scholarly journals Co0 superparamagnetic nanoparticles stabilized by an organic layer coating with antimicrobial activity

RSC Advances ◽  
2020 ◽  
Vol 10 (57) ◽  
pp. 34712-34718 ◽  
Author(s):  
Paula A. Santana ◽  
Carolina A. Castillo ◽  
Sebastián A. Michea ◽  
Diego Venegas-Yazigi ◽  
Verónica Paredes-García
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Solvothermal Synthesis ◽  
Superparamagnetic Nanoparticles ◽  
Organic Layer ◽  
Layer Coating ◽  
Scanning Electron

The Co0@C-NPs were obtained using solvothermal synthesis. The Co0@C-NPs were characterized by different techniques and its antimicrobial activity was assessed against Staphylococcus aureus by microdilution assay and scanning electron microscope.

scholarly journals SINTESIS KOMPOSIT KITOSAN/MgO/Ag DAN ANALISIS EFEKTIVITASNYA SEBAGAI ANTIBAKTERI

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Shintya Maryani ◽  
Henry F Aritonang ◽  
Vanda S Kamu
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Coprecipitation Method ◽  
Gram Positive ◽  
Gram Negative ◽  
X Ray ◽  
Ag Particles ◽  
Scanning Electron

Penelitian tentang sintesis komposit kitosan/MgO/Ag dengan variasi massa prekursor AgNO3 0,05 g, 0,1 g, 0,15 g dan 0,2 g disintesis dengan metode kopresipitasi. Komposit yang dihasilkan dikarakterisasi menggunakan X-Ray Diffractometry (XRD) dan Scanning Electron Microscope (SEM). Selanjutnya, keefektifan komposit ini sebagai antibakteri diuji yaitu Staphylococcus aureus (Gram positif) dan Escherichia coli (Gram negatif). Hasil penelitian menunjukkan bahwa puncak karakteristik partikel MgO dan Ag tidak muncul pada difraktogram XRD, tetapi secara visual dan morfologis SEM mendukung pembentukan dua partikel dan berdasarkan literatur dari hasil peneliti lain. Selain itu, komposit ini efektif dalam menghambat pertumbuhan kedua bakteri.       ABSTRACT Research on the synthesis of chitosan/MgO/Ag composites with variations in the mass of AgNO3 precursors 0.05 g, 0.1 g, 0.15 g and 0.2 g were synthesized by the coprecipitation method. The resulting composites were characterized using X-Ray Diffractometry (XRD) and Scanning Electron Microscope (SEM). Furthermore, the effectiveness of this composite as an antibacterial was tested, namely Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative). The results showed that the characteristic peaks of MgO and Ag particles did not appear on the XRD diffractogram, but visually and morphologically SEM supported the formation of two particles and based on the literature from the results of other researchers. In addition, this composite is effective in inhibiting the growth of both bacteria.

scholarly journals AKTIVITAS ANTI BAKTERI NANO PARTIKEL PERAK (NPP) HASIL BIOSINTESIS MENGGUNAKAN EKSTRAK KELADI SARAWAK Alocasia macrorrhizosTERHADAP Staphylococcus aureus DAN Escherichia coli

2022 ◽  
Vol 7 (1) ◽  
pp. 76-85
Author(s):  
Athiah Masykuroh ◽  
Heny Puspasari
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Surface Plasmon Resonance ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Surface Plasmon ◽  
Plasmon Resonance ◽  
Scanning Electron

Biosintesis Nano partikel perak (NPP) pada penelitian ini dilakukan dengan bantuan ekstrak air tanaman keladi sarawak Alocasia macrorrhizos sebagai bioreduktor dengan variasi konsentrasi larutan AgNO3 sebesar 0,05 M ; 0,10 M dan 0,15 M. Studi keberhasilan pembentukan NPP didasarkan pada pengamatan perubahan warna dan terbentuknya Surface Plasmon Resonance (SPR) dengan bantuan instrumen Spektofotometer UV-Visibel dan Scanning Electron Microscope (SEM). Uji Aktivitas antibakteri dilakukan dengan metode difusi kertas cakram. Hasil analisis menunjukkan bahwa NPP terbentuk maksimum pada panjang gelombang maksimum 450,00 nm yaitu pada variasi konsentrasi larutan AgNO3 0,15 M. Uji morfologi menggunakan SEM menunjukkan partikelnya berbentuk batang (nanorods) dengan ukuran diameter rata-rata masing-masing variasi 826,44 nm (0,05 M), 283,44 nm (0,10 M) dan 266,33 nm (0,15 M). NPP hasil biosintesis menunjukkan aktivitas antibakteri terhadap kedua jenis bakteri Staphylococcus aureus dan Escherichia coli pada pengenceran konsentrasi masing-masing variasi NPP sebesar 50%. Kata kunci :nanopartikel perak, keladi sarawak, staphylococcus aureus, escherichia coli

scholarly journals A Novel Ruthenium Based Coordination Compound Against Pathogenic Bacteria

