Therapeutic and diagnostic potential of nanomaterials for enhanced biomedical applications

Nanomaterials in the treatment and diagnosis of rheumatoid arthritis: Advanced approaches

Rheumatoid arthritis (RA), a chronic inflammatory condition that affects persons between the ages of 20 and 40, causes synovium inflammation, cartilage loss, and joint discomfort as some of its symptoms. Diagnostic techniques for RA have traditionally been split into two main categories: imaging and serological tests. However, significant issues are associated with both of these methods. Imaging methods are costly and only helpful in people with obvious symptoms, while serological assays are time-consuming and require specialist knowledge. The drawbacks of these traditional techniques have led to the development of novel diagnostic approaches. The unique properties of nanomaterials make them well-suited as biosensors. Their compact dimensions are frequently cited for their outstanding performance, and their positive impact on the signal-to-noise ratio accounts for their capacity to detect biomarkers at low detection limits, with excellent repeatability and a robust dynamic range. In this review, we discuss the use of nanomaterials in RA theranostics. Scientists have recently synthesized, characterized, and modified nanomaterials and biomarkers commonly used to enhance RA diagnosis and therapy capabilities. We hope to provide scientists with the promising potential that nanomaterials hold for future theranostics and offer suggestions on further improving nanomaterials as biosensors, particularly for detecting autoimmune disorders.

Ferroptosis is involved in trophoblast cells cytotoxicity induced by black phosphorus nanoparticles

Black phosphorus (BP) is a new type of nanomaterial, which has been widely used in many biomedical fields due to its superior properties, but there are few studies on the toxicity of BP, especially in the reproductive system. To explore the effects of BP exposure on reproduction and reveal its molecular mechanism, we firstly investigated the potential toxicity of black phosphorus nanoparticles (BPNPs) in vivo. The results showed that BP exposure in pregnant mice can reduce the weight of fetal mice and placenta. H&E staining further indicated the changes of placental cross-section and vascular remodeling after BP treatment. Then, human exvillous trophoblast HTR8/SVneo was treated with different concentrations of BPNPs. We found that BPNPs induced significant cytotoxicity, including dose-dependent reduction of cell viability and proliferation. Trophoblast cell migration and invasion were also impaired by BPNPs exposure. Moreover, pretreatment with Cytochalasin D (Cyto-D), a classical phagocytic inhibitor, alleviated the decline of cell viability induced by BPNPs. Transcriptome sequencing showed that BPNPs exposure led to ferroptosis. Subsequently, the related indexes of ferroptosis were detected, including increase of iron ion concentration, decrease of the ferroptosis marker, GPX4 (Glutathione Peroxidase 4), increase of FTL (Ferritin Light Chain), and increase of lipid peroxidation indexes (MDA level and decrease of GSH level). In addition, ferroptosis inhibitors (Fer-1 and DFO) pretreatment can alleviate both the cytotoxic effects and functional impairment induced by BPNPs. In summary, our study confirmed the reproductive toxicity of BPNPs for the first time, and constructed BPNPs injury model in vitro using human villus trophoblast cells and revealed the role of ferroptosis in this process, which deepened our understanding of the biosafety of black phosphorus nanomaterials.

Interaction of zincite, alpha-terpineol, geranyl acetate, linalool, myrcenol, terpinolene, and thymol with virulence factors of Escherichia coli, Mycobacterium tuberculosis, Pseudomonas aeruginosa, and Staphylococcus aureus

BACKGROUND

Based on gas chromatography - mass spectrometry (GC-MS) results of a previous study, six metabolites including alpha-terpineol, geranyl acetate, linalool, myrcenol, terpinolene, and thymol showed significantly higher amounts relative to other metabolites.

METHODS

A continuation of the previous study, the interaction of these metabolites with the main virulence factors of P. aeruginosa (pseudomonas elastase and exotoxin A), Staphylococcus aureus (alpha-hemolysin and protein 2a), Mycobacterium tuberculosis (ESX-secreted protein B and the serine/threonine protein kinase), and Escherichia coli (heat-labile enterotoxin and Shiga toxin) were evaluated by molecular docking study and molecular simulation.

RESULTS

In the case of Shiga toxin, higher and lower binding affinities were related to alpha-terpinolene and zincite with values of -5.8 and -2.6 kcal/mol, respectively. For alpha-hemolysin, terpinolene and alpha-terpinolene demonstrated higher binding affinities with similar energies of -5.9 kcal/mol. Thymol and geranyl acetate showed lower binding energy of -5.7 kcal/mol toward protein 2a. Furthermore, thymol had a higher binding affinity toward heat-labile enterotoxin and ESX-secreted protein B with values of -5.9 and -6.1 kcal/mol, respectively.

CONCLUSIONS

It is concluded that the availability of secondary metabolites of A. haussknechtii surrounding zinc oxide (ZnO) NPs can hinder P. aeruginosa by inactivating Pseudomonas elastase and exotoxin.

Unveiling the molecular networks underlying cellular impairment in Saccharomyces cerevisiae: investigating the effects of magnesium oxide nanoparticles on cell wall integrity and endoplasmic reticulum stress response

Nanoparticles, particularly magnesium oxide nanoparticles (MgO-NPs), are increasingly utilized in various fields, yet their potential impact on cellular systems remains a topic of concern. This study aimed to comprehensively investigate the molecular mechanisms underlying MgO-NP-induced cellular impairment in Saccharomyces cerevisiae, with a focus on cell wall integrity, endoplasmic reticulum (ER) stress response, mitochondrial function, lipid metabolism, autophagy, and epigenetic alterations. MgO-NPs were synthesized through a chemical reduction method, characterized for morphology, size distribution, and elemental composition. Concentration-dependent toxicity assays were conducted to evaluate the inhibitory effect on yeast growth, accompanied by propidium iodide (PI) staining to assess membrane damage. Intracellular reactive oxygen species (ROS) accumulation was measured, and chitin synthesis, indicative of cell wall perturbation, was examined along with the expression of chitin synthesis genes. Mitochondrial function was assessed through Psd1 localization, and ER structure was analyzed using dsRed-HDEL marker. The unfolded protein response (UPR) pathway activation was monitored, and lipid droplet formation and autophagy induction were investigated. Results demonstrated a dose-dependent inhibition of yeast growth by MgO-NPs, with concomitant membrane damage and ROS accumulation. Cell wall perturbation was evidenced by increased chitin synthesis and upregulation of chitin synthesis genes. MgO-NPs impaired mitochondrial function, disrupted ER structure, and activated the UPR pathway. Lipid droplet formation and autophagy were induced, indicating cellular stress responses. Additionally, MgO-NPs exhibited differential cytotoxicity on histone mutant strains, implicating specific histone residues in cellular response to nanoparticle stress. Immunoblotting revealed alterations in histone posttranslational modifications, particularly enhanced methylation of H3K4me. This study provides comprehensive insights into the multifaceted effects of MgO-NPs on S. cerevisiae, elucidating key molecular pathways involved in nanoparticle-induced cellular impairment. Understanding these mechanisms is crucial for assessing nanoparticle toxicity and developing strategies for safer nanoparticle applications.

Nano-enhanced immunotherapy: Targeting the immunosuppressive tumor microenvironment

The tumor microenvironment (TME), which is mostly composed of tumor cells, immune cells, signaling molecules, stromal tissue, and the vascular system, is an integrated system that is conducive to the formation of tumors. TME heterogeneity makes the response to immunotherapy different in different tumors, such as "immune-cold" and "immune-hot" tumors. Tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells are the major suppressive immune cells and their different phenotypes interact and influence cancer cells by secreting different signaling factors, thus playing a key role in the formation of the TME as well as in the initiation, growth, and metastasis of cancer cells. Nanotechnology development has facilitated overcoming the obstacles that limit the further development of conventional immunotherapy, such as toxic side effects and lack of targeting. In this review, we focus on the role of three major suppressive immune cells in the TME as well as in tumor development, clinical trials of different drugs targeting immune cells, and different attempts to combine drugs with nanomaterials. The aim is to reveal the relationship between immunotherapy, immunosuppressive TME and nanomedicine, thus laying the foundation for further development of immunotherapy.

