Synthesis Of CuNPs Research Articles

Copper nanoparticles synthesis from Andrographis paniculata leaf extract– characterization and its application

Copper nanoparticle synthesis and characterization are now being done widely due to its broad nanotechnology research interest, especially in medical applications. The current work set out to produce copper nanoparticles(CuNPs) by employing the herb Andrographis paniculata for medicinal purposes. Andrographis paniculata leaf extract was used to make CuNPs using copper sulphate (CuSO4). For monitoring the synthesis of CuNPs, the UV-vis absorption spectra were obtained and Surface Plasmon resonance (SPR) peaks at 500nm. The X-ray diffraction (XRD) pattern reveals the average size of the crystallites is 5.876 nm. This environmentally friendly approach yields homogenous, spherical particles, as demonstrated by images of Scanning and Transmission electron microscopy (TEM and SEM). The outcomes demonstrated that leaf extract is most suited for producing CuNPs. It shows a greater zone of inhibition and inhibitory action against tested bacteria such as Bacillus cereus, Escherichia Coli, Klebsiella pneumoniae and Staphylococcus aureus, and it can be used for the inhibition of several harmful microbes. Because the synthesized CuNPs are non-toxic, environmentally benign, and suitable for usage in pharmaceutical and other fields, they can be applied in a variety of ways in future.

From cornfield to catalyst support: Eco-friendly synthesis of Cu/CuO nanoparticles, immobilization on the waste corn husk fibers, photocatalytic exploration and bioactivity evaluation

This study presents an innovative approach to eco-friendly synthesis and utilization of copper nanoparticles (CuNPs) for photocatalytic applications, employing waste corn husk fibers as sustainable catalyst support. The synthesis of CuNPs was achieved through a green synthesis method utilizing myrtle extract. Subsequently, the remarkable photocatalytic activity of the CuNPs explored (76% removal efficiency of Crystal Violet), showcased their potential in environmental remediation applications. Furthermore, the immobilization of CuNPs onto waste corn husk fibers was investigated, aiming to develop a novel composite material with enhanced catalytic performance. A distinctive approach was introduced by immobilizing CuNPs onto fibers derived from corn husks, and waste biomass material, leading to a significant enhancement in photocatalytic efficiency, surpassing 95.1%. Furthermore, bioactivity evaluation studies revealed the significant antioxidant, antidiabetic, DNA fragmentation, cell viability, antibiofilm and antimicrobial properties of CuNPs. The antioxidant ability was determined at 100 mg/L as 87.12%. The most powerful antimicrobial activity of CuNP was found as a MIC value of 8 mg/L against E. faecalis. The cell viability inhibition of CuNP was 90.05% at 20 mg/L. CuNP exhibited biofilm inhibition activity at different concentrations. The antibiofilm ability was investigated against Staphylococcus aureus compared to Pseudomonas aureginosa. While the DNA cleavage activity of CuNP observed double-strand breaks at 50 and 100 mg, complete fragmentation occurred at 200 mg concentrations. The bioactivity of the synthesized CuNPs shed light on their potential biomedical applications. The synthesized CuNPs are characterized using various analytical techniques to elucidate their structural and morphological properties. Fourier-transform infrared (FTIR) analysis provided insights into the chemical composition and surface properties of the synthesized materials. EDS analysis confirmed their successful integration into waste corn husk fibers. Overall, this interdisciplinary study highlights the potential of CuNPs immobilized on waste corn husk fibers for addressing environmental pollution, advancing sustainable technologies and paving the way for the development of efficient catalysts with diverse functionalities.

