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Nanotechnology has emerged as a promising field with the potential to revolutionize agriculture, particularly in enhancing plant defense mechanisms. Nanoparticles (NPs) are instrumental in plant defense priming, where plants are pre-exposed to controlled levels of stress to heighten their alertness and responsiveness to subsequent stressors. This process improves overall plant performance by enabling quicker and more effective responses to secondary stimuli. This review explores the application of NPs as priming agents, utilizing their unique physicochemical properties to bolster plants' innate defense mechanisms. It discusses key findings in NP-based plant defense priming, including various NP types such as metallic, metal oxide, and carbon-based NPs. The review also investigates the intricate mechanisms by which NPs interact with plants, including uptake, translocation, and their effects on plant physiology, morphology, and molecular processes. Additionally, the review examines how NPs can enhance plant responses to a range of stressors, from pathogen attacks and herbivore infestations to environmental stresses. It also discusses NPs' ability to improve plants' tolerance to abiotic stresses like drought, salinity, and heavy metals. Safety and regulatory aspects of NP use in agriculture are thoroughly addressed, emphasizing responsible and ethical deployment for environmental and human health safety. By harnessing the potential of NPs, this approach shows promise in reducing crop losses, increasing yields, and enhancing global food security while minimizing the environmental impact of traditional agricultural practices. The review concludes by emphasizing the importance of ongoing research to optimize NP formulations, dosages, and delivery methods for practical application in diverse agricultural settings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Carbon nanotubes (CNTs) are emerging pollutants of occupational and environmental health concern. While toxicological mechanisms of CNTs are emerging, there is paucity of information on their modulatory effects on susceptibility to infections. Here, we investigated cellular and molecular events underlying the effect of multi-walled CNT (MWCNT) exposure on susceptibility to Streptococcus pneumoniae infection in our 28-day sub-chronic exposure mouse model. Data indicated reduced phagocytic function in alveolar macrophages (AMs) from MWCNT-exposed lungs evidenced by lower pathogen uptake in 1-h infection assay. At 24-h post-infection, intracellular pathogen count in exposed AMs showed 2.5 times higher net increase (2-fold in vehicle- versus 5-fold in MWCNT-treated), indicating a greater rate of intracellular multiplication and/or survival due to MWCNT exposure. AMs from MWCNT-exposed lungs exhibited downregulation of pathogen-uptake receptors CD163, Phosphatidyl-serine receptor (Ptdsr), and Macrophage scavenger receptors class A type 1 (Msr1) and type 2 (MSr2). In whole lung, MWCNT exposure shifted the macrophage polarization state towards the immunosuppressive phenotype M2b and increased the CD11c + dendritic cell population required to activate the adaptive immune response. Notably, the MWCNT pre-exposure dysregulated T-cell immunity, evidenced by diminished CD4 and Th17 response, and exacerbated Th1 and Treg responses (skewed Th17/Treg ratio), thereby favoring the pneumococcal infection. Overall, these findings indicated that MWCNT exposure compromises both innate and adaptive immunity leading to diminished host lung defense against pneumonia infection. To our knowledge, this is the first report on an immunomodulatory role of CNT pre-exposure on pneumococcal infection susceptibility due to dysregulation of both innate and adaptive immunity targets., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Aim: Emergence of vancomycin (Van) resistance, and usage of its higher dose and short half-life are posing a serious concern. Slow and sustained release of Van using a nanodelivery system may overcome these problems. Materials & methods: Arginine-α,β-dehydrophenylalanine (RΔF) was synthesized using solution-phase synthesis which self-assembled into nanospheres. Van was entrapped in the nanoparticles (NPs). In vitro and in vivo efficacy of Van-RΔF was determined using broth microdilution and the mouse thigh infection model, respectively. Results & conclusion: Van-RΔF NPs efficiently inhibited bacterial growth ( Staphylococcus aureus ), while Van alone showed limited growth inhibition in in vitro . Intravenous administration of Van-RΔF in mice with bacterial thigh infection showed enhanced efficacy (double) compared with Van alone, which indicates its high potential for further development.