Gum Arabic assisted the biomass synthesis of bimetallic silver copper oxide nanoparticles using gamma-rays for improving bacterial and viral wound healing: Promising antimicrobial activity against foot and mouth disease

In this work, gamma irradiation was used to create bimetallic silver‑copper oxide nanoparticles (Ag-CuO NPs) in an ecologically acceptable way using gum Arabic (GA) polymer as a capping and reducing agent. Bimetallic Ag-CuO NPs were investigated through UV-Vis. spectroscopy, HR-TEM, SEM, DLS, and XRD examinations. The potency of antimicrobial and antibiofilm activities against a few bacterial isolates and Candida sp. had been investigated. Clinical investigations of 30 cows and 20 buffaloes from different sites in Egypt's Sharkia governorate found ulcerative lesions on the mouth and interdigital region. The cytotoxic assay of the generated NPs on BHK-21 was examined. The bimetallic Ag-CuO NPs had an average diameter of 25.58 nm, and the HR-TEM results showed that they were spherical. According to our results, Ag-CuO NPs exhibited the highest antibacterial efficacy against S. aureus (26.5 mm ZOI), K. pneumoniae (26.0 mm ZOI), and C. albicans (28.5 mm ZOI). The growth of biofilms was also successfully inhibited through the application of Ag-CuO NPs by 88.12 % against S. aureus, 87.08 % against C. albicans, and 74.0 % against B. subtilis. The ulcers on the mouth and foot of diseased animals healed in 4-5 days and 1 week, respectively, following topical application of bimetallic Ag-CuO NPs. The results examined the potential protective effects of a dosage of 3.57 μg/mL on cells before viral infection (cell control). According to our research, bimetallic Ag-CuO NPs limit the development of the virus that causes foot-and-mouth disease (FMD). The reduction of a specific FMD virus's cytopathic impact (CPE) on cell development represented the inhibitory effect when compared to identical circumstances without pretreatment with bimetallic Ag-CuO NPs. Their remarkable antibacterial properties at low concentration and continued-phase stability suggest that they may find widespread use in a variety of pharmacological and biological applications, especially in the wound-healing process.

Emerging Trends in Zinc Ferrite Nanoparticles for Biomedical and Environmental Applications

Over the last few decades, the application of nanoparticles (NPs) gained immense attention towards environmental and biomedical applications. NPs are ultra-small particles having size ranges from 1 to 100 nm. NPs loaded with therapeutic or imaging compounds have proved a versatile approach towards healthcare improvements. Among various inorganic NPs, zinc ferrite (ZnFe2O4) NPs are considered as non-toxic and having an improved drug delivery characteristics . Several studies have reported broader applications of ZnFe2O4 NPs for treating carcinoma and various infectious diseases. Additionally, these NPs are beneficial for reducing organic and inorganic environmental pollutants. This review discusses about various methods to fabricate ZnFe2O4 NPs and their physicochemical properties. Further, their biomedical and environmental applications have also been explored comprehensively.

Biosurfactant-capped CuO nanoparticles coated cotton/polypropylene fabrics toward antimicrobial textile applications

The global COVID-19 pandemic has led to an increase in the importance of implementing effective measures to prevent the spread of microorganisms. Consequently, there is a growing demand for antimicrobial materials, specifically antimicrobial textiles and face masks, because of the surge in diseases caused by bacteria and viruses like SARS-CoV-2. Face masks that possess built-in antibacterial properties can rapidly deactivate microorganisms, enabling reuse and reducing the incidence of illnesses. Among the numerous types of inorganic nanomaterials, copper oxide nanoparticles (CuO NPs) have been identified as cost-effective and highly efficient antimicrobial agents for inactivating microbes. Furthermore, biosurfactants have recently been recognized for their potential antimicrobial effects, in addition to inorganic nanoparticles. Therefore, this research's primary focus is synthesizing biosurfactant-mediated CuO NPs, integrating them into natural and synthetic fabrics such as cotton and polypropylene and evaluating the resulting fabrics' antimicrobial activity. Using rhamnolipid (RL) as a biosurfactant and employing a hydrothermal method with a pH range of 9-11, RL-capped CuO NPs are synthesized (RL-CuO NPs). To assess their effectiveness against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) microorganisms, the RL-CuO NPs are subjected to antibacterial testing. The RL-capped CuO NPs exhibited antimicrobial activity at much lower concentrations than the individual RL, CuO. RL-CuO NPs have shown a minimum inhibitory concentration (MIC) of 1.2 mg ml-1and minimum bactericidal concentration (MBC) of 1.6 mg ml-1forE. coliand a MIC of 0.8 mg ml-1and a MBC of 1.2 mg ml-1forS. aureus, respectively. Furthermore, the developed RL-CuO NPs are incorporated into cotton and polypropylene fabrics using a screen-printing technique. Subsequently, the antimicrobial activity of the coated fabrics is evaluated, revealing that RL-CuO NPs coated fabrics exhibited remarkable antibacterial properties against both gram-positive and gram-negative bacteria.

Influence of the Type of Biocompatible Polymer in the Shell of Magnetite Nanoparticles on Their Interaction with DPPC in Two-Component Langmuir Monolayers

Magnetite nanoparticles (MNPs) are attractive nanomaterials for applications in magnetic resonance imaging, targeted drug delivery, and anticancer therapy due to their unique properties such as nontoxicity, wide chemical affinity, and intrinsic superparamagnetism. Their functionalization with polymers such as chitosan or poly(vinyl alcohol) (PVA) can not only improve their biocompatibility and biodegradability but it also plays an important role in their interactions with biological cells. In this work, the effect of the functionalization of MNPs with chitosan, PVA, and their blend on model cell membranes formed from 1,2-dipalmitoyl-sn-glycerol-3-phosphocholine (DPPC) using a Langmuir technique was studied. The studies performed showed that the type of biocompatible polymer in the MNP shell plays a crucial role in the effectiveness of its adsorption process into the model cell membrane. Modification of MNPs with chitosan facilitates significantly more effective adsorption than coating them with PVA or with a chitosan and PVA blend. The presence of all the investigated MNPs in the DPPC monolayer at low concentrations does not affect its thermodynamic state, fluidity, or morphology, which is promising in terms of their biocompatibility. On the other hand, their high concentration (molar fraction above ≈0.05) exerts a disruptive effect on the model cell membrane and results in their aggregation, leading probably to the loss of their superparamagnetic properties essential for nanomedicine.

Nanocomposite based on Gd2O3 nanoparticles and drug 5-fluorouracil as potential theranostic nano-cargo system

We have prepared silica matrix with hexagonal symmetry of pores (SBA-15) and loaded it with anticancer drug 5-Fluorouracil (5-FU) to promote it as a drug delivery system. Gd2O3 nanoparticles were incorporated into the matrix to enhance nanosystems applicability as contrast agent for MRI, thus enabled this nanocomposite to be used as multifunctional nano-based therapeutic agent. Drug release profile was obtained by UV-VIS spectroscopy, and it indicates the prolongated release of 5-FU during the first hours and the total release after 5 h. The cytotoxicity tests using MTT-assay, fluorescent microscopy, bright-field microscopy, and flow cytometry were carried out using human glioma U87 MG cells and SK BR 3 cells. The nanocomposite with anticancer drug (Gd2O3/SBA-15/5FU) showed toxic behaviour towards studied cells, unlike nanocomposite without drug (Gd2O3/SBA-15) that was non-toxic. Our drug delivery system was designed to minimalize negative effect of Gd3+ ions at magnetic resonance imaging and drug 5-FU on healthy cells due to their encapsulation into biocompatible silica matrix, so the Gd3+ ions are more stable (in comparison to chelates), lower therapeutic dose of 5-FU is needed and its prolongated release from silica pores was confirmed. Very good T1 contrast in MR images was observed even at low concentrations, thus this nanosystem can be potentially used as contrast imaging agent.

