Morada 11 megapixel camera

The shape and size of the nanoparticles were inspected using the transmission electron microscope (TEM), JEM-1220 (JEOL, Tokyo, Japan) at 80 kV with a Morada 11-megapixel camera (Olympus Soft Imaging Solutions, Münster, Germany). An aliquot of 5 μL of 50 μg/mL ND sample was placed onto formvar-coated copper grids (Agar Scientific Ltd., Stansted, UK) and air dried prior to observation.

Transmission electron microscopy images (TEM) were performed to visualize the morphology of nanomaterials. Droplets of nanoparticles’ solutions at a concentration of 50 mg/L were placed onto Formvar-coated copper grids (Agar Scientific, Stansted, UK), and after air-drying, the grids were inspected by TEM (JEM-2000EX; JEOL, Tokyo, Japan) at 80 keV. The images were captured with a Morada 11-megapixel camera (Olympus Soft Imaging Solutions GmbH, Münster, Germany). In order to evaluate the stability of the nanoparticles’ hydrocolloids, zeta potential, and average hydrodynamic diameter measurements were performed. Measurements were conducted with a Zetasizer Nano-ZS90 analyzer (Malvern, Worcestershire, UK). Zeta potential was assessed for all nanostructures’ concentrations used in the experiments (3.13, 6.25, 50, 100 mg/L) after 120 s of stabilization at 25 °C using the micro-electrophoretic technique with the Smoluchowski approximation. The average hydrodynamic diameter of the nanostructures (using 6.25 mg/L concentration) was measured using a dynamic light scattering technique after 120 s of stabilization at 25 °C. Each measurement was repeated three times.

The shape of the GFM was inspected by a digital camera, scanning electron microscope (SEM), and transmission electron microscope (TEM). The macroscopic structure of GFM powder was visualized using the digital camera Nikon D7000 with the lens Nikon AF-S Micro-Nikkor 105 mm f/2.8G IF-ED VR (Nikon, Tokyo, Japan). SEM analysis of the GFM was performed by means of an FEI Quanta 200 electron microscope (FEI Co., Hillsboro, OR, USA). All imaging was performed in triplicate. Samples of GFM aqueous suspensions (25 μg/mL) for TEM observations were prepared by placing droplets of the suspension onto formvar-coated copper grids (Agar Scientific Ltd., Stansted, UK). Immediately after the droplets had air-dried, the grids were inserted into the TEM for observation with the JEM-2000EX TEM at 80 keV (JEOL, Tokyo, Japan), and images were captured with a Morada 11 megapixel camera (Olympus Soft Imaging Solutions GmbH, Münster, Germany).
Samples for TEM visualization of the interaction of the GFM with each bacterium were prepared by mixing suspensions (200 μL of 25 μg/mL) of pG, GO, and rGO with bacterial cell suspensions (200 μL containing ≈ 5 × 10⁸ cfu/mL in 0.85% NaCl). Control samples of bacteria were treated with ultrapure water. The samples were gently mixed for 15 min at room temperature, and then droplets of the samples were placed onto formvar-coated copper grids and observed by TEM.

NG were purchased from SkySpring Nanomaterials (Houston, USA), while nGO were prepared at the Institute of Electronic Materials Technology from NG through a modified Hummers’ method as previously described^{14 (link)}. The nanopowders were dispersed in ultrapure water to prepare 1 mg/ml solutions. Immediately prior to cell exposure, hydrocolloids of nanoparticles were sonicated for 30 min and diluted to different concentrations with supplemented Dulbecco’s modified Eagle’s medium (DMEM) (Thermo Fisher Scientific, Waltham, USA).
TEM images of nanoparticles were acquired using a JEM-1220 microscope (Jeol, Tokyo, Japan) at 80 kV with a Morada 11-megapixel camera (Olympus Soft Imaging Solutions, Münster, Germany). Samples were prepared by placing droplets of hydrocolloids onto formvar-coated copper grids (Agar Scientific, Stansted, UK) and air drying before observations.
Zeta potential measurements were carried out with the Nano-ZS90 Zetasizer (Malvern, Worcestershire, United Kingdom) at 25 °C using the Smoluchowski approximation. Each sample was measured after 120 s of stabilization at 25 °C (20 replicates). Nanoparticles were also examined by Raman spectroscopy using an inVia Raman Microscope (Renishaw, Gloucestershire, United Kingdom) with an Nd:YAG 532 nm laser. Hydrocolloids of nanoparticles were placed on a silicon substrate and incubated at 50 °C for 24 h to evaporate water.

The ultrastructure of the chosen nanomaterials was analysed using a JEM-1220 transmission electron microscope (JEOL, Tokyo, Japan) at 80 KeV with a Morada 11 megapixel camera (Olympus Soft Imaging Solutions, Münster, Germany).
A Zeta Sizer Nano-ZS90 analyser (Malven, Worcestershire, UK) was used to perform zeta potential measurements using a Smoluchowski approximation at 25 °C at a concentration of 20 mg/L for all of the nanomaterials, followed by an investigation of the hydrodynamic diameter of the nanomaterials that were suspended in ultrapure water at a concentration of 25 mg/L for metallic NPs, and 20 mg/L for the carbon-based nanomaterials. The measurements were performed by dynamic light scattering (DLS). Before analysis was performed, the water suspensions of NPs were first sonicated at 500 W and 20 kHz for 2 min and then centrifuged (5 min, 5000× g rpm).