Jem 2100f microscope

SNP samples were characterized by UV/vis absorption (Shimadzu UV 1800; Shimadzu, Kyoto, Japan). The structural analysis was performed by X-ray diffraction (XRD; Shimadzu XRD 7000) and transmission electron microscopy (TEM) using a Jeol JEM-2100F microscope (Jeol, Tokyo, Japan; accelerating voltage 200 kV, point-to-point resolution 0.19 nm). The chemical analysis of the SNP solutions was carried out using an energy dispersive X-ray spectroscopy module (INCA, Oxford Instruments, Bristol, UK) attached to TEM (Jeol JEM-2100F). The size of the SNPs was characterized using TEM. Aliquots of the SNP solutions (5 and 10 μg/mL) were dropped onto a lacey carbon film supported by a copper grid and then air-dried before TEM observation. The particle sizes were characterized using conventional bright-field TEM images, and the structures were determined based on selected area electron diffraction patterns obtained from relatively large groups of particles. The mean size and standard deviation were calculated in random fields containing various numbers of particles. The morphology of the SNPs was analyzed by atomic force microscopy (SOLVER P47; ND-MDT, Moscow, Russia).

The powder X-ray
diffraction (XRD) characterization for phase identification was performed
on a Rigaku D/max-2550 X-ray diffractometer with high-intensity Cu
Kα (λ = 0.154 nm) radiation in the range of 5–90°.
The field emission scanning electron microscopy (FESEM) characterization
for morphological and microstructural evaluation was obtained on a
ZEISS Gemini300 microscope operating at 15 kV. The transmission electron
microscopy (TEM) and high-resolution TEM (HRTEM) characterizations
for interfacial and crystallographic analysis were examined on a JEOL
(JEM-2100F) microscope with an accelerating voltage of 200 kV. The
X-ray photoelectron spectroscopy (XPS) characterization for chemical
state recognition was conducted on an EscaLab Xi + photoelectron spectrometer.
UV–vis–NIR diffuse reflectance spectra for band gap
estimation were acquired on a PerkinElmer Lambda 950 UV–vis–NIR
spectrophotometer. Photoluminescence (PL) spectra for defect level
speculation were tested on a Hitachi F-7000 luminescence spectrometer
using a Xe lamp with an excitation wavelength of 325 nm. The specific
surface area of the sample was calculated through the Brunauer–Emmett–Teller
(BET) equation based on the nitrogen adsorption isotherm, which was
measured on a Micromeritics Gemini VII apparatus (surface area and
porosity system) with prior degassing of the product under vacuum
at 120 °C overnight.

Aggregated proteins from the microfluidic device were obtained by excising the PDMS block from the glass slides using a sterile scalpel and flushing the surfaces repeatedly with 100 μl of ultrafiltered deionized water. The collected liquid was refrigerated along with the remaining liquid in the reservoirs until further analysis. Procedures for collecting aggregated proteins from shaking experiments as well as for EM sample preparation were described previously^{7 (link)}. Negative stain EM data were collected on a JEOL JEM1400 electron microscope with a Gatan Orius 832 CCD. Cryo-EM data were collected on a JEOL JEM-2100F microscope with K2 Summit direct detector. Data were processed using EMAN2^{59 (link)} and RELION-4^{45 (link)} software packages.