Artificially induced in situ macrophage polarization: An emerging cellular therapy for immuno-inflammatory diseases

Macrophages are the mature form of monocytes that have high plasticity and can shift from one phenotype to another by the process of macrophage polarization. Macrophage has several vital pharmacological tasks like eliminating microorganism invasion, clearing dead cells, causing inflammation, repairing damaged tissues, etc. The function of macrophages is based on their phenotype. M1 macrophages are mostly responsible for the body's immune responses and M2 macrophages have healing properties. Inappropriate activation of any one of the phenotypes often leads to ROS-induced tissue damage and affects wound healing and angiogenesis. Therefore, maintaining tissue macrophage homeostasis is necessary. Studies are being done to find techniques for macrophage polarization. But, the process of macrophage polarization is very complex as it involves multiple signalling pathways involving innate immunity. Thus, identifying the right pathways for macrophage polarization is essential to apply the polarizing technique for the treatment of various inflammatory diseases where macrophage physiology influences the disease pathology. In this review, we highlighted the various techniques so far used to change macrophage plasticity. We believe that soon macrophage targeting therapeutics will hit the market for the management of inflammatory disease. Hence this review will help macrophage researchers choose suitable methods and materials/agents to polarize macrophages artificially in various disease models.

Pomegranate Peel Extract Stabilized Selenium Nanoparticles Synthesis: Promising Antimicrobial Potential, Antioxidant Activity, Biocompatibility, and Hemocompatibility

The green synthesis of selenium nanoparticles (Se NPs) had been synthesized by pomegranate peel extract (PPE). The antimicrobial, antioxidant, and anticancer activities of the synthesized Se NPs, as well as their hemocompatibility, were investigated. Se NPs were characterized by UV-Vis., SEM, XRD, HR-TEM, DLS, EDX, FTIR, and mapping techniques. HR-TEM image represented the spheroidal forms with moderately monodispersed NPs with a mean diameter 14.5 nm. The SEM image of Se NPs, incorporated with PPE, exhibits uniform NP surfaces, and the appearance was clear. The antimicrobial results confirmed the potential of Se NPs to hinder the growth of some tested pathogenic microbes. Results revealed that Se NPs exhibited promising antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, and Streptococcus mutans where inhibition zones were 29, 16, 41, 22, and 54 mm, respectively. Likewise, it exhibited antifungal activity where the values of inhibition zones were 41, 40, 38, and 36 mm against Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, and A. niger, respectively. The antioxidant activities of Se NPs at concentrations 250-4000 µg/mL were greater than 90% in all cases. Se NP concentrations of 500 µg/mL or less are safe in usage according to hemocompatibility study. Se NPs had an IC50 of 113.73 µg/mL in a cytotoxicity experiment. Results revealed that Se NPs have promising anticancer activities against MCF7 and Mg63 cancerous cell line, where IC50 was 69.8 and 47.9 μg/mL, respectively. In conclusion, Se NPs were successfully biosynthesized using PPE for the first time; these Se NPs had promising antimicrobial, antioxidant, and anticancer activities.

Potential antibacterial, antibiofilm, and photocatalytic performance of gamma-irradiated novel nanocomposite for enhanced disinfection applications with an investigated reaction mechanism

BACKGROUND

Water scarcity is now a global challenge due to the population growth and the limited amount of available potable water. In addition, modern industrialization, and microbial pathogenesis is resulting in water pollution on a large scale.

METHODS

In the present study, reusable Co0.5Ni0.5Fe2O4/SiO2/TiO2 composite matrix was incorporated with CdS NPs to develop an efficient photocatalyst, and antimicrobial agents for wastewater treatment, and disinfection purpose. The antibacterial performance of the gamma-irradiated samples was evaluated against various types of Gram-positive bacteria using ZOI, MIC, antibiofilm, and effect of UV-exposure. Antibacterial reaction mechanism was assessed by bacterial membrane leakage assay, and SEM imaging. In addition, their photocatalytic efficiency was tested against MB cationic dye as a typical water organic pollutant.

RESULTS

Our results showed that, the formed CdS NPs were uniformly distributed onto the surface of the nanocomposite matrix. While, the resulted CdS-based nanocomposite possessed an average particle size of nearly 90.6 nm. The antibacterial performance of the prepared nanocomposite was significantly increased after activation with gamma and UV irradiations. The improved antibacterial performance was mainly due to the synergistic effect of both TiO2 and CdS NPs; whereas, the highest photocatalytic efficiency of MB removal was exhibited in alkaline media due to the electrostatic attraction between the cationic MB and the negatively-charged samples. In addition, the constructed heterojunction enabled better charge separation and increased the lifetime of the photogenerated charge carriers.

CONCLUSION

Our results can pave the way towards the development of efficient photocatalysts for wastewater treatment and promising antibacterial agents for disinfection applications.

Gamma rays-assisted bacterial synthesis of bimetallic silver-selenium nanoparticles: powerful antimicrobial, antibiofilm, antioxidant, and photocatalytic activities

BACKGROUND

Bimetallic nanoparticles (BNPs) has drawn a lot of attention especially during the last couple of decades. A bimetallic nanoparticle stands for a combination of two different metals that exhibit several new and improved physicochemical properties. Therefore, the green synthesis and design of bimetallic nanoparticles is a field worth exploring.

METHODS

In this study, we present a green synthesis of silver nanoparticles (Ag NPs), selenium (Se) NPs, and bimetallic Ag-Se NPs using Gamma irradiation and utilizing a bacterial filtrate of Bacillus paramycoides. Different Techniques such as UV-Vis., XRD, DLS, SEM, EDX, and HR-TEM, were employed for identifying the synthesized NPs. The antimicrobial and antibiofilm activities of both the Ag/Se monometallic and bimetallic Ag-Se NPs were evaluated against some standard microbial strains including, Aspergillus brasiliensis ATCC16404, Candida albicans ATCC10231, Alternaria alternate EUM108, Fusarium oxysporum EUM37, Escherichia coli ATCC11229, Bacillus cereus ATCC15442, Klebsiella pneumoniae ATCC13883, Bacillus subtilis ATCC15442, and Pseudomonas aeruginosa ATCC6538 as a model tested pathogenic microbes. The individual free radical scavenging potentials of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs were determined using the DPPH radical scavenging assay. The degradation of methylene blue (MB) dye in the presence of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs was used to assess their photocatalytic behavior.

RESULTS

According to the UV-Vis. spectrophotometer, the dose of 20.0 kGy that results in Ag NPs with the highest O.D. = 3.19 at 390 nm is the most effective dose. In a similar vein, the optimal dose for the synthesis of Se NPs was 15.0 kGy dose with O.D. = 1.74 at 460 nm. With a high O.D. of 2.79 at 395 nm, the most potent dose for the formation of bimetallic Ag-Se NPs is 15.0 kGy. The recorded MIC-values for Ag-Se NPs were 62.5 µg mL- 1, and the data clearly demonstrated that C. albicans was the organism that was most susceptible to the three types of NPs. The MIC value was 125 µg mL- 1 for both Ag NPs and Se NPs. In antibiofilm assay, 5 µg mL- 1 Ag-Se NPs inhibited C. albicans with a percentage of 90.88%, E. coli with a percentage of 90.70%, and S. aureus with a percentage of 90.62%. The synthesized NPs can be arranged as follows in decreasing order of antioxidant capacity as an antioxidant result: Ag-Se NPs > Se NPs > Ag NPs. The MB dye degradation in the presence of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs was confirmed by the decrease in the measured absorbance (at 664 nm) after 20 min of exposure to sunlight.

CONCLUSION

Our study provides insight towards the synthesis of bimetallic NPs through green methodologies, to develop synergistic combinatorial antimicrobials with possible applications in the treatment of infectious diseases caused by clinically and industrial relevant drug-resistant strains.

Recent progress in the effect of magnetic iron oxide nanoparticles on cells and extracellular vesicles

At present, iron oxide nanoparticles (IONPs) are widely used in the biomedical field. They have unique advantages in targeted drug delivery, imaging and disease treatment. However, there are many things to pay attention to. In this paper, we reviewed the fate of IONPs in different cells and the influence on the production, separation, delivery and treatment of extracellular vesicles. It aims to provide cutting-edge knowledge related to iron oxide nanoparticles. Only by ensuring the safety and effectiveness of IONPs can their application in biomedical research and clinic be further improved.

