Green Synthesis and Characterization of Copper Nanoparticles Using Fortunella margarita Leaves

The use of biomaterials in the synthesis of nanoparticles is one of the most up-to-date focuses in modern nanotechnologies and nanosciences. More and more research on green methods of producing metal oxide nanoparticles (NP) is taking place, with the goal to overcome the possible dangers of toxic chemicals for a safe and innocuous environment. In this study, we synthesized copper nanoparticles (CuNPs) using Fortunella margarita leaves’ extract, which reflects its novelty in the field of nanosciences. The visual observation of a color change from dark green to bluish green clearly shows the instant and spontaneous formation of CuNPs when the phytochemicals of F. margarita come in contact with Cu+2 ions. The synthesis of CuNPs was carried out at different conditions, including pH, temperature, concentration ratio and time, and were characterized with UV-Vis absorption spectra, scanning electron microscope (SEM) and X-ray diffraction (XRD). The UV-Vis analysis reveals the surface plasmon resonance property (SPR) of CuNPs, showing a characteristic absorption peak at 679 nm, while SEM reveals the spherical but agglomerated shape of CuNPs of the size within the range of 51.26–56.66 nm.

A Novel Biological Approach to Copper Nanoparticles Synthesis: Characterization and its Application Against Phytopathogenic Fungi

In nanotechnology, fungi have been identified as excellent candidates for the synthesis of nanoparticles, thus presenting a cleaner alternative to produce new materials with a wide range of potential applications in biomedicine and industry. In this respect, A novel biological approach Penicillium olsonii have demonstrated excellent synthesis capacity to produce copper nanoparticles (CuNPs). Their properties were determined by ultraviolet-visible (UV-Vis) absorption spectrum, Fourier transform infrared spectroscopy (FT-IR), and Scanning Electron Microscopy (SEM) images. UV-Vis spectra with characteristic absorption peak was observed at 565nm. Biomolecules mediating the synthesis and stabilizing the nanobactericides was studied with FTIR that showed different functional groups. SEM investigations confirmed that size of CuNPs were varied from 6-26 nm. The antifungal activity of CuNPs was evaluated by testing against three phytopathogenic fungi including Fusarium oxysporum, Fusarium solani and Curvularia curvulatat with growth inhibition 86.25, 32.92 and 68.42%, respectively at 200ppm. F. oxysporum was more affected by CuNPs followed by C. curvulata and F. solani. The present work demonstrated that it is possible to perform the biogenic synthesis of CuNPs using P. olsonii as appropriate fungicide.

Physicochemical Characterization of an Exopolysaccharide Produced by Lipomyces sp. and Investigation of Rheological and Interfacial Behavior

The present study aimed to evaluate the rheological and interfacial behaviors of a novel microbial exopolysaccharide fermented by L. starkeyi (LSEP). The structure of LSEP was measured by LC-MS, 1H and 13C NMR spectra, and FT-IR. Results showed that the monosaccharide composition of LSEP was D-mannose (8.53%), D-glucose (79.25%), D-galactose (7.15%), and L-arabinose (5.07%); there existed the anomeric proton of α-configuration and the anomeric carbon of α- and β-configuration; there appeared the characteristic absorption peak of the phosphate ester bond. The molecular weight of LSEP was 401.8 kDa. The water holding capacity (WHC, 2.10 g/g) and oil holding capacity (OHC, 12.89 g/g) were also evaluated. The results of rheological properties showed that the aqueous solution of LSEP was a non-Newtonian fluid, exhibiting the shear-thinning characteristics. The adsorption of LSEP can reduce the interfacial tension (11.64 mN/m) well and form an elastic interface layer at the MCT–water interface. Such functional properties make LSEP a good candidate for use as thickener, gelling agent, and emulsifier to form long-term emulsions for food, pharmaceutical, and cosmetic products.

Manganese-Doped Carbon Dots Via Inner Filter Effect for the Sensitive Detection of Tetracycline in Poultry Meat Samples

In this study, a rapid and sensitive analytical method has been developed to detect tetracycline hydrochloride (TC) using manganese-doped carbon dots (Mn-CDs) prepared by one-step hydrothermal procedure using 1-(2-pyridinylazo)-2-naohthalenol (PAN) and MnCl2 as precursor reagents. The obtained Mn-CDs showed an ultraviolet emission at 360 nm with an excitation wavelength of 300 nm. TC has a strong characteristic absorption peak at 356 nm, which has a large spectral overlap with the emission band of the Mn-CDs. The fluorescence intensity (FI) of Mn-CDs at 360 nm is linearly quenched within the TC concentration range of 0.1-200 µM. The developed assay for the detection of TC was based on an inner filter effect (IFE) mechanism and is rapid, sensitive, and was successfully applied for the determination of TC in different poultry meat samples with satisfactory results.

