Synthesis, biomedical applications, and toxicity of CuO nanoparticles.

Versatile nature of copper oxide nanoparticles (CuO NPs) has made them an imperative nanomaterial being employed in nanomedicine. Various physical, chemical, and biological methodologies are in use for the preparation of CuO NPs. The physicochemical and biological properties of CuO NPs are primarily affected by their method of fabrication; therefore, selectivity of a synthetic technique is immensely important that makes these NPs appropriate for a specific biomedical application. The deliberate use of CuO NPs in biomedicine questions their biocompatible nature. For this reason, the present review has been designed to focus on the approaches employed for the synthesis of CuO NPs; their biomedical applications highlighting antimicrobial, anticancer, and antioxidant studies; and most importantly, the in vitro and in vivo toxicity associated with these NPs. This comprehensive overview of CuO NPs is unique and novel as it emphasizes on biomedical applications of CuO NPs along with its toxicological assessments which would be useful in providing core knowledge to researchers working in these domains for planning and conducting futuristic studies. KEY POINTS: • The recent methods for fabrication of CuO nanoparticles have been discussed with emphasis on green synthesis methods for different biomedical approaches. • Antibacterial, antioxidant, anticancer, antiparasitic, antidiabetic, and antiviral properties of CuO nanoparticles have been explained. • In vitro and in vivo toxicological studies of CuO nanoparticles exploited along with their respective mechanisms.

Significance of Capping Agents of Colloidal Nanoparticles from the Perspective of Drug and Gene Delivery, Bioimaging, and Biosensing: An Insight.

The over-growth and coagulation of nanoparticles is prevented using capping agents by the production of stearic effect that plays a pivotal role in stabilizing the interface. This strategy of coating the nanoparticles' surface with capping agents is an emerging trend in assembling multipurpose nanoparticles that is beneficial for improving their physicochemical and biological behavior. The enhancement of reactivity and negligible toxicity is the outcome. In this review article, an attempt has been made to introduce the significance of different capping agents in the preparation of nanoparticles. Most importantly, we have highlighted the recent progress, existing roadblocks, and upcoming opportunities of using surface modified nanoparticles in nanomedicine from the drug and gene delivery, bioimaging, and biosensing perspectives.

Comparative toxicity of green and chemically synthesized CuO NPs during pregnancy and lactation in rats and offspring: Part I -hepatotoxicity.

Widespread applications of nanomaterials in food and health sciences have inevitable toxicological outcomes. Among nanomaterials, copper oxide nanoparticles (CuO NPs) are commonly used in all fields due to its distinctive characteristics. The study was designed to investigate the comparative hepatotoxic effect of green (GNPs) and chemically synthesized (CNPs) CuO NPs on spargue-dawely rats and their offspring. NPs (50 and 100 mg/kg) were orally administered to rats twice a week starting before mating. After birth the parents were continued dosing while pups were only on mother feed. Antioxidant, lipid peroxidation, genotoxicity, and histology were performed on liver tissue. In addition serum biochemistry of parents and offspring was also performed. The levels of catalase, peroxidase, and glutathione were significantly lowered only in CNPs treated parents while lipid peroxidation level was increased in these groups. Maximum genotoxicity (2.3%) in terms of percent tail DNA was observed in parent rats administered with high CNPs dose while other groups did not exhibit significant variation in genetoxic parameters. Gender and dose dependent effects were observed on liver function tests especially ALP and ALT in parents however no obvious differences were observed in offspring. Furthermore, dose dependent dilation and congestion of sinusoids was observed on CNPs administration. In GNPs treated rats and offspring histological alterations were observed. The study concludes that chemically synthesized CuO NPs exhibit dose dependent toxic effects on liver as compared to green synthesized CuO NPs. Furthermore lactation does not play significant role in the hepatotoxicity of offspring though minor oxidative stress was observed only on CNPs administration. The study also shows that pharmacological application of green synthesized NPs can be accomplished due to their biocompatible nature.

Role of capping agents in the application of nanoparticles in biomedicine and environmental remediation: recent trends and future prospects.