Alocasia Indica Assisted Green Synthesis of Metallic Cu Nanoparticles for Enhanced Antimicrobial Activities

In the past several years, the widespread utility of copper nanoparticles (CuNPs) has spurred global interest in streamlining synthesis methodologies. Notably, this study introduces an environmentally conscious strategy for synthesizing CuNPs using the extract of Alocasia indica. Employing a chemical reduction process, A. indica, abundant in phenolics and flavonoids, acts as a potent reducing agent. The nanoparticles (NPs) synthesized by A. indica have been carefully characterized by Ultraviolet–Visible (UV–Viz) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD) analysis and antimicrobial analysis. UV testing, spanning wave length, elucidates light absorption attributed to the newly formed CuNPs by showcasing a surface plasmonic resonance peak at 204 nm. The evolution of the FTIR spectrum of the produced CuNPs confirms the presence of diverse biomolecules. TEM delineates the synthesis of irregularly shaped particles. Elemental composition analysis via EDX identifies the presence of various elements, including C, O, Al, Cl, K and Cu, with detailed insights into their mass percentages, standard deviations, atom percentages and characteristic X-ray energy levels. The successful synthesis of CuNPs is validated by XRD, which reveals characteristic copper peaks at 2[Formula: see text] = [Formula: see text], [Formula: see text] and [Formula: see text]. The synthesized NP showed 98.99% inhibition against Staphylococcus aureus and 99.99% inhibition against Escherichia coli. This research presents an easy, economical and ecologically friendly process for producing CuNPs utilizing A. indica extracts.

From agro-food waste to nanoparticles: green synthesis of copper nanoparticles with lignin peroxidase enzyme produced by Anoxybacillus rupiensis using peanut shells.

This study presents a novel approach for the eco-friendly green synthesis of copper nanoparticles (Cu NPs) using enzymatic mediation which is an environmentally benign alternative to conventional methods, offering control over particle size and shape. Anoxybacillus rupiensis BS1 thermophilic bacterium was isolated from Erzurum's Pasinler hot spring and lignin peroxidase enzyme production conditions (incubation time 96h, 40g/L shell amount, pH 8.5, 150rpm, and 60°C temperature) were used in the production of peroxidase enzyme using peanut waste which has been optimized. The characterization of the synthesized Cu NPs was performed using various analytical techniques, including UV-vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM), confirming the successful production of stable and well-defined nanoparticles. Furthermore, the biological activities of the synthesized Cu NPs were explored, revealing their potential for antimicrobial applications. The antibacterial efficacy of the Cu NPs against some pathogens such as Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus pyogenes, and Bacillus cereus was examined. It was determined that Cu NPs were effective on all pathogens and had the highest effectiveness against the S. pyogenes pathogen (19.0mm). This study not only presents an innovative and sustainable approach for the synthesis of Cu NPs but also highlights the multifaceted biological activities of these nanoparticles, opening avenues for diverse applications in the fields of medicine, agriculture, and environmental remediation. The utilization of peanut shell wastes as a substrate for enzyme production adds value to agricultural by-products, contributing to the development of a circular and sustainable economy.

Biogenic synthesis of copper nanoparticle using Impatiens chinensis L: insights into antimicrobial, antioxidant and anticancer activity

Impatiens chinensis plant is a various medicinal properties and use in the field of biomedicine in several decades. In present of the study, successfully green synthesized copper nanoparticles (CuNPs) using the leaf extract of I. chinensis. The synthesized CuNPs were thoroughly characterized using various techniques such as UV, FTIR, XRD, and SEM with EDAX, TEM, particle size and Zeta potential analysis. The UV–Vis analysis confirmed the successful synthesis of CuNPs, as indicated by absorbance peak at 313 nm. FTIR spectra revealed the different functional groups and molecular bonding interactions of the CuNPs, while XRD analysis unveiled the crystalline nature of the NPs. SEM imaging confirmed the spherical structure of the CuNPs and EDAX confirmed the Copper (Z), Oxygen (O) and CuL (Cl) elements. TEM imaging confirming the spherical shape and identifying the SAED pattern. Moreover, the particle size analysis the size of 63.1 nm identified and the zeta potential range of -27.1 mv confirmed their stability. To evaluate the antibacterial activity of different pathogenic bacteria using various zone of inhibitions. CuNPs antioxidant activity, as evidenced by DPPH (53.20%), ABTS (52.37%) and Hydroxyl scavenging assays (51.02%). The evaluate CuNPs for their potential anti-cancer properties in MCF-7 cell lines, showing (65.34%) inhibition. Overall, the findings of this study green-synthesized CuNPs as multifunctional agents with antibacterial, antioxidant and anticancer properties. These nanoparticles hold potential for biomedical applications, providing sustainable solutions for a range of health related challenges.

