Safety Procedures to Work with West Nile Virus in Biosafety Level 3 Facilities

West Nile virus (WNV) can cause severe and sometimes fatal disease, but we do not have treatments or therapeutics to manage these outcomes. Since its introduction to the USA in 1999, WNV has been handled in a biosafety level 3 laboratory to decrease risk to researchers, requiring strict safety protocols and important considerations with planning experiments. Recent changes in US guidelines suggest that WNV can be handled at a lower biosafety level due to its endemicity in the USA and generally minor symptoms, but some research still requires the use of the agent at biosafety level 3. This chapter will briefly discuss the considerations of biosafety when working with WNV.

Motivating Proactive Biorisk Management

Scholars and practitioners of biosafety and biosecurity (collectively, biorisk management or BRM) have argued that life scientists should play a more proactive role in monitoring their work for potential risks, mitigating harm, and seeking help as necessary. However, most efforts to promote proactive BRM have focused on training life scientists in technical skills and have largely ignored the extent to which life scientists wish to use them (ie, their motivation). In this article, we argue that efforts to promote proactive BRM would benefit from a greater focus on life scientists' motivation. We review relevant literature on life scientists' motivation to practice BRM, offer examples of successful interventions from adjacent fields, and outline ideas for possible interventions to promote proactive BRM, along with strategies for iterative development, testing, and scaling.

The current emergence of monkeypox: The recurrence of another smallpox?

Since its first confirmation in London on 12 May 2022, many monkeypox cases have been reported worldwide. Noticeably, the epidemiology, pathology, and clinical features of the current emergence have been compared to those of smallpox, a severe contagious disease historically epidemic worldwide for nearly 3,000 years. However, some characteristics of the present outbreak differed from those of previous monkeypox outbreaks. Herein, we ask if this emergence of monkeypox could cause another global pandemic similar to smallpox or influenza or if it is only the re-emergence of a new strain. To address these questions, we reviewed its virology, transmission, clinical characteristics, experimental diagnosis, and prevention and intervention, giving our commentary along the way.

Multicomponent biodegradable hydrogels based on natural biopolymers as environmentally coating membrane for slow-release fertilizers: Effect of crosslinker type

This work aims to explore the suitable crosslinker type for synthesizing multicomponent biodegradable hydrogels of cassava starch (CSt) grafted with acrylic acid (AA) semi-interpenetrated by natural rubber (NR)/polyvinyl alcohol (PVA) blend (CSt-g-PAA/NR/PVA, CSB semi-IPN hydrogel) as coating membranes for slow-release urea fertilizers. Three crosslinker types (ethylene glycol dimethacrylate (EGDMA), glutaraldehyde (GA) and N,N'- methylene-bis-acrylamide (MBA)) were employed to investigate their influences on the properties of CSB semi-IPN hydrogels. The results revealed that the different crosslinkers clearly exhibited different water-retention capacity, biodegradation, slow release and plant growth performance of the CSB semi-IPN hydrogels. The CSB-G2 hydrogel (crosslinked with GA at 2 wt%) remained higher water-retention at 30 days (20.2 %), greater rate of degradation (1.37 %/day) and better biosafety (OD600 = 2.26) compared to CSB-M2 and CSB-E2 hydrogels. After urea pellets were coated by CSB hydrogels and wax layers (UCSBw formulation), the urea release rates from the UCSBw-M2, UCSBw-E2 and UCSBw-G2 formulations in 30 days were 67.7 %, 68.7 % and 78.3 %, respectively, corresponding well with swelling ratio and pore size. Besides, the UCSBw-G2 formulation yielded the greater plant growth performance (height, leaf length and product weight) than other two formulations and commercial fertilizer. In conclusion, GA is the suitable crosslinker for synthesizing the CSB-g-PAA/NR/PVA hydrogels with high water-retention, excellent biodegradation, less negative impact on environments, acceptable slow-release rate, good biosafety and reasonable price for slow-release fertilizers.

