scholarly journals Myco-Fabricated Gold Nanoparticles from Aspergillus Tamarii MTCC5152, its Characterization and Dye Biodegradation

2021 ◽  
pp. 52-62
Author(s):  
Ragavy Radhakrishnan ◽  
Uthirappan Mani ◽  
Arumugam Gnanamani ◽  
Muthiah Shanmugavel
Keyword(s):  
Gold Nanoparticles ◽  
Zeta Potential ◽  
Ftir Spectroscopy ◽  
Dye Degradation ◽  
Visual Observation ◽  
Surface Plasmon Resonance Peak ◽  
Sem Images ◽  
Aspergillus Tamarii ◽  
Plasmon Resonance Peak ◽  
Average Size

This work was initiated to investigate the myco-fabrication of gold nanoparticles (AuNPs) using a fungal strain, Aspergillus tamarii 5152 (A. tamarii MTCC 5152). The biosynthesized gold nanoparticles were characterized by visual observation, and using UV-Vis and FTIR spectroscopy, DSC, TGA, Zeta-potential, DLS and SEM analyses. NADH-dependent cofactor analysis and photocatalysis assays were carried out for NADH-dependent AuNPs biosynthesis and dye degradation ability. A maximum surface plasmon resonance peak for the AuNPs was recorded at 535 nm, followed by the identification of protein capping effect of the extract by FTIR spectroscopy. The average size (Z) of the nanoparticles observed was 39.15 nm, while SEM images showed crystallized rod-shaped structures ranging from 55-91 nm. A negative zeta potential of 10.5 mV showed repulsion between the nanoparticles, which indicates the stabilizing power of the fungal extract. Further, it was observed that NADH acts as a cofactor for the nanoparticle biosynthesis. The AuNPs were found to degrade crystal violet dye by 63%. From this study, it can be understood that the process of fungal mediated biosynthesis of AuNPs by A. tamarii MTCC 5152 is simple, less expensive, and could be utilized for bioremediation of toxic dye accumulation.

scholarly journals Comparative Study on Inhibition of Pancreatic Cancer Cells by Resveratrol Gold Nanoparticles and a Resveratrol Nanoemulsion Prepared from Grape Skin

Pharmaceutics ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1871
Author(s):  
Baskaran Stephen Inbaraj ◽  
Leng-Huei Hua ◽  
Bing-Huei Chen
Keyword(s):  
Pancreatic Cancer ◽  
Particle Size ◽  
Gold Nanoparticles ◽  
Zeta Potential ◽  
Cancer Cells ◽  
Surface Plasmon Resonance Peak ◽  
Grape Skin ◽  
Plasmon Resonance Peak ◽  
Mean Particle Size ◽  
Pancreatic Cancer Cells

Resveratrol, a phenolic compound possessing vital biological activities such as anti-cancer, is present abundantly in grape skin, a waste produced during the processing of grape juice. The objectives of this study were to prepare resveratrol-gold nanoparticles and a resveratrol nanoemulsion from grape skin and study their inhibition effects on pancreatic cancer cells BxPC-3. The spherical-shaped citrate gold nanoparticles (GNPs) and resveratrol-gold nanoparticles (R-GNPs) were, respectively, prepared with a surface plasmon resonance peak at 528 and 538 nm, mean particle size of 20.8 and 11.9 nm, and zeta-potential at −32.7 and −66.7 mV, by controlling an appropriate concentration of citrate/resveratrol and gold chloride as well as stirring time and temperature. The resveratrol nanoemulsion, composed of soybean oil, Tween 80, and sucrose fatty acid ester in glycerol and water, possessed a high storage stability with a mean particle size of 14.1 nm, zeta-potential of −49.7 mV, and encapsulation efficiency of 95.5%. An antiproliferation study revealed that both R-GNPs and resveratrol nanoemulsion could effectively inhibit the growth of pancreatic cancer cells BxPC-3, with the latter showing a higher inhibition effect. Western blot analysis implied that both can down-regulate expressions of cyclin A, cyclin B, CDK1, and CDK2 and up-regulate expressions of p53 and p21, accompanied by enhancing cytochrome C expression, decreasing BcL-2 expression, increasing Bax expression, and leading to the elevation of caspase-8, caspase-9, and caspase-3 activities for cell apoptosis execution. Future research is needed to study the inhibition of pancreatic tumors in vivo by R-GNPs and resveratrol nanoemulsions.