The role of biomaterial constituents of Jasminum sambac (L.) Aiton leaves in copper nanoparticles synthesis and evaluates their activities as anti-breast cancer and antibacterial agents

Copper nanoparticles (CuNPs) were prepared using Iraqi Jasminum sambac (L.) Aiton. Substances identified by GC-MS to know pathway mechanism CuNPs synthesis. Characterization of CuNPs was done by UV-VIS at 420 nm, functional groups disclosed through FTIR, XRD broad chart in small CuNPs. Morphology and size of CuNPs were spherical in shape with an average size of less than 10 nm via TEM and FESEM, DLS appointed at 180.7 nm, good polydispersity at 0.24, and Z-potential analysis at −11.7 refer to stability. CuNPs against (Staphylococcus aureus) and (Escherichia coli) were actively compared with classical antibiotic drugs. An anticancer study that demonstrated in vitro cytotoxicity by MTT assay IC50 at 372 µg/mL against MCF-7, emphasized microscopic images of destroyed cells after exposure to CuNPs. Genotoxicity of cancer cells treating it as a signal to break down the DNA of targeted cancer cells (comet assay). Additionally, diminishing count DNA population of cells via flow cytometry.

Biosynthesis of Copper Nanoparticles using an Extract of the root of Asparagus racemosus: Basic Synthesis, Antimicrobial, and Anti-oxidant Potentials

Copper nanoparticles (CuNPs) have emerged as a promising alternative due to their unique antimicrobial properties. The synthesis of CuNPs using Asparagus racemosus, commonly known as Shatavari, offers a sustainable and environmentally friendly approach to producing nanomaterials. Moreover, the resulting CuNPs have been found to possess excellent antibacterial, and antioxidant properties, which further expands their potential applications in medicine and environmental remediation. In this article, we discussed the in vitro characterization of the CuNPs. In vitro studies revealed that CuNPs have the potential for biomedical applications and as a base nanomaterial for the construction of drug delivery and targeting vehicles.

Green Synthesis of Copper Nanoparticles Using Sargassum spp. for Electrochemical Reduction of CO2.

This study presents a green method of producing copper nanoparticles (CuNPs) using aqueous extracts from Sargassum spp. as reducing, stabilizing, and capping agents. The CuNPs created using this algae-based method are not hazardous, they are eco-friendly, and less toxic than their chemically synthesized counterparts. The XRD characterization of the CuNPs revealed the presence of Cu and CuO, with a crystallite size ranging from 13 to 17 nm. Following this, the CuNPs were supported onto a carbon substrate, also derived from Sargassum spp. (biochar CSKPH). The CuNPs in biochar (CuNPs-CSKPH) did not appear in the XRD diffractograms, but the SEM-EDS results showed that they accounted for 36 % of the copper weight. The voltamperometric study of CuNps-CSKPH in acid media validated the presence of Cu and the amount was determined to be 2.58 μg. The catalytic activity of CuNPs-CSKPH was analyzed for the electrochemical reduction of CO2. The use of Sargassum spp. has great potential to tackle two environmental problems simultaneously, by using it as raw material for the synthesis of activated biochar as support, as well as the synthesis of CuNPs, and secondly, by using it as a sustainable material for the electrochemical conversion of CO2.

Electrochemical aptasensor based on DNA-templated copper nanoparticles and RecJf exonuclease-assisted target recycling for lipopolysaccharide detection.