Statistical optimization and characterization of monodisperse and stable biogenic gold nanoparticle synthesis using Streptomyces sp. M137-2

Microbial synthesis of gold nanoparticles (AuNPs), which are used in various forms with different properties in medicine, as a renewable bioresource has become increasingly important in recent years. In this study, statistical optimization of stable and monodispersed AuNPs synthesis was performed using a cell-free fermentation broth of Streptomyces sp. M137-2 and AuNPs were characterized, and their cytotoxicity was determined. The three factors determined as pH, gold salt (HAuCl₄) concentration, and incubation time, which are effective in the extracellular synthesis of biogenic AuNPs, were optimized by Central Composite Design (CCD) and then UV-Vis Spectroscopy, Dynamic Light Scattering (DLS), X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Scanning Transmission Electron Microscope (STEM), size distribution, Fourier-Transform Infrared (FT-IR) Spectroscopy, X-Ray Photoelectron Spectrophotometer (XPS) and stability analyzes of AuNPs were carried out. Optimum values of the factors were determined as pH 8, 10^- 3 M HAuCl₄, and 72 h incubation using Response Surface Methodology (RSM). Almost spherical AuNPs with 20-25 nm protein corona on the surface, 40-50 nm in size, monodisperse, and highly stable form were synthesized. Biogenic AuNPs were confirmed from characteristic diffraction peaks in the XRD pattern, UV-vis peak centred at 541 nm. The FT-IR results confirmed the role of Streptomyces sp. M137-2 metabolites in the reduction and stabilization of AuNPs. The cytotoxicity results also showed that AuNPs obtained using Streptomyces sp. can be used safely in medicine. This is the first report to perform statistical optimization of size-dependent biogenic AuNPs synthesis using a microorganism.

Zinc oxide loaded chitosan-elastin-sodium alginate nanocomposite gel using freeze gelation for enhanced adipose stem cell proliferation and antibacterial properties

Hydrogels have been the material of choice for regenerative medicine applications due to their biocompatibility that can facilitate cellular attachment and proliferation. The present study aimed at constructing a porous hydrogel composite scaffold (chitosan, sodium alginate and elastin) for the repair of chronic skin wounds. Chitosan-based hydrogel incorporating varying concentrations of zinc oxide nanoparticles i.e. ZnO-NPs (0, 0.001, 0.01, 0.1 and 1 % w/w) as the antimicrobial agent tested against Escherichia coli (E.coli) and Staphylococcus aureus (S. aureus) exhibited good antibacterial activities. ZnO-NPs were characterized by UV visible spectroscopy, Scanning electron microscopy (SEM) analysis, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. Fabricated gels were characterized by SEM analysis, FTIR, XRD, swelling ratio, degradation behavior and controlled release kinetics of ZnO-NPs. In vitro cytocompatibility of the composite was investigated using human adipose stem cells (ADSCs) by MTT and lactate dehydrogenase (LDH) assay, further assessed by SEM analysis and PKH26 staining. The SEM and XRD analysis confirmed the successful loading of ZnO-NPs into these scaffolds. Fluorescence PKH26 stained images and SEM analysis of ADSCs seeded scaffolds revealed biocompatible nature. The findings suggested that the developed composite gels have potential clinically for tissue engineering and chronic wound treatment.

Manganese Dioxide Nanoparticles Prepared by Laser Ablation as Materials with Interesting Electronic, Electrochemical, and Disinfecting Properties in Both Colloidal Suspensions and Deposited on Fluorine-Doped Tin Oxide

Nanoparticles (NPs) of α-MnO₂ have high applicability in photoelectrochemical, heterogeneous photocatalysis, optical switching, and disinfection processes. To widen this panorama about MnO₂ NPs, the formation of this material by laser ablation and deposition by dip-coating on fluorine-doped tin oxide (FTO), were considered in this study. The optical, spectroscopic, electrochemical characterization, and the evaluation of the antimicrobial activity, plus the photocatalytic response, were measured herein in colloidal media and deposited. For the deposition of NPs on FTO sheet, an anode is produced with a pseudocapacitive behavior, and 2.82 eV of band gap (GAP) in comparison with colloidal NPs for a value of 3.84 eV. Both colloidal suspension and deposited NPs have intrinsic antibacterial activity against two representative microorganisms (E. coli and S. aureus), and this biological activity was significantly enhanced in the presence of UVA light, indicating photocatalytic activity of the material. Thus, both the colloidal suspension and deposited NPs can act as disinfecting agents themselves or via light activation. However, an antibacterial behavior different for E. coli and S. aureus was observed, in function of the aggregation state, obtaining total E. coli disinfection at 30 min for deposited samples on FTO.

Gamma Radiation Induced Synthesis of Novel Chitosan/Gold/Bioactive Glass Nanocomposite for Promising Antimicrobial, and Antibiofilm Activities

In the present study we reported, for the first time, the gamma irradiation induced synthesis of chitosan/Au/bioactive glass (CS/Au/BG) nanocomposite. The bioactive glass (BG), with the composition 45% SiO2, 32.5% CaO, 15% Na2O, and 7.5% P2O5 wt% was synthesized through the sol–gel technique. XRD, SEM, EDX, and elemental mapping images were utilized to evaluate the structure of pure BG and CS/Au/BG nanocomposite. The antimicrobial efficacy was evaluated by zone of inhibition (ZOI), minimum inhibitory concentration (MIC), growth curve assay, and Ultraviolet irradiation effect. Investigation was carried on the antibiofilm effectiveness. Membrane leakage as well as SEM imaging were used to evaluate the antibacterial reaction mechanism. The crystallite size of CS/Au/BG nanocomposite was determined via Scherer equation as 22.83 nm. CS/Au/BG possessed the most ZOI activity against the tested microbes. The highest inhibition % of BG, and CS/Au/BG nanocomposite was investigated for S. aureus (15.65%, and 77.24%), followed by C. albicans (13.32%, and 64.75%). The quantity of protein leakage was directly-proportional after increasing the concentration of BG, and CS/Au/BG and counted to be 70.58, and 198.25 µg/mL, respectively (after applied 10 mg/mL). The promising results suggested the use of novel CS/Au/BG nanocomposite as an encourage candidate for wastewater treatment application against pathogenic microbes.

The emergence of metal oxide nanoparticles (NPs) as a phytomedicine: A two-facet role in plant growth, nano-toxicity and anti-phyto-microbial activity

Anti-microbial resistance (AMR) has recently emerged as an area of high interest owing to the rapid surge of AMR phenotypes. Metal oxide NPs (MeONPs) have been identified as novel phytomedicine and have recently peaked a lot of interest due to their potential applications in combating phytopathogens, besides enhancing plant growth and yields. Numerous MeONPs (Ti₂O, MgO, CuO, Ag₂O, SiO₂, ZnO, and CaO) have been synthesized and tested to validate their antimicrobial roles without causing toxicity to the cells. This review discusses the application of the MeONPs with special emphasis on anti-microbial activities in agriculture and enlists how cellular toxicity caused through reactive oxygen species (ROS) production affects plant growth, morphology, and viability. This review further highlights the two-facet role of silver and copper oxide NPs including their anti-microbial applications and toxicities. Furthermore, the factor modulating nanotoxicity and immunomodulation for cytokine production has also been discussed. Thus, this article will not only provide the researchers with the potential bottlenecks but also emphasizes a comprehensive outline of breakthroughs in the applicability of MeONPs in agriculture.

