Em 900 microscope

Exosomes were fixed in 2% paraformaldehyde and adsorbed onto formvar/carbon-coated 200-mesh nickel grids (Electron Microscopy Sciences) for 15 min. The grids were then washed with PBS, fixed in 2.5% glutaraldehyde for 5 min, and rinsed with milliQ water. Finally, the grids were negatively stained with 2% uranyl acetate for 1 min and then washed and air-dried overnight. Images were acquired on a Zeiss EM900 microscope (Carl Zeiss Microscopy GmbH) equipped with a wide-angle, dual-speed 2K-CCD camera at 80 kV.

The structural characterisation of BPNFs after exfoliation was carried out using Raman spectroscopy. Raman spectra of dry samples were acquired using a Renishaw inVia microscope equipped with a 514 nm laser. A 100× objective lens was employed, and the laser power and the exposure time were 1% and 3 s, respectively, in all the experiments. Different areas of the sample were tested, and at least 10 different spectra were obtained to represent the average spectra shown in this paper. UV–Vis absorption spectra were recorded on a Cary 100 (Varian) spectrophotometer at room temperature using a slit width of 0.4 nm and a scan rate of 600 nm/min. Transmission electron microscopy was performed with a Zeiss EM 900 microscope (Carl Zeiss Microscopy GmbH, Jena, Germany) at 80 kV.

Foot process effacement was assessed by measuring the width in TEM images (7000x magnification) captured with a Zeiss EM-900 microscope. Images of all viable glomerular loops from two glomeruli were evaluated using ImageJ 1.53 software. The glomerular loop length (μm) was divided by the number of foot processes observed in the respective loop. The mean values of each DN sample mean underwent factor π/4 correction to normalize the presumed random variation of the section angle related to the long axis of the podocyte [16 (link)]. The mean foot process width (FPW) of each biopsy evaluated was expressed in nanometers (nm) [12 (link)].

Fourier transform infrared (FT-IR) spectra was registered on an ALPHA-Bruker spectrometer from 400 to 4000 cm⁻¹, using KBr pellet. ¹H-NMR (300 MHz) and ¹³C-NMR (75 MHz) were carried out in CDCl₃ on a Bruker-Avance spectrometer. The thermogravimetry analysis (TGA) was performed on a Q600 TA instrument under an argon atmosphere at 25–800 °C. X-ray diffraction (XRD) data were examined by X’Pert- MPD PRO-PW3040/60 instrument. The surface morphology and atomic distribution were obtained by field emission scanning electron microscope (FE-SEM) brand TESCAN (MIRA 3 LMU). Zeiss EM900 microscope was used for Transmission electron microscopy (TEM) analysis. The surface area, pore volume, and pore size distribution were characterized on a BELSORP MINI II system at 77 K using N₂ as the adsorbate. The UV–Visible (UV–Vis) spectra of the methyl red dye solutions were recorded using a UV-2550 spectrophotometer.