An electrochemical aptasensor for detecting lipopolysaccharides (LPS) was fabricated based on DNA-templated copper nanoparticles (DNA-CuNPs) and RecJf exonuclease-assisted target recycling. The DNA-CuNPs were synthesized on a double-stranded DNA template generated through the hybridization of the LPS aptamer and its complementary chain (cDNA). In the absence of LPS, the CuNPs were synthesized on DNA double-strands, and a strong readout corresponding to the CuNPs was achieved at 0.10 V (vs. SCE). In the presence of LPS, the fabricated aptamer could detach from the DNA double-strand to form a complex with LPS, disrupting the template for the synthesis of CuNPs on the electrode. Meanwhile, RecJf exonuclease could hydrolyze the cDNA together with this single-stranded aptamer, releasing the LPS for the next round of aptamer binding, thereby enabling target recycling amplification. As a result, the electrochemical signal decreased and could be used to indicate the LPS content. The fabricated electrochemical aptasensor exhibited an extensive dynamic working range of 0.01 pg mL-1 to 100 ng mL-1, and its detection limit was 6.8 fg mL-1. The aptasensor also exhibited high selectivity and excellent reproducibility. Moreover, the proposed aptasensor could be used in practical applications for the detection of LPS in human serum samples.

Synthesis and characterization of chitosan-copper nanocomposites and their catalytic properties for 4-nitrophenol reduction

Biopolymer-based copper nanoparticles (CuNPs) have become an area of significant interest due to their wide-ranging applications in a variety of fields. However, there remains a challenge in tailoring their morphologies and improving their properties. In this study, CuNPs were synthesized via wet chemical reduction using sodium hypophosphite monohydrate (NaH2PO2·H2O), l-ascorbic acid and chitosan. The effect of different synthesis conditions, including reaction pH, temperature, time, concentration of NaH2PO2·H2O, l-ascorbic acid and chitosan, as well as the deacetylation degree (DD) of chitosan, on the synthesis of CuNPs was investigated. The synthesized CuNPs were characterized by various analytical techniques. The catalytic properties of synthesized CuNPs were investigated for the reduction of 4-nitrophenol (4-NP) in the presence of sodium borohydride. The synthesis-morphology-catalytic activity relationship of CuNPs was discussed. The results suggested that the morphology of CuNPs could be adjusted by controlling the synthesis conditions. Chitosan DD significantly impacts the morphology of the synthesized CuNPs. As the chitosan DD decreased from 91.8 % to 52.3 %, the average particle size of synthesized CuNPs decreased from 43.9 ± 10.6 to 17.7 ± 5.9 nm and the shape changed from anisotropy to near-sphere. CuNPs synthesized using low DD (53.2 %) chitosan (CuNPs-N3) demonstrated the highest 4-NP conversion rate of 99.1 % and reaction rate constant of 0.3540 min−1. CuNPs-N3 was thermodynamically and kinetically more feasible than CuNPs synthesized with high DD chitosan. These findings provide important insights for further designing and developing hierarchical nanostructured CuNPs catalysts for broader applications.

Nano-sized copper particles: Chemical synthesis, characterization, and their size and surface charge dependent antibacterial potential

Copper nanoparticles (Cu NPs) were studied extensively for their antibacterial potential compared to other metal NPs in the recent past. However, comparative analysis of different reducing and stabilizing agents in the synthesis of Cu NPs and their possible effect in antibacterial activity is not clearly stated. Herein, authors report the synthesis of Cu NPs using three reducing and stabilizing agents such as sodium borohydride (SBH), tri-sodium citrate (TSC), and oxalic acid (OA), individually. The as-synthesized Cu NPs were studied for their optical, physicochemical, and morphological properties followed by their role (shape and surface charge of NPs) in defining its antibacterial potential. Cu NPs@SBH showed moderate to good antibacterial activity against Escherichia coli (15.23 ± 0.65 mm), Lactococcus lactis (20.65 ± 0.96 mm), Micrococcus luteus (21.48 ± 1.12 mm), Bacillus sp. (14.33 ± 0.52 mm), and Pseudomonas putida (19.58 ± 0.43 mm). Cu NPs@SBH had average particle size of 46.8 nm and surface charge of −42.1 mV. The results indicate that both size and surface charge played a vital role in the antibacterial activity of Cu NPs.

