition by utilizing the interactions of nonplanar (helicene) and planar (graphene) π–π interactions as functional antifouling coatings. Bacterial adhesion of Staphylococcus aureus on helicene—graphene films was noticeably lower than that on bare graphene, up to 96.8% reductions in bacterial adhesion. The promising bacterial antifouling characteristics of helicene films was attributed to the unique molecular geometry of helicene, i.e., nano-helix, which can hinder the nanoscale bacterial docking processes on a surface. We envision that helicene—graphene films may eventually be used as protective coatings against bacterial antifouling on the electronic components of clinical and biomedical devices.

The limited water solubility and environmental instability of natural pesticidal compounds impede their broader agricultural use. This study reports an amphiphile-assisted nanoprecipitation method to imbibe azadirachtin-rich neem seed extract (NSE) within a glycine carrier matrix, yielding a stable nanocomposite biopesticide. The formulation, prepared using polyoxyethylene sorbitan monooleate as a stabilizer and glycine as the matrix former, followed by lyophilization, exhibited a hydrodynamic diameter of ∼8 nm when redispersed in water. This glycine nanopesticide (GNP) significantly improved the photostability of azadirachtin under UV-AB irradiation (2000 μW/cm²); spectrophotometric analysis revealed a 27.7% reduction in photodegradation over a 4 day period compared to unformulated NSE powder demonstrated dialysis-based in vitro release assay showed sustained release, with 68.2 ± 2.1% released over 7 days, fitting an exponential model with a time constant of 37.6 h. Contact bioassays against Spodoptera frugiperda larvae revealed enhanced larvicidal potency. LC₅₀ values showed a 1.5- to 6.6-fold improvement compared to unformulated NSE over 11 days. On day 7, GNP had an LC₅₀ of 0.13 mg/mL, compared to 0.86 mg/mL for NSE powder. The nanoformulation also improved wettability on tomato leaves, reducing the contact angle from 99.0° ± 1.6° (DI water) to ∼60° at a concentration of 100 mg/mL GNP. This approach offers a practical method for improving the stability, delivery, and efficacy of hydrophobic biopesticides.