2020 ◽  
Vol 21 (7) ◽  
pp. 2656
Author(s):  
Vishma Pratap Sur ◽  
Aninda Mazumdar ◽  
Pavel Kopel ◽  
Soumajit Mukherjee ◽  
Petr Vítek ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Coordination Compound ◽  
Mammalian Cells ◽  
Pathogenic Bacteria ◽  
Infection Model ◽  
Dead Cell ◽  
Microscopy Imaging ◽  
Scanning Electron

The current epidemic of antibiotic-resistant infections urges to develop alternatives to less-effective antibiotics. To assess anti-bacterial potential, a novel coordinate compound (RU-S4) was synthesized using ruthenium-Schiff base-benzimidazole ligand, where ruthenium chloride was used as the central atom. RU-S4 was characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and Raman spectroscopy. Antibacterial effect of RU-S4 was studied against Staphylococcus aureus (NCTC 8511), vancomycin-resistant Staphylococcus aureus (VRSA) (CCM 1767), methicillin-resistant Staphylococcus aureus (MRSA) (ST239: SCCmecIIIA), and hospital isolate Staphylococcus epidermidis. The antibacterial activity of RU-S4 was checked by growth curve analysis and the outcome was supported by optical microscopy imaging and fluorescence LIVE/DEAD cell imaging. In vivo (balb/c mice) infection model prepared with VRSA (CCM 1767) and treated with RU-S4. In our experimental conditions, all infected mice were cured. The interaction of coordination compound with bacterial cells were further confirmed by cryo-scanning electron microscope (Cryo-SEM). RU-S4 was completely non-toxic against mammalian cells and in mice and subsequently treated with synthesized RU-S4.

scholarly journals PEMBUATAN NANOKOMPOSIT KITOSAN/TiO2/Ag DAN ANALISIS AKTIVITASNYA SEBAGAI ANTIBAKTERI

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Gladys K Bungan ◽  
Henry F Aritonang ◽  
Audy D Wuntu
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Energy Dispersive ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chitosan Membrane ◽  
Ag Particles ◽  
Scanning Electron

Penelitian tentang pembuatan nanokomposit kitosan/TiO2/Ag telah dilakukan dengan menggunakan TiO2sebanyak6 gram dan konsentrasi AgNO3 yaitu 5 mM menggunakan metode reduksi dan impregnasi. Nanokomposit yang dihasilkan dikarakterisasi menggunakan X-Ray diffractometry (XRD), Scanning Electron Microscope-Energy Dispersive x-Ray Spectroscopy (SEM-EDS) dan menganalisis aktivitasnya sebagai anti bakteri terhadap Staphylococcus aureus (Gram positif) dan Escherichia coli (gram negatif). Hasil penelitian menunjukkan bahwa ukuran nanokomposit yang dihasilkan sebesar 56,93 nm. Difraktogram XRD muncul puncak karakteristik partikel TiO2 tetapi partikel Ag kurang terlihat jelas. Namun, berdasarkan data EDS, kedua partikel ini ditemukan pada membran kitosan. Ini menunjukkan bahwa sangat sedikit partikel Ag yang terbentuk atau keterbatasan alat XRD dalam mendeteksi sejumlah kecil partikel. Namun demikian, nanokomposit menunjukkan kemampuannya untuk menghambat pertumbuhan kedua bakteri ini.ABSTRACTResearch on the manufacture of chitosan/TiO2/Ag nanocomposites has been carried out using 6 grams of TiO2 and 5 mM AgNO3 using reduction and impregnation methods.The resulting nanocomposites were characterized using X-Ray diffraction (XRD), Scanning Electron Microscope-Energy Dispersive x-Ray Spectroscopy (SEM-EDS) and analyzed their activity as anti-bacteria against Staphylococcus aureus (Gram positive) and Escherichia coli (gram negative).The results showed that the resulting nanocomposite size was 56.93 nm. The XRD diffractogram showed the peak characteristics of TiO2 particles but the Ag particles were less visible.However, based on EDS data, the two particles were found on the chitosan membrane. This indicates that very few Ag particles are formed or the limitations of XRD devices in detecting a small number of Ag particles.However, the nanocomposites demonstrated their ability to inhibit the growth of these two bacteria.