The preparation of modified polyamide clay nanocomposite/recycled maleic anhydride polyamide 6 and blending with low density polyethylene for film blowing application

Generally, polyamide cannot be used as film blowing material because of its unsuitable properties. In this study, polyamide 6 clay nanocomposite (cPA) and styrene maleic anhydride copolymer (SMA) were mixed in various ratios for the preparation of modified polyamide 6 clay nanocomposite SxcPAy resins by reactive extrusion. The S1cPA14 resin was blended with recycled maleic anhydride polyamide (rPA) to form the (S1cPA14)x rPAy resins. Finally, they were mixed with LDPE in 1:9 ratio to afford (SxcPAy)1LDPE9 and ((S1cPA14)x rPAy)1LDPE9 resins, respectively, followed by film blowing and the analyses of the physicochemical properties of resins. The FTIR spectrum illustrated that the C=O symmetric and asymmetric absorption fingerprint peaks in the anhydride (-OC-O-CO-) group of SMA disappeared and the new characteristic absorption peak of-CO-N-CO- of imides was observed. The anhydride functional group of SMA underwent reactive extrusion with the terminal amino group of cPA to generate the imides structure. The thermal properties showed that the glass transition temperature and crystallinity of SxcPAy and (S1cPA14)x rPAy resins increased with increasing SMA and S1cPA14 contents. The Tg (85.4.0°C) of (S1cPA14)12 rPA1 resin were enhanced significantly, with 30°C higher than cPA. In terms of tensile mechanical properties, S1cPA14 test pieces demonstrated the highest Young’s modulus and tensile strength. After mixing with LDPE, the tensile mechanical properties of (SxcPAy)1LDPE9 and ((S1cPA14)x rPAy)1LDPE9 resins and films were both higher than that of LDPE. ((S1cPA14)12 rPA1)1LDPE9 film shown the best tensile properties and barrier performance compared with other films due to the optimal rPA content could assisted SMA as a better compatibilizer to improve the dispersion and compatibility of cPA in HDPE. It was worth noting that (SxcPAy)1LDPE9 and ((S1cPA14)x rPAy)1LDPE9 resins were formed by film blowing at the processing temperature of 140°C followed by successful preparation of the film.

Interplay between Perovskite Magic-Sized Clusters and Amino Lead Halide Molecular Clusters

Recent progress has been made on the synthesis and characterization of metal halide perovskite magic-sized clusters (PMSCs) with ABX3 composition (A=CH3NH3+ or Cs+, B=Pb2+, and X=Cl−, Br-, or I-). However, their mechanism of growth and structure is still not well understood. In our effort to understand their structure and growth, we discovered that a new species can be formed without the CH3NH3+ component, which we name as molecular clusters (MCs). Specifically, CH3NH3PbBr3 PMSCs, with a characteristic absorption peak at 424 nm, are synthesized using PbBr2 and CH3NH3Br as precursors and butylamine (BTYA) and valeric acid (VA) as ligands, while MCs, with an absorption peak at 402 nm, are synthesized using solely PbBr2 and BTYA, without CH3NH3Br. Interestingly, PMSCs are converted spontaneously overtime into MCs. An isosbestic point in their electronic absorption spectra indicates a direct interplay between the PMSCs and MCs. Therefore, we suggest that the MCs are precursors to the PMSCs. From spectroscopic and extended X-ray absorption fine structure (EXAFS) results, we propose some tentative structural models for the MCs. The discovery of the MCs is critical to understanding the growth of PMSCs as well as larger perovskite quantum dots (PQDs) or nanocrystals (PNCs).

Eco friendly synthesis and characterization of zinc oxide nanoparticles from Aegle marmelos and its cytotoxicity effects on MCF-7 cell lines

An attempt was made to synthesize zinc oxide gum white nanoparticles (ZnO-GWNPs) by the greenway approach using Aegle marmelos (Bael fruit) juice extract as a capping and reducing agent. Synthesis of ZnO-GWNPs by greener approach is safer, more economical, more energy-efficient, eco-friendlier, and less toxic than chemically synthesized counterparts. The optical properties of the ZnO-GWNPs were ascertained through UV-Vis spectroscopy, Fourier Transform-Infrared (FT-IR), X-ray diffraction (XRD), High-resolution transmittance electron microscopy (HRTEM). A characteristic absorption peak at 385nm confirmed the presence of ZnO-GWNP using UV-Vis spectroscopy. FTIR spectrum revealed that the characteristic absorption peak of the Zn-O bond was observed at 467 cm-1. The XRD result for the ZnO showed the tendency of the three most intense diffraction peaks. The average crystallite size ZnO NPs at scattering angle (2θ) 22.89 and 32.15 was 39.14 and 26.08 nm and it showed the presence of miller indices of (100), (002), (101), (102) respectively. The EDX spectrum gave strong signals for zinc and oxygen indicating the occurrence of the nanoparticles in their oxide form rather than the pure zinc form. The SEM image showed the surface morphology of ZnO-GW NPs and the HR-TEM image showed the crystalline nature of ZnO-GW NPs. Cytotoxicity study of ZnO-GW NPs was determined against MCF-7 cell lines and the IC50 values were found to be 40 µg/mL and 60 µg/mL at 24 h and 48 h respectively.