Advances in nanotechnology application in biosafety materials: A crucial response to COVID-19 pandemic

The outbreak of coronavirus disease 2019 (COVID-19) has adversely affected the public domain causing unprecedented cases and high mortality across the globe. This has brought back the concept of biosafety into the spotlight to solve biosafety problems in developing diagnostics and therapeutics to treat COVID-19. The advances in nanotechnology and material science in combination with medicinal chemistry have provided a new perspective to overcome this crisis. Herein, we discuss the efforts of researchers in the field of material science in developing personal protective equipment (PPE), detection devices, vaccines, drug delivery systems, and medical equipment. Such a synergistic approach of disciplines can strengthen the research to develop biosafety products in solving biosafety problems.

Bioactivity of Deverra tortuosa essential oil, its nanoemulsion, and phenylpropanoids against the cowpea weevil, a stored grain pest with eco-toxicological evaluations

The essential oil (EO) was hydrodistilled from of Deverra tortuosa aerial parts. Fifty-six components amounting 99.3% were identified in EO through using gas chromatography-flame ionization detection (GC-FID) and (GC-MS). Phenylpropanoids, dillapiole (41.6%), elemicin (7.3%) and myristicin (5.1%), and the monoterpene, sabinene (4.2%) were identified as the major terpenes. An oil-in-water nanoemulsion (particle size 70.3 nm) was developed from EO adopting a low-energy method. The EO products showed insecticidal and biochemical effects against the cowpea weevil Callosobruchus maculatus. Based on a 48-h exposure period, the oil nanoemulsion exhibited a superior contact bioactivity (LC₅₀ = 10.3 µg/cm²), followed by EO (LC₅₀ = 23.1 µg/cm²), dillapiole (LC₅₀ = 27.8 µg/cm²), and myristicin (LC₅₀ = 37.1 µg/cm²). Upon fumigation, nanoemulsion and EO were superior as fumigants (LC₅₀ after 48 h were 6.9 and 14.3 µl/l, respectively). Test materials showed a residual bioactivity against C. maculatus, where EO, dillapiole, and myristicin showed the strongest grain protecting activity. EO products significantly inhibited acetylcholinesterase (AChE) activity of C. maculatus adults. Test products were safe toward the non-target earthworms and did not alter the viability of cowpea seeds. There are evidences for the potential of using EO of D. tortuosa and its nanoemulsion and phenylpropanoids as natural grain protectants against C. maculatus.

Interactive effects of cerium and copper to tune the microstructure of silicocarnotite bioceramics towards enhanced bioactivity and good biosafety

Endowing biomaterials with functional elements enhances their biological properties effectively. However, improving bioactivity and biosafety simultaneously is still highly desirable. Herein, cerium (Ce) and copper (Cu) are incorporated into silicocarnotite (CPS) to modulate the constitution and microstructure for degradability, bioactivity and biosafety regulation. Our results demonstrated that introducing Ce suppressed scaffold degradation, while, co-incorporation of both Ce and Cu accelerated degradability. Osteogenic effect of CPS in vitro was promoted by Ce and optimized by Cu, and Ce-induced angiogenic inhibition could be mitigated by cell coculture method and reversed by Ce-Cu co-incorporation. Ce enhanced osteogenic and angiogenic properties of CPS in a dose-dependent manner in vivo, and Cu-Ce coexistence exhibited optimal bioactivity and satisfactory biosafety. This work demonstrated that coculture in vitro was more appropriately reflecting the behavior of implanted biomaterials in vivo. Interactive effects of multi-metal elements were promising to enhance bioactivity and biosafety concurrently. The present work provided a promising biomaterial for bone repair and regeneration, and offered a comprehensive strategy to design new biomaterials which aimed at adjustable degradation behavior, and enhanced bioactivity and biosafety.

No adverse dietary effect of a cisgenic fire blight resistant apple line on the non-target arthropods Drosophila melanogaster and Folsomia candida

Genetic modification of apple cultivars through cisgenesis can introduce traits, such as disease resistance from wild relatives, quickly and without crossing. This approach was used to generate the cisgenic apple line C44.4.146, a 'Gala Galaxy' carrying the fire blight resistance gene FB_MR5. In contrast to traditionally bred apple cultivars, genetically modified (GM) plants need to undergo a regulatory risk assessment considering unintended effects before approval for commercial release. To determine potential unintended effects of C44.4.146, we assessed major leaf components and effects on the fitness of the decomposers Drosophila melanogaster (fruit fly) and Folsomia candida (collembolan), which were fed a diet amended with powdered apple leaf material. Leaf material of 'Gala Galaxy', several natural 'Gala' mutants, and the unrelated apple cultivar 'Ladina' were used for comparison. The genetic modification did not alter major leaf components and did not adversely affect survival, growth, or fecundity of the two decomposers. Consistent with previous studies with other GM crops, the differences between conventionally bred cultivars were greater than between the GM line and its non-GM wild type. These data provide a baseline for future risk assessments.