Capping agents are of utmost importance as stabilizers that inhibit the over-growth of nanoparticles and prevent their aggregation/coagulation in colloidal synthesis. The capping ligands stabilize the interface where nanoparticles interact with their medium of preparation. Specific structural features of nanoparticles are attributed to capping on their surface. These stabilizing agents play a key role in altering the biological activities and environmental perspective. Stearic effects of capping agents adsorbed on the surface of nanoparticles are responsible for such changing physico-chemical and biological characteristics. Firstly, this novel review article introduces few frequently used capping agents in the fabrication of nanoparticles. Next, recent advancements in biomedicine and environmental remediation approaches of capped nanoparticles have been elaborated. Lastly, future directions of the huge impact of capping agents on the biological environment have been summarized.

Green and Chemical Syntheses of CdO NPs: A Comparative Study for Yield Attributes, Biological Characteristics, and Toxicity Concerns.

Metallic nanoparticles (NPs) have enormous applications due to their remarkable physical and chemical properties. The synthesis of NPs has been a matter of concern because chemical methods are toxic. On the contrary, biological methods are considered eco-friendly. To compare the toxicity and the environment-friendly nature of the synthesis methodologies, cadmium NPs were synthesized through chemical (Ch) (co-precipitation) and biological (plant extracts as reducing agent) methods. Cadmium nitrate was reduced with NaOH, while in the biological method, the Cd ions were reduced by Artemisia scoparia (As) and Cannabis sativa (Cs) extracts. X-ray diffraction (XRD) analysis confirmed the pure single-phase cubic structure of green and chemically synthesized CdO NPs except As-CdO NPs that were crystalline cum amorphous in nature. The size of nanoparticles was 84 nm (Cs-CdO NPs) and 42.2 nm (Ch-CdO NPs). The scanning electron microscope (SEM) images exhibited an irregular disklike morphology of nanoparticles that agglomerated more in the case of green synthesis. The antioxidant and antimicrobial potential of NPs revealed that chemically synthesized NPs have better antimicrobial capability, while the antioxidative activities were better for green-synthesized NPs. However, the low yield, high ion disassociation, and waste (unreacted metal) production in the green synthesis of CdO NPs increase the risk of contamination to biosphere. Both types of NPs did not affect the seed germination of Dodonaea viscosa. However, chemically synthesized NPs were less toxic on plant morphological response. The study concludes that the chemically synthesized CdO NPs have better morphology, significant antimicrobial activity, and less toxicity to plant species compared to green-synthesized NPs. Moreover, during the green synthesis, unreacted metals are drained, which causes contamination to the ecosystem.

Biomarker selection and imaging design in cancer: A link with biochemical pathways for imminent engineering.

Malignant cells reprogram metabolic pathways to meet the demands of growth and proliferation. These altered manners of metabolism are now identified as hallmarks of cancer. Studies have revealed tumor cells alter specific pathways such as glycolysis, fatty acid synthesis and amino acid synthesis to support their proliferation. In this review, we provide a theoretical framework to understand metabolic reprogramming and the mechanisms accompanying distorted metabolism to tumor progression. How these alterations will be assisting in cancer diagnostics and advances in standard techniques in marker identification and imagining are also discussed.

Toxicity of copper oxide nanoparticles: a review study.

Copper oxide nanoparticles (CuO NPs) use has exponentially increased in various applications (such as industrial catalyst, gas sensors, electronic materials, biomedicines, environmental remediation) due to their flexible properties, i.e. large surface area to volume ratio. These broad applications, however, have increased human exposure and thus the potential risk related to their short- and long-term toxicity. Their release in environment has drawn considerable attention which has become an eminent area of research and development. To understand the toxicological impact of CuO NPs, this review summarises the in-vitro and in-vivo toxicity of CuO NPs subjected to species (bacterial, algae, fish, rats, human cell lines) used for toxicological hazard assessment. The key factors that influence the toxicity of CuO NPs such as particle shape, size, surface functionalisation, time-dose interaction and animal and cell models are elaborated. The literature evidences that the CuO NPs exposure to the living systems results in reactive oxygen species generation, oxidative stress, inflammation, cytotoxicity, genotoxicity and immunotoxicity. However, the physio-chemical characteristics of CuO NPs, concentration, mode of exposure, animal model and assessment characteristics are the main perspectives that define toxicology of CuO NPs.