Cerium oxide nanoparticles (CeNPs) exhibit excellent in vitro and in vivo antioxidant properties, determined by the redox switching of surface cerium ions between their two oxidation states (Ce 3+ and Ce 4+ ). It is known that ligands such as triethyl phosphite (TEP) can tune the redox behavior of CeNPs and change their biological enzyme-mimetic activities; however, the corresponding mechanism for such a behavior is completely unknown. Herein, we have studied the effect of TEP in promoting the SOD-enzyme-like activity in CeNPs with high and low Ce 3+ /Ce 4+ ratio, which were synthesized by wet chemical and thermal hydrolysis methods, respectively, and incubated with varying concentrations of TEP. X-ray diffraction, UV-visible, photoluminescence, X-ray photoelectron spectroscopy, and Raman spectroscopy combined with DFT calculations were used to investigate the interaction of TEP on the surface of CeNPs. We observed a clear correlation between TEP concentration and the formation of surface oxygen vacancies. XPS analysis confirmed the increase in Ce 3+ concentration after interaction with TEP. Moreover, we show that TEP's influence depends on the surface Ce 3+ /Ce 4+ ratio. The superoxide dismutase-, catalase-, and oxidase-like activities of CeNPs with high Ce 3+ /Ce 4+ ratio are not affected by TEP interaction, whereas catalase- and oxidase-like activities of CeNPs with low Ce 3+ /Ce 4+ ratio decrease and the SOD-like activity is found to increase upon incubation with different concentrations of TEP. We also demonstrate that TEP interaction does not affect the regeneration of the CeNP surface, while the DFT calculations show that TEP facilitates the formation of defects on the surface of stoichiometric cerium oxide by reducing the oxygen vacancy formation energy. CeNPs with low Ce 3+ /Ce 4+ ratio incubated with TEP also exhibited good antibacterial activity as compared to the CeNPs or TEP alone.

Cancer is the leading cause of human disease and death worldwide, accounting for 7.6 million deaths per year and projected to reach 13.1 million by 2030. Many phytochemicals included in traditional medicine have been utilized in the management of cancer. Conventional chemotherapy is generally known to be the most effective treatment of metastatic cancer but these cancerous cells might grow resistant to numerous anticancer drugs over time that resulting in treatment failure. This review tried to portray the advancement in the anticancer and chemopreventive effects of several phytochemicals and some of its members encapsulated in the nano-based delivery system of the drug. It comprises the issue associated with limited use of each phytoconstituents in human cancer treatment are discussed, and the benefits of entrapment into nanocarriers are evaluated in terms of drug loading efficiency, nanocarrier size, release profile of the drug, and in vitro and/or in vivo research and treatment testing, such as cytotoxicity assays and cell inhibition/viability., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The biological enzyme-mimetic activity of cerium oxide nanoparticles (CeNPs) is well known to scavenge the reactive oxygen and nitrogen species in cell culture and animal models, imparting protection from the deleterious effects of oxidative and nitrosative stress. The superoxide dismutase (SOD)- and catalase-mimicking activity of CeNPs is reported to be controlled by the oxidation state of the surface "Ce" ions, where a high ratio of Ce 3+/4+ or Ce 4+/3+ has been considered for the displayed SOD and catalase-like activity, respectively. However, the redox behavior of CeNPs can be controlled by certain ligands that could offer changes in their enzyme-mimetic properties. Therefore, in this work, we have studied the enzyme-mimetic activities of CeNPs under the influence of polyoxometalates [phosphomolybdic acid (PMA) and phosphotungstic acid (PTA)], which are electron-dense molecules displaying quick and reversible multielectron redox reactions. Results revealed that the interaction of PMA with CeNPs results in the inhibition of the SOD-like activity; however, it has no impact on the catalase-like activity. Contrary to this, the interaction of PTA with CeNPs improved the SOD as well as catalase-like activities of CeNPs (3+), which generally do not exhibit catalase activity in the bare form. Although CeNPs (3+) did not show any peroxidase-like activity, CeNPs (4+) showed excellent activity, which was enhanced after the interaction with polyoxometalates. Further, the autoregeneration ability of CeNPs was found to be intact even after PTA or PMA interaction; however, the full catalytic activity was observed in the case of PTA but partially with PMA.

