Titan g2 chemistem

SEM images were taken from Zeiss scanning electron microscope. TEM was conducted on FEI Tecnai G² F20 TEM at an acceleration voltage of 200 kV. STEM–EDS characterization was carried out using a FEI Titan G² ChemiSTEM operated at an acceleration voltage of 200 kV. XRD was performed on PANalytical X-ray diffractometer. XPS spectra were collected on SSI S-Probe XPS Spectrometer. Inductive coupled plasma—atomic emission spectroscopy measurements were conducted on Varian Vista MPX; samples were first calcined in air at 600 °C for 30 min, then digested in concentrated HNO₃ and diluted to desired concentrations.

The crystal structure of the samples was investigated by X-ray diffraction (XRD) using Bruker D2 phaser (Bruker Corp., Billerica, MA, USA) with Cu-Kα radiation (λ = 1.54056 Å) in the range of 4° to 70° (2θ). Microstructures, such as the morphology and the interlayer distance of MRGO-HS, were determined using a field-emission scanning electron microscope (Hitachi SU8220, HITACHI, Tokyo, Japan) and a high-resolution transmission electron microscope (HRTEM) (Titan G2 ChemiSTEM, FEI Company, Hillsboro, OR, USA) with a 200-keV acceleration voltage. We also measured the Fourier transform infrared (FTIR) (Thermo Scientific Nicolet iS5, Thermo Fisher Scientific, Waltham, MA, USA) and Raman (Renishaw inVia reflex, Wotton-under-Edge, UK) spectra using KBr pellets to analyze the carbon bonds before and after the reduction of the synthesized samples. In addition, we used X-ray photoelectron spectroscopy (XPS) (Quantera SXM, ULVAC-PHI, Yokohama, Japan) to analyze the atomic composition of the surface. N₂ adsorption-desorption experiments were performed using Autosorb-iQ and Quadrasorb SI instruments (Quantachrome, Boynton Beach, FA, USA), and pre-experiment samples were dehydrated at 100 °C for 12 h using a vacuum oven. Thermogravimetric analysis (TGA) experiments in an ambient condition were conducted using an STA-S1000 analyzer (SCINCO, Co., Ltd, Seoul, Korea).

We prepared samples following previous protocol^{8 (link)}. Briefly, pellets of EVs were resuspended in 100 µL of 2% paraformaldehyde. Then, 5 µL of EVs and I-131-EVs were individually attached to the Formvar-carbon coated with EM grids (Electron Microscopy Sciences, USA) and dried and washed. The grids were then placed on 1% of glutaraldehyde and incubated at room temperature and then washed with distilled water. The EVs in the grids were stained with 2% uranyl acetate. Then, the grids were washed seven times with PBS, allowed to completely dry. The samples were observed on Titan G2 ChemiSTEM with a Cs Probe (FEI company, Netherlands) to measure the size of the EVs. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images were obtained.