Anticancer and antibacterial potential of Rhus punjabensis and CuO nanoparticles.

The present study reports ecofriendly synthesis of CuO nanoparticles (NPs) using an extract of Rhus punjabensis as a reducing agent. NPs structural and composition analysis are evaluated by X-rays diffraction (XRD), Fourier transform infrared, Energy dispersive spectroscopy, Scanning electron microscopy, Transmission electron microscopy, and Thermal analysis. The NPs have pure single phase monoclinic geometry with spherical structure and high stability toward heat and with average particle size of about 36.6 and 31.27 nm calculated by XRD and SEM, respectively. NPs are tested for antibacterial, protein kinase (PK) inhibition, SRB cytotoxic, and NF-κB activities. Antibacterial activity is observed against B. subtilis and E. coli. Significant PK and SRB cytotoxic activity is observed with some NF-κB inhibition. NPs IC50 values against HL-60 and PC-3 prostate cancer cells are 1.82 ± 1.22 and 19.25 ± 1.55 µg/mL. The results encourage further studies for antibacterial and anticancer drug development of NPs using animal models.

Green Bio-Assisted Synthesis, Characterization and Biological Evaluation of Biocompatible ZnO NPs Synthesized from Different Tissues of Milk Thistle (Silybum marianum).

The purpose of the current study was green synthesis of ZnO-nanoparticles (NPs) from different tissues of Silybum marianum (L.) Gaernt. (i.e., seeds, wild plant, in vitro derived plantlets and callus cultures) followed by extensive characterization and evaluation of their biological potency. ZnO-NPs thus synthesized were subjected to characterization using standard techniques such as XRD, FTIR and SEM. Thermal stability of synthesized NPs was also evaluated using thermo-gravimetric analysis. Highly stable crystalline NPs with size ranging between 30.8 and 46.0 nm were obtained from different tissues of S. marianum. These NPs have revealed a wide range of biological applications showing antioxidant, moderate α-amylase inhibitor, antibacterial and cytotoxic potencies. The highest antibacterial activity (20 ± 0.98 mm) was shown by seed extract-mediated ZnO NPs against Staphylococcus aureus (ATCC-6538). Seed extract-mediated ZnO NPs also showed the most potent antioxidant activity (27.7 ± 0.9 µgAAE/mg, 23.8 ± 0.7 µgAAE/mg and 12.7 ± 1.9% total antioxidant capacity (TAC), total reducing power (TRP) and DPPH-free radical scavenging assay (FRSA), respectively). All of the synthesized ZnO NPs also showed cytotoxic activity against the hepato-cellular carcinoma (HepG2) human cells. Interestingly, these ZnO NPs were also highly biocompatible, as evidenced by the brine shrimp lethality and human red blood cells hemolytic assays. Among all of the NPs synthesized and used, the effect of seed extract-mediated NPs was found to be most promising for future applications.

Synthesis, characterization and biological activities of monometallic and bimetallic nanoparticles using Mirabilis jalapa leaf extract.

Monometallic ZnO and Ag nanoparticles (NPs) and bimetallic ZnO/Ag NPs were synthesized using leaves extract of Mirabilis jalapa. XRD analysis confirmed the crystalline nature of NPs with size range from 19.3 to 67.4 nm for bimetallic, and 12.9 and 32.8 nm for monometallic NPs. SEM images reveal varying shapes of the monometallic (needle like and spherical for ZnO and Ag, respectively) and bimetallic (plates, sheets, and spherical) NPs depending upon concentration of salts used. Biological characterization reveals that both mono and bi metallic nanoparticles demonstrate free radical scavenging, total antioxidant, and reducing power potentials. Phenolic and flavonoid like properties of NPs were also observed might be due to presence of different functional groups on the particles surface. Bimetallic NPs displayed astonishing antibacterial (up to 25 mm zone of inhibition) and antileishmanial properties. The results suggest that bimetallic ZnO/Ag nanoparticles hold greater potential then monometallic against bacteria and Leishmania. Other biomedical applications also varied depending upon concentration of precursors. Furthermore, ratio of salt concentrations used for synthesis of bimetallic NPs affect morphological and biochemical characteristics of NPs.

