Photocatalytic, antimicrobial activities of biogenic silver nanoparticles and electrochemical degradation of water soluble dyes at glassy carbon/silver modified past electrode using buffer solution

Selective and sensitive determination of one of the purine nucleotides, inosine (INO) using a low cost carbon dot (CD) modified glassy carbon (GC) electrode in 0.2 M phosphate buffer solution (pH 7.2) was demonstrated in this paper.

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Simultaneous electrochemical sensing of dihydroxy benzene isomers at cost-effective allura red polymeric film modified glassy carbon electrode

Journal of Analytical Science & Technology ◽

10.1186/s40543-021-00270-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Pattan-Siddappa Ganesh ◽

Ganesh Shimoga ◽

Seok-Han Lee ◽

Sang-Youn Kim ◽

Eno E. Ebenso

Keyword(s):

Glassy Carbon Electrode ◽

Glassy Carbon ◽

Limit Of Detection ◽

Tap Water ◽

Differential Pulse ◽

Oxidation Potential ◽

Electrochemical Sensing ◽

Carbon Electrode ◽

Buffer Solution ◽

Allura Red

Abstract Background A simple and simultaneous electrochemical sensing platform was fabricated by electropolymerization of allura red on glassy carbon electrode (GCE) for the interference-free detection of dihydroxy benzene isomers. Methods The modified working electrode was characterized by electrochemical and field emission scanning electron microscopy methods. The modified electrode showed excellent electrocatalytic activity for the electrooxidation of catechol (CC) and hydroquinone (HQ) at physiological pH of 7.4 by cyclic voltammetric (CV) and differential pulse voltammetric (DPV) techniques. Results The effective split in the overlapped oxidation signal of CC and HQ was achieved in a binary mixture with peak to peak separation of 0.102 V and 0.103 V by CV and DPV techniques. The electrode kinetics was found to be adsorption-controlled. The oxidation potential directly depends on the pH of the buffer solution, and it witnessed the transfer of equal number of protons and electrons in the redox phenomenon. Conclusions The limit of detection (LOD) for CC and HQ was calculated to be 0.126 μM and 0.132 μM in the linear range of 0 to 80.0 μM and 0 to 110.0 μM, respectively, by ultra-sensitive DPV technique. The practical applicability of the proposed sensor was evaluated for tap water sample analysis, and good recovery rates were observed. Graphical abstract Electrocatalytic interaction of ALR/GCE with dihydroxy benzene isomers.

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Biogenic silver nanoparticles as an antibacterial agent against bacterial leaf blight causing rice phytopathogen Xanthomonas oryzae pv. oryzae

Bioprocess and Biosystems Engineering ◽

10.1007/s00449-021-02579-7 ◽

2021 ◽

Author(s):

Karunakar Reddy Namburi ◽

Aruna Jyothi Kora ◽

Anuradha Chetukuri ◽

Vijaya Sree Meena Kumari Kota

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Agent ◽

Leaf Blight ◽

Xanthomonas Oryzae ◽

Bacterial Leaf Blight ◽

Biogenic Silver Nanoparticles

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Isolation and Optimization of Culture Conditions of Thraustochytrium kinnei for Biomass Production, Nanoparticle Synthesis, Antioxidant and Antimicrobial Activities

Journal of Marine Science and Engineering ◽

10.3390/jmse9060678 ◽

2021 ◽

Vol 9 (6) ◽

pp. 678

Author(s):

Kaliyamoorthy Kalidasan ◽

Nabikhan Asmathunisha ◽

Venugopal Gomathi ◽

Laurent Dufossé ◽

Kandasamy Kathiresan

Keyword(s):

Antimicrobial Activity ◽

Gold Nanoparticles ◽

Silver Nanoparticles ◽

Biomass Production ◽

Petroleum Ether Extract ◽

Antimicrobial Activities ◽

Culture Conditions ◽

Gold And Silver Nanoparticles ◽

Optimization Of Culture Conditions ◽

Antioxidant And Antimicrobial Activities

This work deals with the identification of a predominant thraustochytrid strain, the optimization of culture conditions, the synthesis of nanoparticles, and the evaluation of antioxidant and antimicrobial activities in biomass extracts and nanoparticles. Thraustochytrium kinnei was identified as a predominant strain from decomposing mangrove leaves, and its culture conditions were optimized for maximum biomass production of 13.53 g·L−1, with total lipids of 41.33% and DHA of 39.16% of total fatty acids. Furthermore, the strain was shown to synthesize gold and silver nanoparticles in the size ranges of 10–85 nm and 5–90 nm, respectively. Silver nanoparticles exhibited higher total antioxidant and DPPH activities than gold nanoparticles and methanol extract of the strain. The silver nanoparticles showed higher antimicrobial activity than gold nanoparticles and petroleum ether extract of the strain. Thus, Thraustochytrium kinnei is proven to be promising for synthesis of silver nanoparticles with high antioxidant and antimicrobial activity.

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The Antimicrobial and Anti-Inflammatory Effects of Silver Nanoparticles Synthesised from Cotyledon orbiculata Aqueous Extract

Nanomaterials ◽

10.3390/nano11051343 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1343

Author(s):

Caroline Tyavambiza ◽

Abdulrahman Mohammed Elbagory ◽

Abram Madimabe Madiehe ◽

Mervin Meyer ◽

Samantha Meyer

Keyword(s):

Staphylococcus Aureus ◽

Silver Nanoparticles ◽

Metallic Nanoparticles ◽

Methicillin Resistance ◽

Antimicrobial Activities ◽

Transmission Electron ◽

Anti Inflammatory ◽

Anti Inflammation ◽

Important Medicinal Plant ◽

Pro Inflammatory Cytokines

Cotyledon orbiculata, commonly known as pig’s ear, is an important medicinal plant of South Africa. It is used in traditional medicine to treat many ailments, including skin eruptions, abscesses, inflammation, boils and acne. Many plants have been used to synthesize metallic nanoparticles, particularly silver nanoparticles (AgNPs). However, the synthesis of AgNPs from C. orbiculata has never been reported before. The aim of this study was to synthesize AgNPs using C. orbiculata and evaluate their antimicrobial and immunomodulatory properties. AgNPs were synthesized and characterized using Ultraviolet-Visible Spectroscopy (UV-Vis), Dynamic Light Scattering (DLS) and High-Resolution Transmission Electron Microscopy (HR-TEM). The antimicrobial activities of the nanoparticles against skin pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Methicillin Resistance Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans) as well as their effects on cytokine production in macrophages (differentiated from THP-1 cells) were evaluated. The AgNPs from C. orbiculata exhibited antimicrobial activity, with the highest activity observed against P. aeruginosa (5 µg/mL). The AgNPs also showed anti-inflammatory activity by inhibiting the secretion of pro-inflammatory cytokines (TNF-alpha, IL-6 and IL-1 beta) in lipopolysaccharide-treated macrophages. This concludes that the AgNPs produced from C. orbiculata possess antimicrobial and anti-inflammation properties.

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