Jem 2100plus electron microscopy

The UV-vis-NIR absorption spectra and the film cyclic voltammograms (CV) were measured by a Shimadzu UV-3600 Plus spectrometer and CHI6600 electrochemical analyzer, respectively. Differential scanning calorimetry (DSC) curves were tested on a Q25 (TA instruments) differential scanning calorimeter. The whole tests were conducted under the nitrogen atmosphere with heating and cooling rates of 10°C/min. The melting point of various curves was identified as the endset point of the melting peak from the second heating curves. Nanoscale morphology of the samples was characterized by a MutiMode 8 atomic force microscopy (AFM, Bruker) in tapping mode. Transmission electron microscopy (TEM) images were conducted on a JEM-2100PLUS electron microscopy (JEOL) with an accelerating voltage of 200 kV. Grazing incidence wide-angle X-ray scattering (GIWAXS) experiments were carried out in Shanghai Synchrotron Radiation Facility (SSRF), at beamline BL14B1 with an incidence angle of ∼0.2° for complete penetration of X-ray into the films. The X-ray wavelength was 1.24 Å and the beam center along with the sample-to-detector distance were calibrated with LaB₆.

The hydrodynamic radius and ζ potential of the SNPs were measured using Malvern Panalytical Zetasizer Nano ZS (UK). Before and after the amino‐group functionalization process (amination), NH‐ group addition on the SiO₂ surface was characterized with Fourier transform infrared spectroscopy (Nicolet™ iS50 FTIR‐ OMNIC 0.9, ATR). The mesoporous shape of the SNPs was characterized by transmission electron microscopy (TEM) using a standard carbon grid with Jeol JEM‐2100 Plus Electron Microscopy (Japan). All SNPs were analyzed under agarose gel electrophoresis to characterize the binding affinity of CoV‐2 viral sequences and probes. Different combinations (such as SNPs, probe‐gated SNPs, and their viral complementary, and probes with viral complementary without SNPs) were loaded into the gel, and bands were analyzed using the BioRad ChemiDoc Imaging system (USA).