Risk assessment of RNAi-based pesticides to non-target organisms: Evaluating the effects of sequence similarity in the parasitoid wasp Telenomus podisi

RNA interference (RNAi)-based pesticides are promising novel pest management products that might reduce environmental impacts compared to other pesticides. Their sequence-guided mode of action facilitates a high species-selectivity, preventing harm on non-target organisms. However, there is currently no consensus on the minimum needed sequence similarity for efficient RNAi in insects and studies have shown that adverse effects in non-targets cannot always be ruled out a priori. This study investigates the effects of exposing the parasitoid wasp Telenomus podisi to double-stranded RNA (dsRNA) which is lethal to its host, the Neotropical brown stink bug Euschistus heros. Feeding T. podisi with wasp-specific dsRNA targeting the vATPase A and actin-2 genes led to 76.4 ± 9.9% and 76.7 ± 8.8% mortality respectively, demonstrating that dietary RNAi is functional in T. podisi. When feeding T. podisi with E. heros-specific dsRNA targeting the same genes, no lethal or sublethal effects were observed. To link sequence similarity to potential gene silencing effects in the parasitoids, the expression of genes showing the highest degree of similarity (17-21 nucleotide matches) with these two target genes was monitored and was found unaffected by the E. heros-specific dsRNA. Our study confirms that RNAi was in this case highly specific and that for E. heros, RNAi-based pesticides can be used complementary to biological control in an integrated pest management context.

Multifunctional effects of wound dressing based on chitosan-coordinated argentum with resistant bacterial penetration

Third-degree scald, causing serious tissue destruction with continuous pain, easily leads to microbial infections and delayed wound healing. Therefore, a multifunctional treatment is attractive for seriously damaged tissue. Herein, carboxymethyl chitosan-coordinated argentum (Ag-CMC) was synthesized via a complexation method, and then the Ag⁺ release, antibacterial activity, biocompatibility, pain relief and wound healing properties of Ag-CMC were investigated in vitro and in vivo. The results revealed that Ag⁺ had interacted with carboxymethyl chitosan, containing approximately 1.2% of silver. The Ag-CMC (50-200 μg/mL) with Ag⁺ sustained release exhibited significant antibacterial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, drug-resistant E. coli, PA, MRSA and good biocompatibility with L929 cells. Furthermore, antibacterial and wound healing experiments demonstrated that Ag-CMC achieved an effective contraction rate of 90% after 28 days by accelerating re-epithelialization, regulating inflammation response, relieving pain and infections. Therefore, Ag-CMC is a safe multifunctional treatment for wound healing and infections.

Gain-of-function research

The term Gain-of-Function (GoF) describes the gain of new functions by organisms through genetic changes, which can naturally occur or by experimental genetic modifications. Gain-of-Function research on viruses is enhancing transmissibility, virus replication, virulence, host range, immune evasion or drug and vaccine resistance to get insights into the viral mechanisms, to create and analyze animal models, to accelerate drug and vaccine development and to improve pandemic preparedness. A subset is the GoF research of concern (GOFROC) on enhanced potentially pandemic pathogens (ePPPs) that could be harmful for humans. A related issue is the military use of research as dual-use research of concern (DURC). Influenza and coronaviruses are main research targets, because they cause pandemics by airborne infections. Two studies on avian influenza viruses initiated a global debate and a temporary GoF pause in the United States which ended with a new regulatory framework in 2017. In the European Union and China, GoF and DURC are mainly covered by the legislation for laboratory safety and genetically modified organisms. After the coronavirus outbreaks, the GoF research made significant advances, including analyses of modified MERS-like and SARS-like viruses and the creation of synthetic SARS-CoV-2 viruses as a platform to generate mutations. The GoF research on viruses will still play an important role in future, but the need to clarify the differences and overlaps between GoF research, GOFROC and DURC and the need for specialized oversight authorities are still debated.