Spectral studies of silver nanoparticles biosynthesized by Origanum majorana

2018 ◽  
Vol 7 (2) ◽  
pp. 100-105 ◽  
Author(s):  
Moustafa Zahran ◽  
Maged El-Kemary ◽  
Shaden Khalifa ◽  
Hesham El-Seedi
Keyword(s):  
Silver Nanoparticles ◽  
Zeta Potential ◽  
Metallic Nanoparticles ◽  
Spectral Studies ◽  
Surface Plasmon Resonance Peak ◽  
Plasmon Resonance Peak ◽  
Biosynthesized Agnps ◽  
The Stability ◽  
Origanum Majorana ◽  
Average Size

AbstractSilver nanoparticles (AgNPs) were biologically synthesized in an eco-friendly manner using aqueous leaf extract ofOriganum majoranaplant and silver nitrate (AgNO3) solution. Size, shape, and crystallinity of the biosynthesized AgNPs were determined by using a transmission electron microscope (TEM). Zeta potential analyzer was used to prove the stability of the metallic nanoparticles, while Fourier transform infrared spectroscopy was used to identify the bioreducing and capping agents. AgNPs were electrochemically investigated using cyclic voltammetry (CV), while the optical properties of the metallic nanoparticles were studied using UV-Vis and fluorescence spectroscopies. According to TEM images, AgNPs are spherical with an average size of 35 nm. TEM also refers to the presence of mono and polycrystalline AgNPs. The value of zeta potential (−39 mV) proved the stability of AgNPs caused by capping molecules ofO. majoranaplant. CV studies showed that AgNPs were electrochemically investigated at 0.39 mV. AgNPs showed a surface plasmon resonance peak at 440 nm, while the emission peak was detected at 466 nm. These nanoparticles are promising for many industrial and medical applications.

scholarly journals In vitro and in vivo applications of Euphorbia wallichii shoot extract-mediated gold nanospheres

2021 ◽  
Vol 10 (1) ◽  
pp. 101-111
Author(s):  
Rehman Ullah ◽  
Sumaira Shah ◽  
Zahir Muhammad ◽  
Sajjad Ali Shah ◽  
Shah Faisal ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Muscular Contraction ◽  
Surface Plasmon Resonance Peak ◽  
Plasmon Resonance Peak ◽  
Optical Absorption Peak ◽  
Visible Spectra ◽  
Scattering Spectra ◽  
Dose Dependent

Abstract The current study was designed to investigate the potential of Euphorbia wallichii shoot extract for reducting Au3+ and stabilizing gold nanoparticles. UV-visible spectra of gold nanoparticles showed obvious surface plasmon resonance peak at 548 nm. Microscopy (SEM and TEM) showed spherical dimensions, and the energy dispersive X-ray spectra displayed the strongest optical absorption peak for gold (Au) at 2.1 keV. Dynamic light scattering spectra represent polydispersed mixture with particulate diameter of 2.5–103.2 nm. The IR spectra confirm the potential functional groups of shoot extract responsible for the reduction of Au3+ to gold nanoparticles which exhibit tremendous antibacterial potential of 76.31%, 68.47%, 79.85%, 48.10%, and 65.53% against Escherichia coli, Staphylococcus aureus, Bacillus pumilus, Pseudomonas aeruginosa, and Klebsiella pneumoniae, respectively. Gold nanoparticles showed markedly elevated fungicidal potency compared to the shoot extract alone against the tested fungal strains. IC50 for 2,2-diphenyl-1-picrylhydrazyl scavenging was 31.52, 18.29, and 15.32 µg/mL at 30, 60, and 90 min of reaction time, respectively. Both shoot extract and nanoparticles revealed 71% mortality at 100 µg/mL, with LD90 values of 310.56 µg/mL. Experimental mice acquired dose-dependent analgesia of 54.21%, 82.60%, and 86.53% when treated with gold nanoparticles at 50, 100, and 200 mg/kg bw. Inhibition of gastrointestinal muscular contraction was 21.16%, 30.49%, and 40.19% in mice feed with 50, 100, and 200 mg/kg bw, respectively.

scholarly journals Green Synthesis and Catalytic Activity of Silver Nanoparticles Based on Piper chaba Stem Extracts

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1777 ◽  
Author(s):  
Md. Mahiuddin ◽  
Prianka Saha ◽  
Bungo Ochiai
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Ftir Spectroscopy ◽  
Visual Observation ◽  
Face Centered Cubic ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Face Centered ◽  
Average Size

A green synthesis of silver nanoparticles (AgNPs) was conducted using the stem extract of Piper chaba, which is a plant abundantly growing in South and Southeast Asia. The synthesis was carried out at different reaction conditions, i.e., reaction temperature, concentrations of the extract and silver nitrate, reaction time, and pH. The synthesized AgNPs were characterized by visual observation, ultraviolet–visible (UV-vis) spectroscopy, dynamic light scattering (DLS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), energy dispersive x-ray (EDX), and Fourier transform infrared (FTIR) spectroscopy. The characterization results revealed that AgNPs were uniformly dispersed and exhibited a moderate size distribution. They were mostly spherical crystals with face-centered cubic structures and an average size of 19 nm. The FTIR spectroscopy and DLS analysis indicated that the phytochemicals capping the surface of AgNPs stabilize the dispersion through anionic repulsion. The synthesized AgNPs effectively catalyzed the reduction of 4-nitrophenol (4-NP) and degradation of methylene blue (MB) in the presence of sodium borohydride.