The Alteration of the Pore Spaces in Sandstones

1973 ◽  
Vol 31 ◽  
pp. 210-211
Author(s):  
R. E. Ferrell ◽  
G. G. Paulson
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
The Other ◽  
Coarse Grained ◽  
Depositional Fabric ◽  
Soluble Components ◽  
Scanning Electron ◽  
Shape And Size

The pore spaces in sandstones are the result of the original depositional fabric and the degree of post-depositional alteration that the rock has experienced. The largest pore volumes are present in coarse-grained, well-sorted materials with high sphericity. The chief mechanisms which alter the shape and size of the pores are precipitation of cementing agents and the dissolution of soluble components. Each process may operate alone or in combination with the other, or there may be several generations of cementation and solution.The scanning electron microscope has ‘been used in this study to reveal the morphology of the pore spaces in a variety of moderate porosity, orthoquartzites.

The Broad Applications of the Scanning Electron Microscope

1969 ◽  
Vol 27 ◽  
pp. 20-21
Author(s):  
C. T. Nightingale ◽  
S. E. Summers ◽  
T. P. Turnbull
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Microscopy ◽  
Surface Topography ◽  
Great Depth ◽  
Resolving Power ◽  
Depth Of Field ◽  
Pictorial Representations ◽  
Scanning Electron

The ease of operation of the scanning electron microscope has insured its wide application in medicine and industry. The micrographs are pictorial representations of surface topography obtained directly from the specimen. The need to replicate is eliminated. The great depth of field and the high resolving power provide far more information than light microscopy.

Observability of Very Thick Specimen by Using Transmission Scanning Electron Microscope

1971 ◽  
Vol 29 ◽  
pp. 26-27
Author(s):  
K. Shibatomi ◽  
T. Yamanoto ◽  
H. Koike
Keyword(s):  
Electron Microscope ◽  
Image Quality ◽  
Scanning Electron Microscope ◽  
Chromatic Aberration ◽  
Image Contrast ◽  
Objective Lens ◽  
Thick Specimen ◽  
Transmission Electron ◽  
Scanning Electron

In the observation of a thick specimen by means of a transmission electron microscope, the intensity of electrons passing through the objective lens aperture is greatly reduced. So that the image is almost invisible. In addition to this fact, it have been reported that a chromatic aberration causes the deterioration of the image contrast rather than that of the resolution. The scanning electron microscope is, however, capable of electrically amplifying the signal of the decreasing intensity, and also free from a chromatic aberration so that the deterioration of the image contrast due to the aberration can be prevented. The electrical improvement of the image quality can be carried out by using the fascionating features of the SEM, that is, the amplification of a weak in-put signal forming the image and the descriminating action of the heigh level signal of the background. This paper reports some of the experimental results about the thickness dependence of the observability and quality of the image in the case of the transmission SEM.

Resolution of a Transmitted Electron Image Formed by A Scanning Electron Microscope

1970 ◽  
Vol 28 ◽  
pp. 386-387
Author(s):  
S. Takashima ◽  
H. Hashimoto ◽  
S. Kimoto
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Chromatic Aberration ◽  
Objective Lens ◽  
Specimen Thickness ◽  
Probe Diameter ◽  
Transmission Electron ◽  
Electron Image ◽  
Conventional Transmission Electron Microscope ◽  
Scanning Electron

The resolution of a conventional transmission electron microscope (TEM) deteriorates as the specimen thickness increases, because chromatic aberration of the objective lens is caused by the energy loss of electrons). In the case of a scanning electron microscope (SEM), chromatic aberration does not exist as the restrictive factor for the resolution of the transmitted electron image, for the SEM has no imageforming lens. It is not sure, however, that the equal resolution to the probe diameter can be obtained in the case of a thick specimen. To study the relation between the specimen thickness and the resolution of the trans-mitted electron image obtained by the SEM, the following experiment was carried out.

Sign in / Sign up

Export Citation Format

Share Document