The catalytic performance of gold (Au) decorated cerium oxide nanoparticles (nanoceria) can be potentially crucial because such a defined arrangement of multiple materials may provide improved chemical and biological catalytic activities. In this work, we have utilized a highly localized approach to reduce Au nanoparticles (AuNPs) on the nanoceria-phosphotungstate composite's surface. Phosphotungstic acid (PTA) bound on nanoceria's surface acts as a UV-light dependent redox molecule that specifically reduces AuNPs. The mechanistic study demonstrates that PTA* molecules outstanding electron transfer ability leads to an excellent improvement in the catalytic performance of nanoceria-PTA*-AuNPs composite. Nanoceria-PTA*-AuNPs showed better and faster degradation of 4-nitrophenol than either nanoceria or PTA*-AuNPs. The developed nanoceria-PTA*-AuNPs exhibited efficient (>80 % in 5 min) conversion of 4-NP into 4-AP at room temperature and neutral pH. Additionally, the nanoceria-PTA*-AuNPs also showed improved peroxidase enzyme-like activity than the corresponding control samples. The observed catalytic activity could be due to the rapid electron transfer from nanoceria to AuNPs, where the metal nanoparticle acts as an electron sink, mediated by PTA*. Nanoceria-PTA*-AuNPs showed ∼ 2-fold better catalytic oxidation of peroxidase substrate than PTA*-AuNPs. The reported nanoceria-PTA*-AuNPs nanocomposites are expected to display improved biological enzyme-like activities, photocatalysis, and other biomedical applications., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Cerium oxide nanoparticles have been shown to mimic oxidoreductase enzymes by catalyzing the decomposition of organic substrates and reactive oxygen species. This mimicry can be found in superoxide radicals and hydrogen peroxides, which are harmful molecules produced in oxidative stress-associated diseases. Despite the fact that nanoparticle functionalization is mandatory in the context of nanomedicine, the influence of polymer coatings on their enzyme-like catalytic activity is poorly understood. In this work, six polymer-coated cerium oxide nanoparticles are prepared by the association of 7.8 nm cerium oxide cores with two poly(sodium acrylate) and four poly(ethylene glycol) (PEG)-grafted copolymers with different terminal or anchoring end groups, such as phosphonic acids. The superoxide dismutase-, catalase-, peroxidase-, and oxidase-like catalytic activities of the coated nanoparticles were systematically studied. It is shown that the polymer coatings do not affect the superoxide dismutase-like, impair the catalase-like and oxidase-like, and surprisingly improves peroxidase-like catalytic activities of cerium oxide nanoparticles. It is also demonstrated that the particles coated with the PEG-grafted copolymers perform better than the poly(acrylic acid)-coated ones as oxidoreductase-like enzymes, a result that confirms the benefit of having phosphonic acids as anchoring groups at the particle surface.

Cervical cancer is common among women with a recurrence rate of 35% despite surgery, radiation, and chemotherapy. Patients receiving chemotherapy or radiotherapy routinely experience several side effects including toxicity, non-targeted damage of tissues, hair loss, neurotoxicity, multidrug resistance (MDR), nausea, anemia and neutropenia. Phytochemicals can interfere with almost every stage of carcinogenesis to prevent cancer development. Many natural compounds are known to activate/deactivate multiple redox-sensitive transcription factors that modulate tumor signaling pathways. Polyphenols have been found to be promising agents against cervical cancer. However, applications of phytochemicals as a therapeutic drug are limited due to low oral bioavailability, poor aqueous solubility and requirement of high doses. Nano-sized phytochemicals (NPCs) are promising anti-cancer agents as they are required in minute quantities which lowers overall treatment costs. Several phytochemicals, including quercetin, lycopene, leutin, curcumin, green tea polyphenols and others have been packaged as nanoparticles and proven to be useful in nano-chemoprevention and nano-chemotherapy. Nanoparticles have high biocompatibility, biodegradability and stability in biological environment. Nano-scale drug delivery systems are excellent source for enhanced drug specificity, improved absorption rates, reduced drug degradation and systemic toxicity. The present review discusses current knowledge in the involvement of phytochemical nanoparticles in cervical cancer therapy over conventional chemotherapy., (Copyright © 2020. Published by Elsevier B.V.)