Highly efficient magnetic ablation and the contrast of various imaging using biocompatible liquid-metal gallium

Background

Although the powerful clinical effects of radiofrequency and microwave ablation have been established, such ablation is associated with several limitations, including a small ablation size, a long ablation time, the few treatment positioning, and biosafety risks. To overcome these limitations, biosafe and efficient magnetic ablation was achieved in this study by using biocompatible liquid gallium as an ablation medium and a contrast medium for imaging.

Results

Magnetic fields with a frequency (f) lower than 200 kHz and an amplitude (H) × f value lower than 5.0 × 10⁹ Am⁻¹ s⁻¹ were generated using the proposed method. These fields could generate an ablation size of 3 cm in rat liver lobes under a temperature of approximately 300 °C and a time of 20 s. The results of this study indicate that biomedical gallium can be used as a contrast medium for the positioning of gallium injections and the evaluation of ablated tissue around a target site. Liquid gallium can be used as an ablation medium and imaging contrast medium because of its stable retention in normal tissue for at least 3 days. Besides, the high anticancer potential of gallium ions was inferred from the self-degradation of 100 µL of liquid gallium after around 21 days of immersion in acidic solutions.

Conclusions

The rapid wireless ablation of large or multiple lesions was achieved through the simple multi-injection of liquid gallium. This approach can replace the currently favoured procedure involving the use of multiple ablation probes, which is associated with limited benefits and several side effects.

Methods

Magnetic ablation was confirmed to be highly efficient by the consistent results obtained in the simulation and in vitro tests of gallium and iron oxide as well as the electromagnetic specifics and thermotherapy performance comparison detailed in this study Ultrasound imaging, X-ray imaging, and magnetic resonance imaging were found to be compatible with the proposed magnetic ablation method. Self-degradation analysis was conducted by mixing liquid gallium in acidic solutions with a pH of approximately 5–7 (to imitate a tumour-containing microenvironment). X-ray diffraction was used to identify the gallium oxides produced by degraded gallium ions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12938-022-01003-9.

Nanomaterial-Augmented Formulation of Disinfectants and Antiseptics in Controlling SARS CoV-2

The worldwide COVID-19 pandemic has brought significant consideration toward innovative strategies for overcoming the viral spread. Nanotechnology will change our lives in several forms as its uses span from electronics to pharmaceutical procedures. The use of nanoparticles provides a possibility to promote new antiviral treatments with a low possibility of increasing drug resistance compared to typical chemical-based antiviral treatments. Since the long-term usage of disinfectants and antiseptics at high concentrations has deleterious impacts on well-being and the environment, this review was intended to discuss the antiviral activity of disinfectants and antiseptics required for their activity against respiratory viruses especially SARS-CoV-2. It could improve the inhibition of viral penetration into cells, solvation of the lipid bilayer envelope, and ROS production, therefore enhancing the effect of disinfectants. However, significant concerns about nanomaterial's hazardous effects on individuals and the environment are increasing as nanotechnology flourishes. In this review, we first discuss the significant and essential types of nanomaterials, especially silver and copper, that could be used as antiviral agents and their viral entry mechanisms into host cells. Further, we consider the toxicity on health, and environmental concerns of nanoparticles. Eventually, we present our outlook on the fate of nanomaterials toward viral diseases.

Perturbation of autophagy: An intrinsic toxicity mechanism of nanoparticles

Nanoparticles (NPs) have been widely used for various purposes due to their unique physicochemical properties. Such widespread applications greatly increase the possibility of human exposure to NPs in various ways. Once entering the human body, NPs may interfere with cellular homeostasis and thus affect the physiological system. As a result, it is necessary to evaluate the potential disturbance of NPs to multiple cell functions, including autophagy. Autophagy is an important cell function to maintain cellular homeostasis, and minimizing the disturbance caused by NP exposures to autophagy is critical to nanosafety. Herein, we summarized the recent research progress in nanotoxicity with particular focuses on the perturbation of NPs to cell autophagy. The basic processes of autophagy and complex relationships between autophagy and major human diseases were further discussed to emphasize the importance of keeping autophagy under control. Moreover, the most recent advances on perturbation of different types of NPs to autophagy were also reviewed. Last but not least, we also discussed major research challenges and potential coping strategies and proposed a safe-by-design strategy towards safer applications of NPs.