Facile and Novel Synthesis of Spiky Gold Nanoparticles as an Efficient Antimicrobial Agent against Pseudomonas Aeruginosa

2021 ◽  
Vol 24 ◽  
Author(s):  
Farooq Aziz ◽  
Muhammad Rashid ◽  
Mubashar Rehman ◽  
Muhammad Rafique ◽  
Muhammad Imran
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Gold Nanoparticles ◽  
Biomedical Applications ◽  
Antibacterial Agents ◽  
Reduction Method ◽  
Surface Plasmon Resonance Peak ◽  
Gram Negative Bacteria ◽  
Plasmon Resonance Peak ◽  
Gram Negative ◽  
Novel Synthesis

Aims: The study aims to develop advanced antibacterial agents as nanoparticles instead of antibiotics due to the emergence of antimicrobial resistance. Background: Pseudomonas aeruginosa is capable of causing many diseases, including severe bacterial pneumonia. There is a need for an efficient antibacterial agent to kill these pathogens. Objective: The objective of the study is to synthesize advanced antibacterial agents as nanoparticles for biomedical applications that can play a vital role in killing Gram-negative bacteria (Pseudomonas aeruginosa). Method: A novel fabricated growth of hydrophilic spiky gold nanoparticles (SGNPs) via reduction method is reported. Results: The surface plasmon resonance peak of the synthesized SGNPs was tuned under the near-infrared range. The SGNPs have anisotropic and spiky morphology with 68 nm size and -58 mV surface charge. They are pure, possessing adsorption similar to the organic material. Pseudomonas aeruginosa treated with synthesized SGNPs showed 60% bacterial death at the concentration of 100 μM. Conclusion: This work consists of the novel synthesis of SGNPs via a safe and simple reduction method. The synthesized SGNPs exhibit strong antibacterial activity against the Gram-negative bacteria Pseudomonas aeruginosa measured using a microplate assay test. The result showed that these SGNPs are ideal for biomedical applications.

Role of Collagen Concentration in Stability of Star-Shaped Silver@Gold Nanoparticles

2016 ◽  
Vol 40 ◽  
pp. 113-119 ◽  
Author(s):  
Phuong Phong Nguyen Thi ◽  
Minh Tien Nguyen ◽  
Dai Hai Nguyen
Keyword(s):  
Gold Nanoparticles ◽  
Ph Value ◽  
Critical Role ◽  
Component Ratio ◽  
Surface Plasmon Resonance Peak ◽  
Collagen Concentration ◽  
Plasmon Resonance Peak ◽  
Nanoparticles Stability ◽  
The Stability ◽  
Growth Approach

In this report, star-shaped silver@gold (Ag@Au) nanoparticles were synthesized in collagen (Coll) suspensions by a seeding growth approach. The silver nanoparticles were used as seeds for Au development. Coll was used as a protecting agent and the effect of its concentration on stability was also examined. Obtained nanoparticles were then characterized by UV-Vis, TEM, XRD and FTIR. The result was confirmed by the maximum surface plasmon resonance peak at 566-580 nm for each sample indicating the formation of branched Ag@Au@Coll NPs. The average diameters of the branched Ag@Au@Coll NPs were revealed to be 30-50 nm depending on the corresponding component ratio and the pH value. It is interesting to note that the concentration of Coll plays a critical role in the stability of the star-shaped gold nanoparticles. The results offer an understanding of the handling of the electronic and the silver@gold based nanoparticles stability properties.

scholarly journals Plant Extract (Bupleurum falcatum) as a Green Factory for Biofabrication of Gold Nanoparticles

2015 ◽  
Vol 10 (9) ◽  
pp. 1934578X1501000
Author(s):  
You Jeong Lee ◽  
Song-Hyun Cha ◽  
Kyoung Jin Lee ◽  
Yeong Shik Kim ◽  
Seonho Cho ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Plant Extract ◽  
Average Diameter ◽  
Reduction Reaction ◽  
Surface Plasmon Resonance Peak ◽  
Face Centered Cubic ◽  
Plasmon Resonance Peak ◽  
Nitrophenol Reduction ◽  
Diffraction Patterns ◽  
Bupleurum Falcatum