Introduction : From a biopharmaceutical standpoint, the skin is recognized as an interesting route for drug delivery. In general, small molecules are able to penetrate the stratum corneum , the outermost layer of the skin. In contrast, the delivery of larger molecules, such as peptides and proteins, remains a challenge. Nanoparticles have been exploited not only to enhance skin penetration of drugs but also to expand the range of molecules to be clinically used. Areas covered : This review focus on Solid lipid nanoparticles (SLN) and Nanostructured lipid carriers (NLC) for skin administration. We discuss the selection criteria for lipids, surfactants, and surface modifiers commonly in use in SLN/NLC, their production techniques, and the range of drugs loaded in these lipid nanoparticles for the treatment of skin disorders. Expert opinion : Depending on the lipid and surfactant composition, different nanoparticle morphologies can be generated. Both SLN and NLC are composed of lipids that resemble those of the skin and sebum, which contribute to their enhanced biocompatibility, with limited toxicological risk. SLN and NLC can be loaded with very chemically different drugs, may provide a tunable release profile, can be produced in a sterilized environment, and be scaled-up without the need for organic solvents.

Natural products from medicinal plants have always attracted a lot of attention due to their diverse and interesting therapeutic properties. We have employed the principles of green chemistry involving isomerization, coupling and condensation reaction to synthesize a class of compounds derived from eugenol, a naturally occurring bioactive phytophenol. The compounds were characterized structurally by 1 H-, 13 C-NMR, FT-IR spectroscopy and mass spectrometry analysis. The purity of compounds was detected by HPLC. The synthesized compounds exhibited anti-cancer activity. A 10-12-fold enhancement in efficiency of drug molecules (~ 1 µM) was observed when delivered with graphene oxide (GO) as a nanovehicle. Our data suggest cell death via apoptosis in a dose-dependent manner due to increase in calcium levels in specific cancer cell lines. Interestingly, the benzoxazine derivatives of eugenol with GO nanoparticle exhibited enhanced therapeutic potential in cancer cells. In addition to anti-cancer effect, we also observed significant role of these derivatives on parasite suggesting its multi-pharmacological capability.

The nanoparticles of haemoglobin (HbNPs) were prepared by desolvation method and characterized by transmission electron microscopy (TEM),UV-vis spectroscopy, Fourier transformation infra red (FTIR) spectroscopy and X-ray diffraction (XRD) and atomic force microscopy (AFM). Protein profile of HbNPs was also studied by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). An amperometric acrylamide biosensor was constructed by immobilizing covalently HbNPs onto polycrystalline Au electrode. The Au electrode was characterized by scanning electron microscopy (SEM) and electrochemical impedance spectra (EIS) before and after immobilization of HbNPs. The biosensor showed optimum current response within 2s at 0.26V, pH 5.0 at room temperature (20°C). The biosensor measured the acrylamide concentration in processed foods. The working range of biosensor was 0.1nm-100mM with a limit of detection (LOD) as low as 0.1nM. The biosensor measured acrylamide concentration in various processed foods such as biscuits, bread, potato crisps, "kurkure", nuts and fried cereals. The analytical recovery of added acrylamide in aqueous extract of food at 5 and 10mM was 99% and 98% respectively. Within-and between-batch, co-efficient of variations were 3.85% and 4.67% respectively. The structural analogs of acrylamide such as acrylic acid and propionic acid had practically no interference on the biosensor., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Enzymes are fundamental biocatalysts, which regulate various metabolic reactions. They exhibit high substrate specificity, sensitivity, and exceptional catalytic activity under ideal conditions and, hence, have been used as industrial catalysts. Enzyme nanoparticles have attracted the scientific community as they can be used for environment protection, biochemical engineering, and biomedicine. It is necessary to understand the nature of enzyme nanoparticles interactions with their analyte. Various types of enzyme/protein nanoparticles have been immobilized onto a matrix (electrode or membrane) for the fabrication of biosensors. Among the various nanoparticles and nanomaterials, organic nanoparticles have received more attention due to their fascinating properties. Therefore, the future research should be focused to develop advanced biosensors based on enzyme nanoparticles that could be used for early diagnosis and management of chronic diseases. This chapter explains various enzyme nanoparticles-based biosensors, such as GOX, HRP, uricase, cholesterol oxidase, hemoglobin, and their biomedical applications., (© 2018 Elsevier Inc. All rights reserved.)