Working Safely with African Swine Fever Virus

Risk assessment is the cornerstone of working safely with biological agents. The World Health Organization (WHO) Laboratory Biosafety Manual Fourth Edition Monograph on Risk Assessment provides stepwise guidance for carrying out a risk assessment, from gathering information and identifying hazards to evaluating the risks and developing and implementing controls and review.To support the development of a mature safety culture within laboratories, it is important that all staff who handle biological agents understand the process of risk assessment and receive training in identifying hazards and mitigating risk. All personnel can partake in risk assessments, and the guidance is written in such a way that it is applicable to all-not just to biosafety professionals, laboratory scientists, or facility managers.Here we take the guidance from WHO and apply the principles of risk assessment to working with ASFV, illustrating the process using an example activity-the passage of low titer ASFV in cell culture. We discuss other techniques and protocols that you may need to consider when working with ASFV.

Designing, structural determination, and antibacterial activity of injectable ciprofloxacin-loaded gelatin-sodium carboxymethyl cellulose composite nanogels against Staphylococcus aureus

BACKGROUND

The development of nanogels has become an attractive strategy to enhance the antibacterial activity performance of bacteria.

METHODS

The ciprofloxacin composite nanogels were successfully prepared by electrostatic interaction between gelatin (positive charge) and CMC (negative charge) with the help of sodium tripolyphosphate (TPP) as ionic crosslinkers, to increase the antibacterial activity of ciprofloxacin against Staphylococcus aureus (S. aureus) mastitis infection. The formulation screening, characterization, in vitro release, antibacterial activity, and biosafety were studied.

RESULTS

The optimized formulation was fabricated of 20 mg/mL (CMC) and 50 mg/mL (gelatin). The optimized ciprofloxacin composite nanogels were homogenous canary yellow suspension with a sedimentation rate of 1 and were incorporated in nano-sized cross-linked polymeric networks. The particle size distributions of 402.7±1.3 nm, PDI of 0.12±0.01, ZP of -24.5±0.2 mv, EE of 74.28%±0.03%, LC of 20.5%±0.05%. Scanning electron microscope images revealed that ciprofloxacin might be incorporated in nano-sized cross-linked polymeric networks. Fourier transform infrared showed that the spontaneous electrostatic interactions between CMC and gelatin produce the network structure and form the composite nanogels. Meanwhile, in vitro release study showed that ciprofloxacin composite nanogels had sustained-release performances. The ciprofloxacin composite nanogels had more excellent antibacterial activity against SCV 102 isolate than S. aureus ATCC 29213 and S. aureus 101 isolates. The biosafety studies suggested the great promise of the injectable ciprofloxacin composite nanogels as a biocompatible breast injection.

CONCLUSION

This study will afford a potential approach for developing injectable ciprofloxacin-loaded gelatin-CMC composite nanogels for cow S. aureus mastitis therapy.

Assessment of biosafety and implantation feasibility of novel phakic refractive lens

Purpose

We investigated the biosafety and implantation feasibility of a new phakic refractive lens (PRL) in rabbit eyes.

Methods

Short PRLs (S-PRLs), large PRLs (L-PRLs), and large-grooved PRLs (LG-PRLs), were prepared by molding medical-grade liquid silicon. The cytotoxicity and cellular adhesion of the PRLs was assessed in vitro. To assess implantation feasibility, the S-PRL, L-PRL, and LG-PRL were implanted in the posterior chamber of rabbit eyes and the relative position was assessed by optical coherence tomography. The intraocular pressures (IOP) were compared between the S-PRL, L-PRL, LG-PRL, and control groups to evaluate the PRL biosafety after implantation.

