http://users.encs.concordia.ca/~mojtaba/elec6271/silver%20nanoparticles.pdf

Silver nanoparticles: green synthesis and their antimicrobial activities.

Nanomaterials, such as metal or semiconductor nanoparticles and nanorods, exhibit similar dimensions to those of biomolecules, such as proteins (enzymes, antigens, antibodies) or DNA. The integration of nanoparticles, which exhibit unique electronic, photonic, and catalytic properties, with biomaterials, which display unique recognition, catalytic, and inhibition properties, yields novel hybrid nanobiomaterials of synergetic properties and functions. This review describes recent advances in the synthesis of biomolecule-nanoparticle/nanorod hybrid systems and the application of such assemblies in the generation of 2D and 3D ordered structures in solutions and on surfaces. Particular emphasis is directed to the use of biomolecule-nanoparticle (metallic or semiconductive) assemblies for bioanalytical applications and for the fabrication of bioelectronic devices.

Integrated Nanoparticle–Biomolecule Hybrid Systems: Synthesis, Properties, and Applications

/pdf/molecular-evolutionary-genetics-analysis-1uvpbl4lte.pdf

Molecular Evolutionary Genetics Analysis

Biological synthesis of metallic nanoparticles.

Nanotechnology involves the production, manipulation and use of materials ranging in size from less than a micron to that of individual atoms. Although nanomaterials may be synthesized using chemical approaches, it is now possible to include the use of biological materials. In this review, we critically assess the role of microorganisms and plants in the synthesis of nanoparticles.

Biosynthesis of nanoparticles: technological concepts and future applications

The development of reliable, eco-friendly processes for the synthesis of nanoscale materials is an important aspect of nanotechnology. In this paper, we report on the use of an alkalotolerant actinomycete (Rhodococcus sp.) in the intracellular synthesis of gold nanoparticles of the dimension 5–15 nm. Electron microscopy analysis of thin sections of the gold actinomycete cells indicated that gold particles with good monodispersity were formed on the cell wall as well as on the cytospasmic membrane. The particles are more concentrated on the cytoplasmic membrane than on the cell wall, possibly due to reduction of the metal ions by enzymes present in the cell wall and on the cytoplasmic membrane. The metal ions were not toxic to the cells and the cells continued to multiply after biosynthesis of the gold nanoparticles.

https://iopscience.iop.org/article/10.1088/0957-4484/14/7/323/pdf

Intracellular synthesis of gold nanoparticles by a novel alkalotolerant actinomycete, Rhodococcus species

Background: People globally are turning to herbal products to reconnect with nature. Cost efficacy and minimal side effects are the reasons for this changeover. This study assessed the effect of Amorphophallus paeoniifolius as an antimicrobial agent against Porphyromonas gingivalis, Prevotella intermedia, and Fusobacterium nucleatum. Aim: To determine and compare the antimicrobial activity of aqueous and ethanolic extracts of A. paeoniifolius on periodontal pathogens. Materials and Methods: Aqueous and ethanolic extracts of A. paeoniifolius were tested against the standard strains of the selected bacteria. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) were used. These tests assessed the lowest concentrations of test agent, either by showing a lack of turbidity or by no or few bacterial growth colonies, respectively. In this study, tetracycline hydrochloride was used as the control group. Results: Aqueous and ethanolic extracts of A. paeoniifolius showed antibacterial activity at various concentrations against the selected organisms. While assessing the MBC, the aqueous and ethanolic extracts of A. paeoniifolius and tetracycline hydrochloride exhibited bactericidal activity against F. nucleatum at all concentrations. The ethanolic extract of Amorphophallus paeoniifolius and tetracycline hydrochloride showed bactericidal action, whereas the aqueous extract exhibited bacteriostatic action against P. gingivalis. The aqueous and ethanolic extracts of A. paeoniifolius showed bacteriostatic action, whereas tetracycline hydrochloride showed bactericidal action against P. intermedia. Conclusion: Both aqueous and ethanolic extracts of A. paeoniifolius showed antibacterial activity against standard strains of P. gingivalis, P. intermedia, and F. nucleatum. The ethanolic extract showed a significant antibacterial effect against the selected microorganisms when compared to the aqueous extract of A. paeoniifolius.

Determination and comparison of antimicrobial activity of aqueous and ethanolic extracts of Amorphophallus paeoniifolius on periodontal pathogens: An in vitro study

V Srinivas

Papers

Intracellular synthesis of gold nanoparticles by a novel alkalotolerant actinomycete, Rhodococcus species

Determination and comparison of antimicrobial activity of aqueous and ethanolic extracts of Amorphophallus paeoniifolius on periodontal pathogens: An in vitro study