Radiation synthesis and in vitro evaluation of the antimicrobial property of functionalized nanopolymer-based poly (propargyl alcohol) against multidrug-resistance microbes

Pathogenic microorganisms are responsible for many diseases in biological organisms, including humans. Many of these infections thrive in hospitals, where people are treated with medicines and certain bacteria resist those treatments. Consequently, this research article aims to develop efficient antimicrobial material-based conjugated and functionalized polypropargyl alcohol nanoparticles (nano-PGA) synthesized by gamma irradiation. The monomer of PGA was polymerized in various mediums (water (W), chloroform (Ch), and dimethylformamide (DMF)) without catalysts under the action of γ-rays, producing π-conjugated and colored functional nano-PGA polymers. Nano-PGA is a versatile polymer demonstrated here as suitable for creating next-generation of antimicrobial systems capable of effectively preventing and killing various pathogenic microorganisms. The novelty here is the development of polymeric nanostructures by changing the solvent and irradiation doses. The antimicrobial property of nano-PGA (nanostare-like antibody structure) was examined against different pathogenic bacteria and unicellular fungi. Nano-PGA-DMF exhibits significant antimicrobial potential against Staphylococcus aureus (S. aureus) (20.20 mm; zone of inhibition (ZOI), and 0.47 μg/mL; minimum inhibitory concentration (MIC), followed by Escherichia coli (E. coli) (14.50 mm; ZOI, and 1.87 μg/mL; MIC, and Candida albicans (C.albicans) (12.50 mm; ZOI, and 1.87 μg/mL; MIC). In antibiofilm results, the highest inhibition percentage of the synthesized nano-PGA-W, nano-PGA-Ch, and nano-PGA-DMF was documented for S. aureus (17.01%, 37.57%, and 80.27%), followed by E. coli (25.68%, 55.16% and 78.11%), and C.albicans (40.10%, 62.65%, and 76.19%), respectively. The amount of bacterial protein removed is directly proportional after increasing the concentration of nano-PGA-W, nano-PGA-Ch, and nano-PGA-DMF samples (at different concentrations) and counted to be 70.58, 102.89, and 200.87 μg/mL, respectively following the treatment with 1.0 mg/mL of each sample. It was found that the nano-PGA polymer prepared in DMF has better antimicrobial activity than one prepared in chloroform than in water.

Cefotaxime incorporated bimetallic silver-selenium nanoparticles: promising antimicrobial synergism, antibiofilm activity, and bacterial membrane leakage reaction mechanism

In this research, we reported for the first time the simple incorporation of antibiotic cefotaxime (CFM) with the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs by gamma rays, as a promising cost-effective, and eco-friendly method. The synthesized nanocomposites were characterized by UV-Vis. spectroscopy, XRD, EDX, HR-TEM, SEM/mapping, and EDX studies. The antimicrobial synergistic potential was investigated after CFM drug incorporation. Antibiofilm activity, growth curve assay, and effect of UV illumination were examined against some pathogenic microbes. The antibacterial reaction mechanism was evaluated by protein leakage assay and SEM imaging. HRTEM imaging confirmed the spherical shape and an average diameter of 10.95, 20.54, and 12.69 nm for Ag NPs, Se NPs, and Ag-Se NPs, respectively. Ag NPs-CFM, Se NPs-CFM, and Ag-Se NPs-CFM possessed antimicrobial activity against Staphylococcus aureus (40, 42, and 43 mm ZOI, respectively), Escherichia coli (33, 35, and 34 mm ZOI, respectively) and Candida albicans (25, 22, and 23 mm ZOI, respectively). CFM-incorporated Ag-Se NPs were able to inhibit biofilm formation of S. aureus (96.09%), E. coli (98.32%), and C. albicans (95.93%). Based on the promising results, the synthesized nanocomposites showed superior antimicrobial potential at low concentrations and continued-phase durability; they may find use in pharmaceutical, and biomedical applications.

Use of quasi-SMILES to build models based on quantitative results from experiments with nanomaterials

Quasi-SMILES deviate from traditional SMILES (simplified molecular input-line entry system) by the extension of additional symbols that encode for conditions of an experiment. Descriptors calculated with SMILES are useful for the development of quantitative structure-property/activity relationships (QSPRs/QSARs), while descriptors calculated with quasi-SMILES can be useful for the development of quantitative models of experimental results obtained under different conditions. Here, this approach has been applied for the development of generalized models using aquatic nanotoxicity data (i.e., related to fish and daphnia). The statistical quality of the above models (pLC50) is quite good with a determination coefficient for the external validation set ranging from 0.62 to 0.71 and RMSE ranging from 0.58 to 0.60. The principle of the approach includes splitting the experimental data into three random distributions defining training, calibration, and validation sets.

Antimicrobial, and Antibiofilm Activities of Silver Doped Hydroxyapatite: A Novel Bioceramic Material for Dental Filling

Even though hydroxyapatite (HA) is the most common biocompatible material; it has limited antibacterial resistance. HA experiences a tailor-made structure depending on the desired applications. In this regard, silver (Ag) is of particular interest to inhibit wide spectrum of pathogenic bacteria and other microorganisms. Silver doped hydroxyapatite (Ag-HA) was developed via wet co-precipitation with subsequent hydrothermal processing to hinder the growth and multiplication of pathogenic microbes. Ag-HA demonstrated mono-dispersed nano-rods of 70 nm length and 7 nm diameters. Even though silver dopant induced stresses within the crystal lattice; Ag-HA maintained the crystallographic structure of HA with no change. Ag-HA nanocomposite demonstrated Ca/P value of 1.238 compared with 1.402 for virgin HA via XPS spectroscopy. The reduction of Ca/P value was correlated to the partial replacement of Ca+2 with Ag+1; Silver content was reported to be of 1 atomic %. Elemental mapping using EDAX confirmed uniform dispersion of silver ion within HA lattice. Antimicrobial results indicated that, Ag-HA nanocomposite demonstrated the most potent zone of inhibition (ZOI) against Staphylococcus aureus, and Candida albicans. Antibiofilm results indicated that Ag-HA nanocomposite at 10.0 µg/mL, experienced the highest percentage for S. aureus and C. albicans of 96.09%, and 77.77%, respectively. Ag-HA nanocomposite demonstrated an excellent disinfectant agent once it had excited by UV light. In growth curve assay, the OD600 value of Ag- HA were lower, showing the repression impact on the growth of S. aureus. It was observed that the quantity of cellular protein discharged from S. aureus is directly proportional to the concentration of Ag-HA, which proves the antibacterial characteristics of the Ag-HA nanocomposite, and explains the creation of holes in the bacterial membrane producing the oozing out of the proteins from the S. aureus cytoplasm. Ag-HA nanocomposite achieved the complete lysis of the bacterial cell and cell malformation, decreasing the total viable number, so the outstanding antimicrobial results encouraged the tooth filling biomedical applications.

Graphical Abstract

Sulfur-doped graphitic carbon nitride nanosheets as a sensitive fluorescent probe for detecting environmental and intracellular Ag

Silver is widely used in medical materials, photography, electronics and other industries as a precious metal. The large-scale industrial production of silver-containing products and liquid waste emissions aggravate the environmental pollution. Silver ion is one of the most toxic metal ions, causing pollution to the environment and damage to public health. Therefore, the efficient and sensitive detection of Ag+ in the water environment is extremely important. Sulfur-doped carbon nitride nanosheets (SCN Ns) were prepared by melamine and thiourea via high-temperature calcination. The morphology, chemical composition and surface functional groups of the SCN Ns were characterized by SEM, TEM, XRD, XPS, and FT-IR. The fluorescence of SCN Ns was gradually quenched as the Ag+ concentration increased. The detection limit for Ag+ was as low as 0.28 nM. The quenching mechanism mainly is attributed to static quenching. In this paper, SCN Ns were used as the fluorescent probe for detecting Ag+. SCN Ns have successfully detected Ag+ in different environmental aqueous samples and cells. Finally, SCN Ns were further applied to the visual quantitative detection of intracellular Ag+.

Silver nanoparticles coated medical fiber synthesized by surface engineering with bio-inspired mussel powered polydopamine: An investigated antimicrobial potential with bacterial membrane leakage reaction mechanism

Nature frequently provides narrative biological motivation. This study reports on oxygen-induced auto-polymerization of dopamine on the surface of medical cotton fibers to develop super-hydrophobic surfaces. The versatile reactivity of polydopamine (PDA) surfactant was adopted to deposit silver nanoparticles (Ag NPs) on the surface of medical cotton. SEM micrographs demonstrated the uniform deposition of Ag NPs. The antimicrobial reactivity confirmed the potential of Ag-loaded PDA-cotton fiber to hinder the growth of some tested pathogenic microbes. Silver-loaded PDA-cotton fibers showed the most promising zone of inhibition (ZOI) against (33.5 mm), Candida tropicalis (30.2 mm), and Aspergillus niger (30.2 mm). In growth curve assay, after addition of silver-loaded PDA-cotton fibers, the O.D. were lower (0.365 nm), showing the repression impact on S. aureus. It was observed that the quantity of cellular protein discharged from S. aureus is directly proportional to the concentration of silver-loaded PDA-cotton fibers and found to be 159.68 μg/ml after the treatment with silver-loaded PDA-cotton fibers (2 cm × 2 cm), which proves the antibacterial characteristics of the synthesied silver-loaded PDA-cotton fibers. The obtained antimicrobial results gives solution in treating pathogenic microbes and the application of silver-loaded PDA-cotton fibers as wound dressing in biomedical and pharmaceutical fields.