Results

The in vitro assays showed that cell viability and cellular adhesion in the S-PRL, L-PRL and LG-PRL groups was not significantly different to those in the control group throughout the study. After implantation into the posterior chamber of rabbit eyes, there were no obvious signs of inflammation or increases in IOP at each time point relative to the control group, demonstrating good biosafety of the PRL. The relative positions of the L-PRLs and LG-PRLs in the posterior chamber were appropriate and the retention frequencies were high.

Conclusions

The newly developed LG-PRL showed good biosafety with negligible in vitro cytotoxicity, ocular inflammation, or fluctuations in IOP. The LG-PRL provided the best implantation feasibility. The grooves on the LG-PRL provided channels for aqueous humor circulation. The LG-PRL is a promising type of PRL with an appropriate size and surface structure for effective correction of refractive errors in rabbit eyes.

Roadmap for Managing SARS-CoV-2 and Other Viruses in the Water Environment for Public Health

The water sector needs to address viral-related public health issues, because water is a virus carrier, which not only spreads viruses (e.g., via drinking water), but also provides information about the circulation of viruses in the community (e.g., via sewage). It has been widely reported that waterborne viral pathogens are abundant, diverse, complex, and threatening the public health in both developed and developing countries. Meanwhile, there is great potential for viral monitoring that can indicate biosafety, treatment performance and community health. New developments in technology have been rising to meet the emerging challenges over the past decades. Under the current coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the world's attention is directed to the urgent need to tackle the most challenging public health issues related to waterborne viruses. Based on critical analysis of the water viral knowledge progresses and gaps, this article offers a roadmap for managing COVID-19 and other viruses in the water environments for ensuring public health.

Oncolytic Activity of Wild-type Newcastle Disease Virus HK84 Against Hepatocellular Carcinoma Associated with Activation of Type I Interferon Signaling

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is listed as one of the most common causes of cancer-related death. Oncolytic therapy has become a promising treatment because of novel immunotherapies and gene editing technology, but biosafety concerns remain the biggest limitation for clinical application. We studied the the antitumor activity and biosafety of the wild-type Newcastle disease virus HK84 strain (NDV/HK84) and 10 other NDV strains.

METHODS

Cell proliferation and apoptosis were determined by cell counting Kit-8 and fluorescein isothiocyanate Annexin V apoptosis assays. Colony formation, wound healing, and a xenograft mouse model were used to evaluate in vivo and in vitro oncolytic effectiveness. The safety of NDV/HK84 was tested in nude mice by an in vivo luciferase imaging system. The replication kinetics of NDV/HK84 in normal tissues and tumors were evaluated by infectious-dose assays in eggs. RNA sequencing analysis was performed to explore NDV/HK84 activity and was validated by quantitative real-time PCR.

RESULTS

The cell counting Kit-8 assays of viability found that the oncolytic activity of the NDV strains differed with the multiplicity of infection (MOI). At an MOI of 20, the oncolytic activity of all NDV strains except the DK/JX/21358/08 strain was >80%. The oncolytic activities of the NDV/HK84 and DK/JX/8224/04 strains were >80% at both MOI=20 and MOI=2. Only NDV/HK84 had >80% oncolytic activities at both MOI=20 and MOI=2. We chose NDV/HK84 as the candidate virus to test the oncolytic effect of NDV in HCC in the in vitro and in vivo experiments. NDV/HK84 killed human SK-HEP-1 HCC cells without affecting healthy cells.

CONCLUSIONS

Intratumor infection with NDV/HK84 strains compared with vehicle controls or positive controls indicated that NDV/HK84 strain specifically inhibited HCC without affecting healthy mice. High-throughput RNA sequencing showed that the oncolytic activity of NDV/HK84 was dependent on the activation of type I interferon signaling.

Dual stimuli-responsive dendronized prodrug derived from poly(oligo-(ethylene glycol) methacrylate)-based copolymers for enhanced anti-cancer therapeutic effect