This work describes a biofabrication process for gold nanoparticles in which the plant extract ( Bupleurum falcatum) is used as a reducing agent to convert gold ions to gold nanoparticles. Biofabricated gold nanoparticles with spherical shapes were observed with an average diameter of 10.5 ± 2.3 nm. The color of the gold nanoparticles was purple, with a surface plasmon resonance peak at 542 nm. The face-centered cubic structure of crystalline gold was confirmed by high-resolution X-ray diffraction patterns. The biofabricated gold nanoparticles demonstrated excellent catalytic activity towards the 4-nitrophenol reduction reaction. The current report suggests that plant extracts are valuable natural sources for the biofabrication of gold nanoparticles with excellent catalytic activities.

Green synthetic approach for starch capped silver nanoparticles and their antibacterial activity

2016 ◽  
Vol 88 (1-2) ◽  
pp. 61-69 ◽  
Author(s):  
Precious Nokwethemba Sibiya ◽  
Thokozani Xaba ◽  
Makwena Justice Moloto
Keyword(s):  
Silver Nanoparticles ◽  
Synthesis Method ◽  
Spherical Shape ◽  
Cubic Phase ◽  
Hydroxyl Groups ◽  
Synthetic Approach ◽  
Surface Plasmon Resonance Peak ◽  
Plasmon Resonance Peak ◽  
Transmission Electron ◽  
Average Size

AbstractIn this work silver nanoparticles (AgNPs) have been prepared from silver nitrate (AgNO3) precursor using a green synthesis method at room temperature. Starch with its abundance of hydroxyl groups and its biocompatibility was used as a capping and reducing agent. The formation of AgNPs was confirmed by absorption spectroscopy with the surface plasmon resonance peak at 400 nm. The sharp reflection at (111), (200), (220) and (311) was observed by powder X-ray diffraction (XRD), which indicated the presence of cubic phase AgNPs. Transmission electron microscopy (TEM) revealed that the average size of AgNPs were between 0.5 and 4 nm with a spherical shape under optimum conditions. The nanoparticles showed a decrease in size with an increase in precursor concentration as well as the increase in capping agent concentration. The nanoparticles also showed to be bactericidal towards the tested Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria.

scholarly journals Characterization of Biocompatible Gold Nanoparticles Synthesized by using Curcuma xanthorrhiza and their Catalytic Activity

2020 ◽  
Vol 16 (2) ◽  
pp. 214-225
Author(s):  
Khairiza Lubis ◽  
Nuannoi Chudapongse ◽  
Hau Van Doan ◽  
Oratai Weeranantanapan
Keyword(s):  
Electron Microscopy ◽  
Gold Nanoparticles ◽  
Catalytic Activity ◽  
Ftir Spectroscopy ◽  
Dye Degradation ◽  
Chemical Properties ◽  
Reduction Process ◽  
Industrial Applications ◽  
Biological Synthesis ◽  
Curcuma Xanthorrhiza

Background: Based on various distinguished physical and chemical properties of gold nanoparticles, they have far wide applications in several areas of industry and medicine, such as catalysis, bio-sensor and drug delivery. Compared to a chemical method, biological synthesis is an economical and less toxic process, thus it is a better alternative for nanoparticle synthesis. In this study, an environmentally friendly method was chosen to produce AuNPs using Curcuma xanthorrhiza. Methods: Alkaline aqueous extract of C. xanthorrhiza rhizomes, which acts as a reducing and stabilizing agent was used to produce AuNPs by bio-reduction of HAuCl4. The formation of AuNPs was periodically monitored by UV-visible spectroscopy. The obtained AuNPs were characterized by Xray diffraction, energy dispersive spectroscopy, scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared (FTIR) spectroscopy. Catalytic activity and toxicity of the AuNPs were evaluated. Results: The AuNPs obtained from this study mostly were spherical in shape with approximately 15 nm in size. The presence of functional groups derived from C. xanthorrhiza rhizome extract involved in the gold bio-reduction process was confirmed by the spectrum of FTIR spectroscopy. The biosynthesized AuNPs at the concentration of 0.5 μg/ml had catalytic activity in dye degradation of Congo red. The results showed that this biogenic AuNPs did not cause any toxicity to zebrafish embryos and all tested cell lines. Conclusion: The biocompatible AuNPs with catalytic activity were successfully fabricated with C. xanthorrhiza rhizome extract by simple eco-friendly and inexpensive method. This catalytic activity of the obtained AuNPs is potentially useful for industrial applications as well as nanoscience and nanotechnology.

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