Wound healing activity of green synthesized copper nanoparticles through cell proliferation-migration, antimicrobial effects, and nitric oxide triggering

The present experimental study was designed to evaluate the in vitro wound healing and anti-inflammatory effects of copper nanoparticles (CuNPs) green synthesized by the methanol extract Ferula macrecolea Boiss, as a plant with various pharmacological effects such as anti-inflammatory, and antimicrobial effects in traditional and modern medicine. The precipitation approach was used to green synthesis of CuNPs through mixing the methanol and copper sulfate solution. Cell viability and fibroblast proliferation assay were performed by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. The migration abilities of fibroblasts cells were evaluated using a cell scratch in vitro wound healing assay. Effects of CuNPs on iNOS expression genes were also performed by Real-time PCR. In vitro antibacterial susceptibility test of CuNPs was carried out according to the standards protocol of the National Committee for Clinical Laboratory Standards (NCCLS). The analysis of SEM revealed that the green synthesized CNP exhibited a globular shape with a size ranging from 15-90 nm; while their majority were at 40-60 nm. The results of the MTT assay showed that the calculated CC50 value of green synthesized CuNPs was 236.3 μg/mL. The optimum concentrations of the CuNPs which were selected based on the 50% cytotoxic concentration (CC50) value; whereas dose-dependently increased the proliferation of fibroblast cells. The CuNPs dose-dependently increased the rate of wound closure after 16 and 24 h. The results of the Real-Time PCR showed that CuNPs causes an upregulation in expression level of gene of nitric oxide synthesis (iNOS) in RAW 264.7 cells. CuNPs showed the promising antimicrobial effects against S. aureus, S. epidermidis and Ps. aeruginosa. The present study showed the high potency of CuNPs green synthesized by F. macrecolea for wound healing through their antimicrobial, proliferation of fibroblast cells, and provoking iNOS.

Novel approach for green synthesis of Cu-NPs using Centella asiatica leaf extract, assisted by BiFeO3 nanoparticles for electrochemical glucose- and fructose-sensing applications

This research explored the structural, optical, morphological, and electrochemical properties of the green-synthesized copper metal nanoparticles using Centella asiatica leaf extract and assisted by perovskite-structured bismuth ferrite nanomaterial (Cu/BFO NPs, namely CBO NPs). The structural confirmation of the synthesized CBO NPs was done by X-ray diffraction method, through which the crystallite size was determined to be 52 nm, derived through the Debye–Scherrer equation. The optical absorption band was presented at around 271 and 690 nm. A high-resolution scanning electron microscope revealed the spherical morphology of the synthesized CBO NPs. The electrochemical sugar-sensing activities of CBO NPs and the anti-interference study were performed through cyclic voltammetry and chronoamperometry techniques, respectively. The sensitivity value of the CBO NPs for glucose sugar was found to be 425 μA mM−1 cm−2. The synthesized CBO NPs were suitable for glucose sugar sensor applications.

ELECTROSYNTHESIS OF CATALYTIC ACTIVE Pd-Cu AND Pd-Au BIMETALLIC NANOPARTICLES NANOCOMPOSITES WITH POLY(N-VINYLPYRROLIDONE) AND NANOCELLULOSE