In this study, we developed an enzyme- and pH-responsive dendronized poly(oligo-(ethylene glycol) methacrylate) (pOEGMA)-doxorubicin (DOX) polymeric prodrug, which combined the pOEGMA structure with a degradable peptide dendron. The introduction of the dendron in the prodrug hindered the entanglement of brush oligo-(ethylene glycol) (OEG) chains, allowed the prodrug to possess dual stimuli-responsiveness, and mediated self-assembly of the polymeric prodrug to form stable nanoparticles (NPs). Brush conformation of polyethylene glycol (PEG) side chains endowed the NPs with long-term circulation with a half-life of 16.0 h. The dual-responsive dendritic structure enhanced cellular uptake of NPs and facilitated drug release in response to overexpressed cathepsin B and an acidic pH in the tumor microenvironment, resulting in an enhanced therapeutic effect with a tumor inhibition rate of 72.9% for 4T1 tumor-bearing mice. The NPs were demonstrated to possess great hemocompatibility and biosafety. Therefore, this strategy could provide great insight for the design of poly(oligo-(ethylene glycol) methacrylate)-based copolymers as drug delivery carriers. STATEMENT OF SIGNIFICANCE: We propose a dual-stimuli-responsive dendronized strategy for improving the cancer therapeutic effect of the poly(oligo-(ethylene glycol) methacrylate) (pOEGMA)-based drug conjugates. The introduction of the functional dendron promotes self-assembly of the polymeric prodrug into nanoparticles, hindering the entanglement of brush oligo-(ethylene glycol) (OEG) chains in the conjugated drugs. The obtained poly OEGMA-GFLG-Dendron-NH-N=DOX nanoparticles maintains long circulation, while addresses the drug release issue due to the presence of high-density PEG. The drug delivery system exhibits a high therapeutic potentcy with negligible side effects.

Graphene-derived antibacterial nanocomposites for water disinfection: Current and future perspectives

Antimicrobial nanomaterials provide numerous opportunities for the synthesis of next-generation sustainable water disinfectants. Using the keywords graphene and water disinfection and graphene antibacterial activity, a detailed search of the Scopus database yielded 198 and 1433 studies on using graphene for water disinfection applications and graphene antibacterial activity in the last ten years, respectively. Graphene family nanomaterials (GFNs) have emerged as effective antibacterial agents. The current innovations in graphene-, graphene oxide (GO)-, reduced graphene oxide (rGO)-, and graphene quantum dot (GQD)-based nanocomposites for water disinfection, including their functionalization with semiconductor photocatalysts and metal and metal oxide nanoparticles, have been thoroughly discussed in this review. Furthermore, their novel application in the fabrication of 3D porous hydrogels, thin films, and membranes has been emphasized. The physicochemical and structural properties affecting their antibacterial efficiency, such as sheet size, layer number, shape, edges, smoothness/roughness, arrangement mode, aggregation, dispersibility, and surface functionalization have been highlighted. The various mechanisms involved in GFN antibacterial action have been reviewed, including the mechanisms of membrane stress, ROS-dependent and -independent oxidative stress, cell wrapping/trapping, charge transfer, and interaction with cellular components. For safe applications, the potential biosafety and biocompatibility of GFNs in aquatic environments are emphasized. Finally, the current limitations and future perspectives are discussed. This review may provide ideas for developing efficient and practical solutions using graphene-, GO-, rGO-, and GQD-based nanocomposites in water disinfection by rationally employing their unique properties.

Combination of chemistry and material science to overcome health problems

Since its outbreak, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has strongly influenced the life of the general public around the world. Based on its fast spread and high mortality, there is a need for novel therapeutic treatments to overcome this global health crisis. While medicinal chemistry is focused on the development of highly selective and affine inhibitors toward a specific target enzyme, material science is focused on the development of nanomaterials for selective drug delivery. Based on the individual strengths, these disciplines could synergistically act together and help overcome the limitations of the respective approach. Herein, the combination of medicinal chemistry with material science to overcome health problems with the example of SARS-CoV-2 is critically discussed.

Magnetic, biocompatible FeCO3 nanoparticles for T2-weighted magnetic resonance imaging of in vivo lung tumors

Background

Late diagnosis of lung cancer is one of the leading causes of higher mortality in lung cancer patients worldwide. Significant research attention has focused on the use of magnetic resonance imaging (MRI) based nano contrast agents to efficiently locate cancer tumors for surgical removal or disease diagnostics. Although contrast agents offer significant advantages, further clinical applications require improvements in biocompatibility, biosafety and efficacy.