Enhanced photocatalytic and antimicrobial performance of a multifunctional Cu-loaded nanocomposite under UV light: theoretical and experimental study

Due to modern industrialization and population growth, access to clean water has become a global challenge. In this study, a metal-semiconductor heterojunction was constructed between Cu NPs and the Co_0.5Ni_0.5Fe₂O₄/SiO₂/TiO₂ composite matrix for the photodegradation of potassium permanganate, hexavalent chromium Cr(VI) and p-nitroaniline (pNA) under UV light. In addition, the electronic and adsorption properties after Cu loading were evaluated using density functional theory (DFT) calculations. Moreover, the antimicrobial properties of the prepared samples toward pathogenic bacteria and unicellular fungi were investigated. Photocatalytic measurements show the outstanding efficiency of the Cu-loaded nanocomposite compared to that of bare Cu NPs and the composite matrix. Degradation efficiencies of 44% after 80 min, 100% after 60 min, and 65% after 90 min were obtained against potassium permanganate, Cr(VI), and pNA, respectively. Similarly, the antimicrobial evaluation showed high ZOI, lower MIC, higher protein leakage amount, and cell lysis of nearly all microbes treated with the Cu-loaded nanocomposite.

Effects of oppositely charged moieties on the self-assembly and biophysicochemical properties of polyurethane micelles

Gemini quaternary ammonium (GQA), a type of cationic surfactant, exhibits excellent micellization ability and acts as a cell internalization promoter to increase the permeability of the cell membrane. GQA is sensitive to ionic solutions, which disturb its stabilization and leads to the rapid degradation of its polymer micelles due to its unique hydrophilic N⁺ structure. However, the effect of negatively charged moieties in the polymer chains of GQA on its action in polymer micelles, typically with regard to its micellization and biological performance, remains unclear. In this work, a series of polyurethane micelles containing various ratios of oppositely charged moieties was prepared. We found that the interchain electrostatic interaction severely undermines the function of the GQA surfactant and hinders the self-assembly and stabilization of polyurethane micelles. Specifically, a hydrophilic corona with a longer length cannot completely overcome this effect. By regulating the ratio of oppositely charged moieties, micelles exhibited tunable biological properties, such as biocompatibility, cytotoxicity, cell internalization, and phagocytosis by macrophages. Based on our results, a moderate molecular weight of mPEG (Mn = 1900) and a slight positive surface potential (∼10 mV) are the best surface parameters for the comprehensive performance of the studied nanoplatforms. This study provides a further understanding of the electrostatic interaction effect on the properties of the cationic GQA, offering rational guidance for the design and fabrication of GQA polymer micelles.

The Effect of Nano-chitosan and Nano-curcumin on Radiated Parotid Glands of Albino Rats: Comparative Study

Decreasing the salivary flow rate manifested by xerostomia occurs early during the irradiation treatment. The duration of depressed salivary function varies among patients. Various histopathological changes occur in the salivary glands. The current study was performed to investigate and compare between the possible anti-radiotherapeutic effect of the gamma rays-synthesized curcumin nanoparticles (Cur NPs), and chitosan nanoparticles (Cs NPs). They were utilized to overcome the histopathological changes associated with radiation therapy in albino rats’ parotid glands. Sixty adult male Albino rats were utilized, fifteen as control group, fifteen as radiated group and thirty as Cur NPs and Cs NPs treatment groups. The parotid glands were dissected and examined histologically, immunohistochemically for vascular endothelial growth factor (VEGF) as well as histo-morphometrically. The histological results proved the antiradio-therapeutic effect of Cur NPs, and Cs NPs, with the least degenerative changes in the Cur NPs treated group. A high significant increase in VEGF was recorded in the radiated group as compared to the other treated groups. Cs NPs have proved to be an anti-radiotherapeutic and anti-oxidant substrate in treating the histopathological changes in radiated parotid glands of albino rats. However, it was lagging behind Cur NPs in all analyses but non-significant differences between them have been recorded.

Graphical Abstract

Porphyrin NanoMetal-Organic Frameworks as Cancer Theranostic Agents

Metal-Organic Frameworks (MOFs) are hybrid multifunctional platforms that have found remarkable applications in cancer treatment and diagnostics. Independently, these materials can be employed in cancer treatment as intelligent drug carriers in chemotherapy, photothermal therapy, and photodynamic therapy; conversely, MOFs can further be used as diagnostic tools in fluorescence imaging, magnetic resonance imaging, computed tomography imaging, and photoacoustic imaging. One essential property of these materials is their great ability to fine-tune their composition toward a specific application by way of a judicious choice of the starting building materials (metal nodes and organic ligands). Moreover, many advancements were made concerning the preparation of these materials, including the ability to downsize the crystallites yielding nanoporous porphyrin MOFs (NMOFs) which are of great interest for clinical treatment and diagnostic theranostic tools. The usage of porphyrins as ligands allows a high degree of multifunctionality. Historically these molecules are well known for their reactive oxygen species formation and strong fluorescence characteristics, and both have proved helpful in cancer treatment and diagnostic tools. The anticipation that porphyrins in MOFs could prompt the resulting materials to multifunctional theranostic platforms is a reality nowadays with a series of remarkable and ground-breaking reports available in the literature. This is particularly remarkable in the last five years, when the scientific community witnessed rapid development in porphyrin MOFs theranostic agents through the development of imaging technologies and treatment strategies for cancer. This manuscript reviews the most relevant recent results and achievements in this particular area of interest in MOF chemistry and application.

Construction of targeted delivery system for curcumin loaded on magnetic α-Fe2O3/Fe3O4 heterogeneous nanotubes and its apoptosis mechanism on MCF-7 cell

In this work, the magnetic α-Fe₂O₃/Fe₃O₄ heterogeneous nanotubes were successfully prepared by solvent hydrothermal-controlled calcination method. The effects of additive concentration, hydrothermal temperature and time on morphology of products were investigated. The α-Fe₂O₃/Fe₃O₄ nanotubes with a saturation magnetization of 50 emu/g were prepared calcinated at 600 °C for 4 h using 0.8 g of glucose. Their average length, the outer and inner diameters were around 240 nm, 178 nm and 145 nm, respectively. The α-Fe₂O₃/Fe₃O₄ heterogeneous nanotubes coated with water-soluble liposome were applied for targeted delivery of curcumin. The release of curcumin inside the hollow structure of the nanocomposites could be triggered and effectively sustained represented a process of slow release. The encapsulation efficiency of curcumin in the α-Fe₂O₃/Fe₃O₄-CUR@LIP nanocomposites reached 82.1 ± 0.9%. MTT assays demonstrated that blank carriers had excellent biocompatibility and application of magnetic field significantly elevated the cytotoxicity of α-Fe₂O₃/Fe₃O₄-CUR@LIP nanocomposites on MCF-7 cell. Electrochemical experiment and Prussian blue staining indicated that the α-Fe₂O₃/Fe₃O₄@LIP nanocomposites could aggregate in cells to promote the internalization of curcumin. Magnetic α-Fe₂O₃/Fe₃O₄-CUR@LIP nanocomposites and curcumin enhanced the expression of reactive oxygen species in MCF-7 cells and induced apoptosis by fluorescence detection. Flow cytometry and western blot verified that the α-Fe₂O₃/Fe₃O₄@LIP nanocomposites under magnetic field enhanced cells late-apoptosis by adjusting the expression of apoptosis-related proteins.