It was investigated the preparation in an undivided cell of Pd-Cu and Pd-Au bimetallic nanoparticles (NPs) by methylviologen (MV2+) -mediated electrochemical reduction of equimolar amounts of Cu(II), Pd(II) and Au(I) in the presence of poly(N-vinylpyrrolidone) (PVP) and nanocellulose (NC) at controlled potential of generating MV cation radical in aqueous medium at room temperature. Electrosyntheses were performed by sequential or joint reduction of metal ions by passing a theoretical amount of electricity. When Pd(II) ions are added to CuNPs, as well as Au(I) ions are added to PdNPs, a galvanic replacement process is observed, namely oxidation of Cu0 by Pd(II) and Pd0 Au(I) ions. The results of complete reduction are nanocomposites of mainly spherical MNPs, dispersed in the solution bulk, and stabilized by PVP on the surface of the NC. In the sequential synthesis of CuNPs and then PdNPs, the nanocomposite is presented as Cu2O nanoroses coated with fine PdNPs. Nanocomposites of Pd NPs with Cu2O or Au shows the mainly formation of spherical particles with the size of 4 to 50 nm depending on the production method. X-ray powder diffraction (XRD) data of nanocomposites confirm the formation of a mixture of PdNPs (0.8 - 10 nm) with large gold crystallites (until 24 nm), as well as the oxidation of CuNPs to cuprite (Cu2O). The size of metal crystallites and copper oxide varies in the range from 0.8 to 24 nm. In the test reaction of p-nitrophenol reduction with sodium borohydride in aqueous medium, all tested nanocomposites showed time-increasing catalytic activity. When Cu is added to Pd, the catalytic reduction reaction is maintained, while the addition of Au to Pd decreases the catalytic activity of PdNPs by an order of magnitude.

Studying the Potential of Copper Nanoparticles Synthesized from Staphylococcus aureus against Drug-Resistant Bacteria

Copper nanoparticles (CuNPs) have gained a lot of interest due to their tendency to combat various bacterial strains, making them potential candidates against antibiotic resistant bacteria. Green synthesis of CuNPs eradicates the potential drawbacks of other traditional methods such as high cost, toxic chemicals and adverse conditions. The objectives of current study include the preparation of CuNPs from the culture supernatant of Staphylococcus aureus and the analysis of antibacterial potential of prepared CuNPs. The synthesis of CuNPs from the culture supernatant of Staphylococcus aureus was carried out under various optimization conditions including pH, temperature, incubation time, and concentration of salt. This research study focuses on the preparation of fine and well defined CuNPs by the reduction of Cu2+ ions using the culture supernatant of clinical isolate of Staphylococcus aureus as the feasible and cost effective method. The prepared nanoparticles were characterized through various techniques including Ultraviolet Visible Spectrophotometry, Dynamic Light Scattering and Scanning electron microscopy. The prepared copper nanoparticles were studied for their antibacterial potential by the Agar Well Method against drug resistant and drug sensitive bacteria. The surface plasmon resonance of copper nanoparticles was maximum around the visible range wavelength of 380 nm which is the characteristic absorbance peak of copper nanoparticles while the dynamic light scattering analysis recorded the maximum percentage intensity of particle size distribution around 295 nm. SEM analysis showed the amorphous nature of particles with no distinct size and shape. CuNPs showed significant antibacterial potential against drug resistant Salmonella typhimurium with 29mm zone of inhibition and against drug sensitive Bacillus subtillis with 25mm zone of inhibition. The antibacterial potential of copper nanoparticles was found to be appreciable against drug resistant Salmonella typhimurium, Staphylococcus epidermis and Staphylococcus aureus.

Green Synthesis of Copper Nanoparticles Using Citrullus colocynthis Peel Extract and Antibacterial Activity for Biomedical Applications

A novel and green method was developed to synthesise copper nanoparticles (CuNPs) using Citrullus colocynthis peel extract as a sustainable source. The study is the first to utilise this extract for the environmentally safe and economically efficient synthesis of CuNPs. The impact of experimental parameters, including the copper sulfate concentration, extract volume, reaction time, and temperature, on the synthetic procedure was thoroughly investigated. The as-prepared CuNPs were characterised using HRTEM, FESEM, XRD, EDX, UV–vis spectrophotometry, and FTIR spectroscopy. The CuNPs exhibited a spherical morphology with an average particle size of 9 nm, and the calculated d-spacing values were measured at 0.257 nm. Furthermore, the XRD analysis revealed characteristic diffraction peaks at 2θ angles of 44.56°, 56.1°, and 71.4°. The UV–Vis absorption spectra of the CuNPs displayed a surface plasmon resonance (SPR) peak at 335 nm, corresponding to an energy band gap of 3.47 eV. Further, the FTIR spectra confirmed the interaction between copper and the biomolecules present in the extract, providing evidence of the significant role played by organic compounds in the capping process. The as-prepared CuNPs exhibited strong antibacterial activity against both gram-negative (P. aeruginosa and E. coli) and gram-positive (S. aureus and S. epidermidis) bacteria.