Results

To address these challenges, we fabricated ultra-fine Iron Carbonate Nanoparticles (FeCO₃ NPs) for the first time via modified literature method. Synthesized NPs exhibit ultra-fine size (~ 17 nm), good dispersibility and excellent stability in both aqueous and biological media. We evaluated the MR contrast abilities of FeCO₃ NPs and observed remarkable T2 weighted MRI contrast in a concentration dependent manner, with a transverse relaxivity (r2) value of 730.9 ± 4.8 mM⁻¹ S⁻¹at 9.4 T. Moreover, the r2 values of present FeCO₃ NPs are respectively 1.95 and 2.3 times higher than the clinically approved contrast agents Resovist^® and Friedx at same 9.4 T MR scanner. FeCO₃ NPs demonstrate an enhanced T2 weighted contrast for in vivo lung tumors within 5 h of post intravenous administration with no apparent systemic toxicity or induction of inflammation observed in in vivo mice models.

Conclusion

The excellent biocompatibility and T2 weighted contrast abilities of FeCO₃ NPs suggest potential for future clinical use in early diagnosis of lung tumors.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01355-3.

Different characteristics of microbial diversity and special functional microbes in rainwater and topsoil before and after 2019 new coronavirus epidemic in Inner Mongolia Grassland

Grassland ecosystems are vital terrestrial ecosystems. As areas sensitive to climate change, they are critical for assessing the effects of global climate change. In China, grasslands account for over 40% of the land area. There is currently limited information on microbial diversity evolution in different grassland areas, particularly microorganisms with ice nucleation activity (INA) and their potential resources with potential influence to regulate regional precipitation and climate. We used Illumina MiSeq to sequence the 16S rRNA V3-V4 hypervariable region and performed a simple droplet freezing experiment to determine the variation in the grassland microbial community species composition and community structure. Rainwater and topsoil samples from the Hulunbuir Grassland in Inner Mongolia collected over three years were characterized. The dominant bacterial genus in the rainwater was Massilia, and the dominant fungus was Cladosporium. Additionally, the dominant bacteria in the soil were Sphingomonas, and the dominant fungus was Gibberella. There were differences in the microbial communities before and after the coronavirus disease epidemic. Pathogenic microorganisms exhibited inconsistent responses to environmental changes. The low relative abundance of known high-INA microorganisms and the higher freezing temperature indicated that unknown high-efficiency biological ice nucleating particles may be present. We found significant differences in species diversity and richness between the rainwater and soil populations in grassland areas by analyzing the sample community structures. Our research results revealed the species composition and structure of the microbiota in grassland ecosystems in China, indicating that environmental media and human activities may affect the microbiota in the grassland area and indicating underlying microorganisms with high INA.

High-efficient lignin-based polymerizable macromolecular photoinitiator with UV-blocking property for visible light polymerization

Developing high-efficient visible light macromolecular photoinitiator (macro PI) with excellent initiation performance, low migration, high biosafety and multi-function is beneficial to broaden the application of photopolymer. Lignin contains chromophores which could generate free radicals under light irradiation. In this study, a lignin-based polymerizable macro PI (DAL-11ene-amine) was designed and synthesized through covalent grafting 10-undecenoyl chloride (11ene) and hydrogen donor 4-(dimethylaminobenzoic acid) ethyl ester (EDAB) into dealkaline lignin (DAL) skeleton. The structure of DAL-11ene-amine was characterized by UV-vis, FTIR, ¹H NMR, GPC, and ³¹P NMR spectra. Under the irradiation of a 405 nm LED, DAL-11ene-amine can directly produce active species and initiate the polymerization of acrylate monomers or thiol-ene click reaction. The photoinitiation efficiency of DAL-11ene-amine is higher than that of DAL-11ene or the two-component combination of DAL-11ene and EDAB. Using DAL-11ene-amine as PI, the prepared polymer films exhibit excellent UV-blocking property. With only 0.5 wt% addition of DAL-11ene-amine, nearly 100% of UVB + UVC and the most of UVA can be blocked by the films. Moreover, DAL-11ene-amine exhibits higher migration stability and biosafety because it can be covalently linked into polymer cross-linking networks. The results indicate that DAL-11ene-amine has great application potentials in preparing environmentally friendly UV-blocking films and biosafety coatings.