CeO2 nanoparticles synthesized through green chemistry are biocompatible: In vitro and in vivo assessment.

Widespread use of cerium oxide (CeO2 ) nanoparticles (NPs) is found in almost all areas of research due to their distinctive properties. CeO2 NPs synthesized via green chemistry have been characterized for antioxidant, phytochemical, and biological potential. Physical characterization through scanning electron microscopy, XRD, and TGA showed that the NPs are circular in shape, 20-25 nm in size, and stable in a wide range of temperature. NPs display significant antioxidant (32.7% free radical scavenging activity) and antileishmanial (IC50 48 µg mL-1 ) properties. In vitro toxicity tested against lymphocytes verified that NPs are biocompatible (99.38% viability of lymphocytes at 2.5 µg mL-1 ). In vivo toxicity experiments showed no harmful effects on rat serum chemistry and histology of various organs and did not even change the concentration of antioxidative enzymes, total protein contents, lipid peroxidation, and nitrosative stress. These observations are in line with the statement that plant-based synthesis of CeO2 NPs lessens or nullifies in vitro and in vivo toxicity and hence CeO2 NPs are regarded as a safe and biocompatible material to be used in drug delivery.

Low-temperature synthesis of hierarchical structures of copper oxide and their superior biological activity.

In this work, the authors report a facile low-temperature wet-chemical route to prepare morphology-tailored hierarchical structures (HS) of copper oxide. The preparation of copper oxide collides was carried out using varying concentrations of copper acetate and a reducing agent at a constant temperature of 50°C. The prepared HS of CuO were characterised by powdered X-rays diffraction that indicates phase pure having monoclinic structures. The morphology was further confirmed by field-emission scanning electron microscope. It reveals a difference in shape and size of copper oxide HS by changing the concentration of reactants. In order to evaluate the effect of H2O2 on CuO NPs, the prepared CuO are modified by treatment with H2O2. In general trend, CuOH2O2 collide showed enhanced protein kinase inhibition, antibacterial (maximum zone 16.34 mm against Staphylococcus aureus) and antifungal activities in comparison to unmodified CuO collides. These results reveal that CuO HS exhibit antimicrobial properties and can be used as a potential candidate in pharmaceutical industries.

Nanomaterials as nanocarriers: a critical assessment why these are multi-chore vanquisher in breast cancer treatment.

Breast cancer is a group of diseases with various subtypes and leads to high mortality throughout the globe. Various conventional techniques are in practice to cure breast cancer but these techniques are linked with various shortcomings. Mostly these treatments are not site directed and cause toxicity towards normal cells. In order to overcome these issues, we need smart system that can deliver anticancer drugs to specific sites. Targeted drug delivery can be achieved via passive or active drug delivery using nanocarriers. This mode of drug delivery is more effective against breast cancer and may help in the reduction of mortality rate. Potentially used nanocarriers for targeted drug delivery belong to organic and inorganic molecules. Various FDA approved nano products are in use to cure breast cancer. However, body's defense system is main limitation for potential use of nano systems. However, this can be overcome by surface modification of nanocarriers. In this review, breast cancer and its types, targeted drug delivery and nanocarriers used to cure breast cancer are discussed. By progressing nanotechnology, we will be able to fight against this life threatening issue and serve the humanity, which is the basic aim of scientific knowledge.

Kinnow peel extract as a reducing and capping agent for the fabrication of silver NPs and their biological applications.