Plasmonic CuS 2D nanosheets through biologically and environmentally benign template free one-pot synthesis

Our research unveils a novel and eco-friendly technique for the synthesis of emerging two-dimensional Copper Sulfide (CuS) nanosheets through the sulfidation of surface-modified Cu NPs. These fabricated CuS nanosheets exhibit captivating properties such as fluorescence and surface plasmon resonance (SPR) within the near-infrared (NIR) spectrum, rendering them as remarkable candidates for transformative applications in bioimaging and medical sensing.The structural and optical characterization of the material were carried out, and the morphological characterization using SEM and HRTEM shows the formation of 2D CuS as exfoliated long sheets. The investigation projects a simple and cost-effective method to produce 2D Copper Sulfide (CuS) nanosheets. It is formed through a two-step process, including the synthesis of Cu NPs, and transformation of these colloidal Cu NPs into CuS nanosheets through sulfidation. It is found that the concentrations of sulfur and the surface modifying agents like curcumin and ascorbic acid influence nucleation and promote 2D growth of the nanosheets. The effect of sulfur concentration, pH, and surface modifying agents on SPR properties of the Cu NPs were investigated, and the results are presented here. Additionally, our findings indicate that both seed-mediated syntheses and ligand-assisted surface modification leads to the growth of these CuS nanosheets. The cellular studies show that sulfidation reduces the cellular cytotoxicity of Cu NPs. The sample also exhibits excellent stability and biocompatibility, and it is proved to be a promising candidate for photocatalytic, sensing, and biomedical applications, and hence emerges as a multifunctional 2D material.

Aspartic Acid-Based Nano-Copper Induces Resilience in Zea mays to Applied Lead Stress Via Conserving Photosynthetic Pigments and Triggering the Antioxidant Biosystem

Heavy metal stress, including lead, adversely affects the growth and yield of several economically important crops, leading to food challenges and significant economic losses. Ameliorating plant responses to various environmental stresses is one of the promising areas of research for sustainable agriculture. In this study, we evaluated the effect of aspartic acid-functionalized copper nanoparticles on the photosynthetic efficiency and antioxidation system of maize plants under Pb toxicity. The ion reduction method was employed for the synthesis of CuNPs, using ascorbic acid as the reducing agent and aspartic acid as the surface functionalizing agent. Isolated experiments under laboratory and field conditions were performed using a randomized complete block design (RCBD). Seeds primed in water, 1.0, 5.0, and 10 µg/mL of Asp-CuNPs were sown under 0, 500, and 1000 mg/L Pb stress in laboratory conditions, while primed seeds along with foliar-applied Asp-CuNP plants were grown in a field under applied Pb stress, and the obtained data were statistically analyzed using TWANOVA. The laboratory experiment shows that Asp-CuNPs act both as a plant growth regulator (PGR) and plant growth inhibitor (PGI), depending upon their concentration, whereby Asp-CuNPs act as a PGR at a concentration of 1 µg/mL ≤ X ≤10 µg/mL. The field experiment confirms that seed priming and foliar spraying with Asp-CuNPs activate embryos and enhance plant growth in a dose-dependent manner. In addition, Asp-CuNPs (10 µg/mL) significantly increase chlorophyll content to 0.87 mg/g from 0.53 mg/g (untreated) when plants were exposed to Pb toxicity at 1000 mg/kg of soil. It is noteworthy that Asp-CuNPs induce resilience to Pb toxicity (1000 mg/kg of soil) in plants by reducing its root absorption from 3.68 mg/kg (0 µg/mL Asp-CuNPs) to 1.72 mg/kg with the application of 10 µg/mL Asp-CuNPs. Additionally, histochemical analyses with NBT and hydrogen peroxide revealed that ROS accretion in plants treated with Asp-CuNPs declined because of the augmentation of antioxidant enzyme (POD, SOD, APOX, etc.) activities under Pb toxicity. Our findings suggest that amino acid-functionalized copper nanoparticles regulate plant defensive mechanisms related to lead tolerance, which is a promising approach for the induction of resistivity to heavy metal stress.