A Novel Biological Approach to Copper Nanoparticles Synthesis: Characterization and its Application Against Phytopathogenic Fungi

Background: In nanotechnology, fungi are recognized as a good candidates for the creation of nanomolecules, so offering a cleaner alternative to synthesize novel resources with a varied array of potential requests in therapeutic and manufacturing fields. Materials and methods: In this respect, a novel biological approach Penicillium olsonii have demonstrated excellent synthesis capacity to produce copper nanoparticles (CuNPs). Characteristics of CuNPs were detected by variable tools including UV-Vis spectrum, Scanning Electron Microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) Results: UV-Vis spectra with characteristic absorption peak was observed at 565nm. Biomolecules mediating the synthesis and stabilizing the nano-fungicide was studied with FTIR that showed different functional groups. SEM investigations confirmed that size of CuNPs were varied from 6-26 nm. The antifungal activity of CuNPs was evaluated by testing against three phytopathogenic fungi including Fusarium oxysporum, Fusarium solani and Curvularia curvulatat with growth inhibition 86.25, 32.92 and 68.42 %, respectively at 200ppm. F. oxysporum was more affected by CuNPs followed by C. curvulata and F. solani.Conclusion: The current effort established that it's possible to achieve the production of CuNPs by P. olsonii with its fungicidal applicable potential.

Synthesis and Properties of Moisture-Cured Reactive Polyurethane Containing Castor Oil and Oxime Compounds

Reactive polyurethane hot-melt resin (moisture-cured reactive polyurethane, PUR) could successfully be prepared from poly(tetramethylene ether) glycol (PTMG), castor oil and dimethylglyoxime (DMG) by one or two-stage synthesis. Fourier-transform infrared spectroscopy (FTIR) analysis showed that the synthesis resins belonged to NCO-capped castor oil-based polyurethane. The thermal behaviors of the cured PUR were analyzed by differential scanning calorimeter (DSC) and dynamic mechanical analyzer (DMA) instruments. The results showed that the cured resin provided remeltable properties under the dosages of 3 wt% DMG. Furthermore, the phenomenon could be proved by FTIR analysis according to the characteristic absorption peak of NCO groups after the cured resin was heated. Comparing different syntheses, the resin prepared by one-stage synthesis showed random distribution of DMG with PUR structure and that prepared by two-stage synthesis had distribution of DMG with branching structure in the prepolymer. The former obtained lower remeltable temperatures from 90 to 130 °C than the latter temperatures, which had temperatures above 125 °C. The tensile test showed that all of the PUR films exhibited typical tough behavior. Thus, the cured resin with DMG dosages of 3 wt% provided remeltable and mechanical properties at the same time. Overall, the crosslinking density and numbers of dynamic bonds should be kept in balance for preparation of remeltable PUR.

Preparation and Application of Multi-functional His-AA-AuNCs Fluorescent Probe

Functional nanomaterials with simulated properties have become promising candidates for the detection of hydrogen peroxide. However, there are few studies on the colorimetric detection of metal ions and amino acids based on the peroxidase-simulation activity of amino acid functionalized AuNCs. In this study, a method for preparing fluorescent probe using histidine (His) and ascorbic acid (AA) as reductant and stabilizer was proposed. TMB was used as chromogenic substrate to indicate the catalytic process. The ultraviolet absorbance of oxTMB was determined at the characteristic absorption peak 625nm, and the standard curve was drawn to determine the concentration of H2O2 accurately. We found that Fe3+ can greatly improve the response signal of His-AA-AuNCs and has high selectivity. The linear range of H2O2 concentration detection is 10-9.97×106 μM. The concentration range of probe response to Fe3+ is 0.28-280 nM. The His-AA-AuNCs fluorescent probe was applied to intracellular fluorescence imaging after adriamycin injury, and the fluorescence intensity increased with the increase of probe concentration. This study was based on the double-stranded nature of amino acids and the properties of hydrogen peroxide mimic enzymes to detect other substances, which has a promising application prospect, and may potentially be applied to metal ions, amino acids and peptides in the biological and environmental fields in the future.