Surface Engineering of Nanomaterials with Polymers, Biomolecules, and Small Ligands for Nanomedicine

Nanomedicine is a speedily growing area of medical research that is focused on developing nanomaterials for the prevention, diagnosis, and treatment of diseases. Nanomaterials with unique physicochemical properties have recently attracted a lot of attention since they offer a lot of potential in biomedical research. Novel generations of engineered nanostructures, also known as designed and functionalized nanomaterials, have opened up new possibilities in the applications of biomedical approaches such as biological imaging, biomolecular sensing, medical devices, drug delivery, and therapy. Polymers, natural biomolecules, or synthetic ligands can interact physically or chemically with nanomaterials to functionalize them for targeted uses. This paper reviews current research in nanotechnology, with a focus on nanomaterial functionalization for medical applications. Firstly, a brief overview of the different types of nanomaterials and the strategies for their surface functionalization is offered. Secondly, different types of functionalized nanomaterials are reviewed. Then, their potential cytotoxicity and cost-effectiveness are discussed. Finally, their use in diverse fields is examined in detail, including cancer treatment, tissue engineering, drug/gene delivery, and medical implants.

Potential Impact of Reduced Graphene Oxide Incorporated Metal Oxide Nanocomposites as Antimicrobial, and Antibiofilm Agents Against Pathogenic Microbes: Bacterial Protein Leakage Reaction Mechanism

In the current study, nanocomposites-based reduced graphene oxide (RGO) and metal oxides (AgO, NiO, and ZnO) were fabricated. The starting precursor and RGO were characterized by XRD, Raman, SEM, and HRTEM, while SEM and EDX mapping validated the synthesized nanocomposites. In addition, ZOI, MIC, antibiofilm, and growth curve were tested. The antimicrobial reaction mechanism was investigated by protein leakage assay and SEM imaging. Results revealed that all synthesized nanocomposites (RGO-AgO, RGO-NiO, and RGO-ZnO) have outstanding antimicrobial activity against pathogenic bacteria and unicellular fungi. Moreover, RGO-AgO, RGO-NiO, and RGO-ZnO nanocomposites exhibited an antibiofilm activity percentage against Staphylococcus aureus (91.72%), Candida albicans  (91.17%), and Escherichia coli (90.36%). The SEM analysis of S. aureus after RGO-AgO treatment indicated morphological differences, including the whole lysis of the outer surface supported by deformations of the bacterial cells. It was observed that the quantity of cellular protein leakage from S. aureus is directly proportional to the concentration of RGO-AgO, RGO-NiO, and RGO-ZnO nanocomposites and found to be 260.25 µg/mL, 110.55 µg/mL, and 99.90 µg/mL, respectively. The prepared nanocomposites promise to treat resistant microbes as a new strategy for managing infectious diseases.

Nanoliposomes in Cancer Therapy: Marketed Products and Current Clinical Trials

The drugs used for cancer treatment have many drawbacks, as they damage both tumor and healthy cells and, in addition, they tend to be poorly soluble drugs. Their transport in nanoparticles can solve these problems as these can release the drug into tumor tissues, as well as improve their solubility, bioavailability, and efficacy, reducing their adverse effects. This article focuses on the advantages that nanotechnology can bring to medicine, with special emphasis on nanoliposomes. For this, a review has been made of the nanoliposomal systems marketed for the treatment of cancer, as well as those that are in the research phase, highlighting the clinical trials being carried out. All marketed liposomes studied are intravenously administered, showing a reduced intensity of side-effects compared with the nonliposomal form. Doxorubicin is the active ingredient most frequently employed. Ongoing clinical trials expand the availability of liposomal medicines with new clinical indications. In conclusion, the introduction of drugs in nanoliposomes means an improvement in their efficacy and the quality of life of patients. The future focus of research could be directed to develop multifunctional targeted nanoliposomes using new anticancer drugs, different types of existing drugs, or new standardized methodologies easily translated into industrial scale.

Novel fabrication of SiO2/Ag nanocomposite by gamma irradiated Fusarium oxysporum to combat Ralstonia solanacearum

The bacterial wilt is a global destructive plant disease that initiated by the phytopathogenic Ralstonia solanacearum. This study display a novel biofabrication of silica/silver nanocomposite using Fusarium oxysporum-fermented rice husk (RH) under solid state fermentation (SSF). The biofabricated nanocomposite was characterized by XRD, UV–Vis. spectroscopy, DLS, SEM, EDX elemental mapping, and TEM analyses as well as investigated for anti-R. solanacearum activity. Response surface methodology was also processed for optimizing the biofabrication process and improving the anti-bacterial activity of the fabricated nanocomposite. Maximum suppression zone of 29.5 mm against R. solanacearum was reached at optimum RH content of 6.0 g, AgNO₃ concentration of 2.50 mM, reaction pH of 6.3, and reaction time of 2 days. The anti-R. solanacearum activity of the fabricated nanocomposite was further improved by exposing the F. oxysporum strain to a gamma irradiation dose of 200 Gy. In conclusion, RH recycling under SSF by F. oxysporum could provide an innovative, facile, non-expensive, and green approach for fabricating SiO₂/Ag nanocomposite that could be applied efficiently as an eco-friendly antibacterial agent to combat R. solanacearum in agricultural applications. Moreover, the developed method could serve as a significant platform for the designing of new nanostructures for broad applications.

Biofabricated SiO₂/Ag nanocomposite by gamma irradiated-F. oxysporum under SSF.

Statistical optimization and complete characterization of SiO₂/Ag nanocomposite.

Application in agriculture for combating the wilt causing R. solanacearum.

Study of the mechanism of mitochondrial division and mitochondrial autophagy in the male reproductive toxicity induced by nickel nanoparticles

Male reproductive health is deteriorating, and fertility is largely affected by environmental factors. This study aims to investigate the potential mechanism underlying mitochondrial division and mitochondrial autophagy in the male reproductive toxicity of nickel nanoparticles (Ni NPs). An in vivo mouse (BALB/c) model was constructed to calculate testicular organ coefficients and sperm abnormality rates, and detect serum reproductive hormones, testicular pathological morphology, and the expression of Drp1, Pink1, and Parkin proteins. Furthermore, mouse spermatogonia (GC-1 cells) were used as an in vitro model to detect cell viability, apoptosis, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP), ATP and protein expression. After treatment with an additional inhibitor, Mdivi-1, such influences were further detected to explore the possible mechanism of male reproductive toxicity induced by Ni NPs. The in vivo studies showed that compared with the control group, exposure to Ni NPs reduced the serum levels of testosterone, follicle stimulating hormone and luteinizing hormone, increased the sperm abnormality rate, widened the gaps in the seminiferous tubules of the testes, decreased the sperm count, and increased the expression of Drp1, Pink1 and Parkin proteins (all P < 0.05). The in vitro studies further confirmed that compared with the control group, Ni NPs can lead to decreased cell viability, increased apoptosis, accumulation of ROS, decreased MMP and ATP, increased expression of Drp1, Pink1, Parkin, Bax, caspase-9 and caspase-3 proteins, and decreased expression of Bcl-2, resulting in an increased value of Bax/Bcl-2. It is worth noting that such influences induced by Ni NPs were significantly reversed by the additional Mdivi-1. In conclusion, Drp1-mediated mitochondrial division and Pink1/Parkin-mediated mitochondrial autophagy play an important role in the male reproductive toxicity of Ni NPs, during which both of them form an interaction cycle and accelerate the occurrence of cell apoptosis.

Nanomaterials-Based Urinary Extracellular Vesicles Isolation and Detection for Non-invasive Auxiliary Diagnosis of Prostate Cancer

Extracellular vesicles (EVs) are natural nanoparticles secreted by cells in the body and released into the extracellular environment. They are associated with various physiological or pathological processes, and considered as carriers in intercellular information transmission, so that EVs can be used as an important marker of liquid biopsy for disease diagnosis and prognosis. EVs are widely present in various body fluids, among which, urine is easy to obtain in large amount through non-invasive methods and has a small dynamic range of proteins, so it is a good object for studying EVs. However, most of the current isolation and detection of EVs still use traditional methods, which are of low purity, time consuming, and poor efficiency; therefore, more efficient and highly selective techniques are urgently needed. Recently, inspired by the nanoscale of EVs, platforms based on nanomaterials have been innovatively explored for isolation and detection of EVs from body fluids. These newly developed nanotechnologies, with higher selectivity and sensitivity, greatly improve the precision of isolation target EVs from urine. This review focuses on the nanomaterials used in isolation and detection of urinary EVs, discusses the advantages and disadvantages between traditional methods and nanomaterials-based platforms, and presents urinary EV-derived biomarkers for prostate cancer (PCa) diagnosis. We aim to provide a reference for researchers who want to carry out studies about nanomaterial-based platforms to identify urinary EVs, and we hope to summarize the biomarkers in downstream analysis of urinary EVs for auxiliary diagnosis of PCa disease in detail.