An effective approach used for the synthesis of silver nanoparticles (AgNPs) through green chemistry by using Kinnow peel extract as a reducing and capping agent is presented. Two different approaches, diluted and concentrated peel extracts, were used for the synthesis of AgNPs. Ultraviolet-visible spectroscopy exhibits characteristic absorption peaks at 425 and 400 nm for nanoparticles (NPs) synthesised by diluted and concentrated extracts, respectively. The X-ray diffraction analysis of nanofabricated silver exhibited a pure face centred cubic structure of 27.4 and 18.1 nm sizes calculated by using Scherrer equation. Scanning electron microscopy analysis showed a uniform morphology of synthesised NPs. Significant antioxidant, phytochemical and antibacterial assays show that both AgNPs can be effectively used in biomedical applications. Furthermore, the use of citrus peel for the synthesis of NPs can be an effective tool in waste management.

Green synthesis of silver nanoparticles from grape and tomato juices and evaluation of biological activities.

The biosynthesis of silver nanoparticles (AgNPs) is substantial for its application in lots of fields. Tomato and grape fruit juices were used as a reducing and capping agents for the biosynthesis of AgNPs. Ultraviolet spectroscopic analysis offered peaks in the range of 396‒420 nm that indicate the production of AgNPs. Fourier transform infrared spectroscopy analysis revealed attachment of different functional groups with Ag ion in both tomato and grape fruit extracts NPs. The X‒ray diffraction analysis confirmed that the synthesised AgNPs have a face centred cubic confirmation. Scanning electron microscopy confirms the size of NPs that varies from 10 to 30 nm. The DPPH free radical scavenging assay, total antioxidant capacity, reducing power assay, total flavonoid contents and total phenolic contents determination confirmed that synthesised AgNPs are potent antioxidant agents; can be used as an effective scavenger of free radicals. Biosynthesised AgNPs also showed good antibacterial activity against Pseudomonas septica, Staphylococcus aureus, Micrococcus luteus, Enterobacter aerogenes, Bacillus subtilis and Salmonella typhi. Protein kinase inhibition activity showed a clear zone which indicates anticancerous potential of biosynthesised AgNPs. The efficacious bioactivities indicate that the tomato and grape derived AgNPs can be used efficiently in pharmaceutical and medical industries.

Management of citrus waste by switching in the production of nanocellulose.

Citrus fruit processing industries produce a vast quantity of waste materials as peel and pulp that are not handled properly. In present study, waste generated from citrus has been used for extraction of cellulose and nanocellulose. The aggregated cellulose, derived after alkaline treatment, was acid hydrolysed; resulted in reduction of the size of cellulose fibre. The cellulose showed amorphous structure revealed by X-ray diffraction analysis. Scanning electron microscopy analysis explained densely packed structure of nanocellulose. High magnification revealed break points in cellulose fibre due to acidic treatment; looked like carbon nanotubes. The simple solubility test demonstrated that different solvents had different effects on the dissolution of nanocellulose. The study reveals that citrus peel is also a good candidate of cellulose that can be utilised for different applications.

Antimicrobial potential of green synthesized CeO2 nanoparticles from Olea europaea leaf extract.

This article reports the green fabrication of cerium oxide nanoparticles (CeO2 NPs) using Olea europaea leaf extract and their applications as effective antimicrobial agents. O. europaea leaf extract functions as a chelating agent for reduction of cerium nitrate. The resulting CeO2 NPs exhibit pure single-face cubic structure, which is examined by X-ray diffraction, with a uniform spherical shape and a mean size 24 nm observed through scanning electron microscopy and transmission electron microscopy. Ultraviolet-visible spectroscopy confirms the characteristic absorption peak of CeO2 NPs at 315 nm. Fourier transform infrared spectroscopy reflects stretching frequencies at 459 cm-1, showing utilization of natural components for the production of NPs. Thermal gravimetric analysis predicts the successful capping of CeO2 NPs by bioactive molecules present in the plant extract. The antimicrobial studies show significant zone of inhibition against bacterial and fungal strains. The higher activities shown by the green synthesized NPs than the plant extract lead to the conclusion that they can be effectively used in biomedical application. Furthermore, reduction of cerium salt by plant extract will reduce environmental impact over chemical synthesis.