The nanoparticles (NPs) of hemoglobin (Hb) were prepared by desolvation method and characterized by transmission electron microscopy (TEM), UV spectroscopy and Fourier-transform IR (FTIR) spectroscopy. An amperometric H 2 O 2 biosensor was constructed by immobilizing HbNPs covalently on to a polycrystalline Au electrode (AuE). HbNPs/AuE were characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) before and after immobilization of HbNPs. The HbNPs/AuE showed optimum response within 2.5 s at pH 6.5 in 0.1 M sodium phosphate buffer (PB) containing 100 μM H 2 O 2 at 30°C, when operated at -0.2 V against Ag/AgCl. The HbNPs/AuE exhibited V max of 5.161 ± 0.1 μA cm -2 with apparent Michaelis-Menten constant ( K m ) of 0.1 ± 0.01 mM. The biosensor showed lower detection limit (1.0 μM), high sensitivity (129 ± 0.25 μA cm -2 mM -1 ) and wider linear range (1.0-1200 μM) for H 2 O 2 as compared with earlier biosensors. The analytical recoveries of added H 2 O 2 in serum (0.5 and 1.0 μM) were 97.77 and 98.01% respectively, within and between batch coefficients of variation (CV) were 3.16 and 3.36% respectively. There was a good correlation between sera H 2 O 2 values obtained by standard enzymic colorimetric method and the present biosensor (correlation coefficient, R 2 =0.99). The biosensor measured H 2 O 2 level in sera of apparently healthy subjects and persons suffering from diabetes type II. The HbNPs/AuE lost 10% of its initial activity after 90 days of regular use, when stored dry at 4°C., (© 2017 The Author(s).)

Applications of nanotechnology in medicine and cancer are becoming increasingly popular. Common nanomaterials and devices applicable in cancer medicine are classifiable as liposomes, polymeric-micelles, dendrimers, nano-cantilevers, carbon nanotubes, quantum dots, magnetic-nanoparticles, gold nanoparticles (AuNPs) and certain miscellaneous nanoparticles. Here, we present review of the structure, function and utilities of the various approved, under trial and pretrial nanodevices applicable in the cancer care and medicine. The liposomes are phospholipid-vesicles made use in carrying drugs to the target site minimizing the bio-distribution toxicity and a number of such theranostics have been approved for clinical practice. Newly worked out liposomes and polymeric micelles are under the trail phases for nano-therapeutic utility. A multifunctional dendrimer conjugate with imaging, targeting and drug molecules of paclitaxel has been recently synthesized for cancer theranostic applications. Nano-cantilever based assays are likely going to replace the conventions methods of chemical pathological investigations. Carbon nanotubes are emerging for utility in regenerative and cancer medicine. Quantum dots hold great promise for the micro-metastasis and intra-operative tumor imaging. Important applications of magnetic nanoparticles are in the cardiac stents, photodynamic therapy and liver metastasis imaging. The AuNPs have been employed for cell imaging, computed tomography and cancer therapy. Besides these categories, miscellaneous other nanoparticles are being discovered for utility in the cancer diagnosis and disease management. However, the use of nanoparticles should be cautious since the toxic effects of nanoparticles are not well-known. The use of nanoparticles in the clinical practice and their toxicity profile require further extensive research.

Here we review the scope of nanotechnology in Medicine and human cancer. The imaging and therapy agents can be co-delivered by same nanoparticle for integrated molecular diagnosis, therapy, and follow-up of cancer or 'cancer theranostics' is implying multimodal use of nanoparticles in cancer care. Nanoparticles are used for passive targeting and in conjugation with ligands for active targeting, to have optimum concentrations of imaging and therapeutic agents in the tumor cells specifically, sparing normal tissue from unwanted side effects. Potential utility of nanoparticles in the nano biosensors, nano fluorescent tag imaging, nano tumor mapping, nano gene profiling, nano molecular delivery, nano chemo-radio therapy, nano thermotherapy, nano photodynamic therapy, etc., is tending to revolutionize medicine particularly personalized cancer care and laboratory. Nanoparticle induced oxidative stress based inflammation reported by few studies; in lung, liver and brain required further investigations.