Engineered magnetic oxides nanoparticles as efficient sorbents for wastewater remediation: a review

The rapid urbanization and industrialization is causing worldwide water pollution, calling for advanced cleaning methods. For instance, pollutant adsorption on magnetic oxides is efficient and very practical due to the easy separation from solutions by an magnetic field. Here we review the synthesis and performance of magnetic oxides such as iron oxides, spinel ferrites, and perovskite oxides for water remediation. We present structural, optical, and magnetic properties. Magnetic oxides are also promising photocatalysts for the degradation of organic pollutants. Antimicrobial activities and adsorption of heavy metals and radionucleides are also discussed.

Recent advances of chitosan-based nanoparticles for biomedical and biotechnological applications

Chitosan is a natural alkaline polysaccharide, which widely exists in marine crustaceans such as shrimp and crab, has been shown to have various biological activities. It has attracted considerable attention in biomedicine and nanomaterials fields because of its excellent properties, such as biocompatibility, biodegradability, non-toxicity and easy access. In addition, because of active hydroxyl and amino groups in chitosan molecules, different functional groups can be introduced into chitosan molecules by molecular modification or chemical modification, which extends their applications. Nanoparticles with small size and large surface area can be used as diagnostic and therapeutic tools in the biomedical field, which make it easier to understand, detect and treat human diseases. The nanomaterials based on chitosan have important applications in biomedicine, industry, pharmacy, agriculture, and other fields. This review highlights the recent advances on chitosan-based nanoparticles for antibacterial property, drug and gene delivery, cancer and hyperthermia therapy, cell imaging, restorative dentistry, wound healing, tissue engineering and other biomedical fields. The nanotechnology fields involving biosensors, water treatment, food industry and agriculture are also briefly reviewed.

Nanobioengineering: A promising approach for early detection of COVID-19

Unique pneumonia due to an unknown source emerged in December 2019 in the city of Wuhan, China. Consequently, the World Health Organization (WHO) declared this condition as a new coronavirus disease-19 also known as COVID-19 on February 11, 2020, which on March 13, 2020 was declared as a pandemic. The virus that causes COVID-19 was found to have a similar genome (80% similarity) with the previously known acute respiratory syndrome also known as SARS-CoV. The novel virus was later named Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 falls in the family of Coronaviridae which is further divided into Nidovirales and another subfamily called Orthocoronavirinae. The four generations of the coronaviruses belongs to the Orthocoronavirinae family that consists of alpha, beta, gamma and delta coronavirus which are denoted as α-CoV, β-CoV, γ-CoV, δ-CoV respectively. The α-CoV and β-CoVs are mainly known to infect mammals whereas γ-CoV and δ-CoV are generally found in birds. The β-CoVs also comprise of SARS-CoV and also include another virus that was found in the Middle East called the Middle East respiratory syndrome virus (MERS-CoV) and the cause of current pandemic SARS-CoV-2. These viruses initially cause the development of pneumonia in the patients and further development of a severe case of acute respiratory distress syndrome (ARDS) and other related symptoms that can be fatal leading to death.

Preparation and disinfection properties of graphene oxide/trichloroisocyanuric acid disinfectant

Due to the impact of the new crown epidemic in recent years, disinfectants have played an increasingly important role, so the research and development of new high-efficiency nano-disinfectants are urgent issues. In this study, graphene oxide (GO) was first prepared by the modified Hummer method. Then, the GO/trichloroisocyanuric acid (TCCA) composite was prepared by loading TCCA into GO with the blending method. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy and atomic force microscopy were used to characterize the composite. The results showed that TCCA was successfully loaded on the surface of GO or intercalated among GO layers. Next, the antibacterial performance of the composite againstEscherichia coliandStaphylococcus aureuswas tested by the 96-well plate assay. A bactericidal kinetic curve, bacterial inhibition tests, and the mechanism of bacterial inhibition were discussed. The results showed that the minimum inhibitory concentration (MIC) of the GO/TCCA composite (GO:TCCA ratio = 1:50) was 327.5μg ml^-1againstE. coliand 655μg ml^-1againstS. aureus. At the MIC, the inhibition rate of the GO/TCCA composite exceeded 99.46% againstE. coliand 99.17% againstS. aureus. The bactericidal kinetic curves indicate that the GO/TCCA composite has an excellent bactericidal effect againstE. coliandS. aureus.

Nanobiotic formulations as promising advances for combating MRSA resistance: susceptibilities and post-antibiotic effects of clindamycin, doxycycline, and linezolid

Antimicrobial activity and post-antibiotic effects (PAEs) are both important parameters in determination of the dosage regimen of antimicrobial agents. In the present study, antimicrobial activity and PAEs of clindamycin, doxycycline, linezolid, and their nanobiotic formulations were evaluated against two methicillin resistant Staphylococcus aureus clinical isolates (MRSA) encoded (MRSA-S1 and MRSA-S2). Nanobiotic formulations increased the susceptibility of MRSA isolates by 4–64 folds as compared to their conventional ones. The PAE values were determined after exposure of MRSA isolates for 1 h to 10× the MICs of the tested antibiotics. The duration of PAEs were recorded after bacterial growth in Mueller Hinton broth (MHB) free from antibiotic has been restored. The PAE values for MRSA-S1 were 2.5 h for the conventional antibiotics. However, the PAEs for nanobiotics were 4 h for both clindamycin and linezolid, while 3 h for doxycycline. For MRSA-S2, linezolid and linezolid nanobiotics PAEs were 3 h. PAEs of clindamycin and clindamycin nanobiotics were 3.75 h and 4 h, respectively. Doxycycline and doxycycline nanobiotics revealed the same PAEs patterns of 3.5 h. The findings of the current study may positively influence the pharmacodynamics of the antibiotics and consequently the dosage regimen of nanobiotics as well as on their clinical outcome.

Novel nanobiotic formulations of clindamycin, doxycycline, and linezolid were evaluated for the post-antibiotic effects against biofilm forming methicillin resistant Staphylococcus aureus (MRSA).

Role of nanostructures in allergy: Diagnostics, treatments and safety

Nanotechnology is science, engineering and technology conducted at the nanoscale, which is about 1-100 nm. It has led to the development of nanomaterials, which behave very differently from materials with larger scales and can have a wide range of applications in biomedicine. The physical and chemical properties of materials of such small compounds depend mainly on the size, shape, composition and functionalization of the system. Nanoparticles, carbon nanotubes, liposomes, polymers, dendrimers and nanogels, among others, can be nanoengineeried for controlling all parameters, including their functionalization with ligands, which provide the desired interaction with the immunological system, that is dendritic cell receptors to activate and/or modulate the response, as well as specific IgE, or effector cell receptors. However, undesired issues related to toxicity and hypersensitivity responses can also happen and would need evaluation. There are wide panels of accessible structures, and controlling their physico-chemical properties would permit obtaining safer and more efficient compounds for clinical applications goals, either in diagnosis or treatment. The application of dendrimeric antigens, nanoallergens and nanoparticles in allergy diagnosis is very promising since it can improve sensitivity by increasing specific IgE binding, mimicking carrier proteins or enhancing signal detection. Additionally, in the case of immunotherapy, glycodendrimers, liposomes, polymers and nanoparticles have shown interest, behaving as platforms of allergenic structures, adjuvants or protectors of allergen from degradation or having a depot capacity. Taken together, the application of nanotechnology to allergy shows promising facts facing important goals related to the improvement of diagnosis as well as specific immunotherapy.