Fabrication of CuNPs Using Schiff Base Ligand and Their Catalytic Reduction of Pharmaceutical Drugs, Fluorescence Selective Detection of Cd2+, Antimicrobial, and Antioxidant Activities.

Here, we have approached the synthesis of copper nanoparticles (CuNPs) Schiff base (5-trifluoromethoxy-2-(((2chloro-5-(methyl)phenyl)imino)methyl)phenol)). The synthesized CuNPs were characterized by UV-vis spectroscopy, PL, FTIR, powder XRD, and TEM analysis. From the UV-vis absorption spectroscopy, an absorption peak was observed at 585 nm. As a result of the powder XRD and TEM studies, spherical particle sizes ranged between 4 and 10 nm. FT-IR analysis confirmed the presence of functional groups ‒OH, C=C, -C=N-, and C‒H triggers the synthesis of CuNPs. Further, the catalytic property of the CuNPs were revealed by the degradation of pharmaceutical drugs such as Capecitabine (CAP) and Ciprofloxacin (CIP) in 90 min of reaction time in the presence of NaBH4. The reaction kinetics followed pseudo-first-order with k-values (rate constant) 0.248 min-1 and 0.307 min-1. In addition, the synthesized CuNPs have exhibited selective sensing detection of Cd2+ metal ions in different range of concentration (10-100 µM) by spectrofluorometrically with the limit of detection (LOD) is 0.0284 nM and limit of quantification (LOQ) is 0.0586 nM. The CuNPs revealed significant antioxidant activities against DPPH as a common free radical at 50 µg/mL with 71.24% of scavenging activity. The maximum antimicrobial potential and zone of inhibition of P. Aeruginosa is 17.25±0.8 mm and A. niger is 12.1 mm by using CuNPs.

Green Synthesis of Copper Nanoparticles by Using Plant Extracts and their Biomedical Applications – An Extensive Review

Abstract: In recent years, the green synthesis of different metal nanoparticles has become a substantial technique for the synthesis of different essential nanoparticles and their potential applications in technological, industrial along with biomedical fields. Among the several essential nanoparticles, copper nanoparticles (CuNPs) have attracted enormous attention for their wide range of applications like the production of gas sensors, solar cells, high-temperature superconductors as well as drug delivery materials and catalysis owing to its distinctive optical, electrical, dielectric, imaging and catalytic, etc. properties. Herein, in this review, our aim is to find out the recent progress of synthesis, as well as different optical and structural characterizations of green, synthesized CuNPs along with their broadspectrum biomedical applications, mainly antibacterial, antifungal, antiviral and anticancer as well as the future perspective of research trends in the green synthesis of CuNPs. CuNPs have been synthesized by different researchers using three methods, namely, physical, chemical, and biological. In this review, the eco-friendly, efficient and low cost different established biological/green synthesis methods of CuNPs using different plant extracts like leaves, flowers, fruits, seeds, latex, etc., as capping and reducing agents have been briefly discussed, along with reaction conditions together with their optical as well as structural analysis. Effects of different parameters on the green synthesis of CuNPs like the presence of phytochemicals and confirmation of phytochemicals, temperature, pH, etc., are elucidated. Studies of the antibacterial activity of biomolecules capped CuNPs by different researchers against both Gram-positive and Gram-negative bacterial strains along with minimum inhibitory concentration (MIC) values have been summarized. Furthermore, antifungal and antiviral effects of green synthesized CuNPs studied by different researchers are mentioned with minimum inhibitory concentration (MIC) values. The anticancer activity of green synthesized CuNPs against different cancer cells studied by different researchers is summarized with correlation sizes of CuNPs on anticancer activity. The review also focuses on in vivo applications of green synthesized CuNPs along with clinical trails. Furthermore, an emphasis is given to the effectiveness of CuNPs in combating COVID-19.