Titan g2 60 300

Raman and PL spectroscopy were conducted using a Horiba LabRAM HR instrument with a laser wavelength of 532nm. Raman imaging was performed using a WiTec alpha300R system with a 532 nm light source (333 nm spot size) and a spectral resolution of +/−1 cm⁻¹. X-ray photoelectron spectroscopy (XPS) characterization was conducted using a Kratos AXIS ULTRA^DLD XPS system equipped with an A1 Kα monochromatic X-ray source and a 165 mm mean radius electron energy hemispherical analyzer along with a vacuum pressure of 3 × 10⁻⁹ Torr. FTIR measurements were taken using a Nicolet 6700 FTIR system having ATR accessory with a resolution of 0.500 cm⁻¹. Scanning transmission electron microscopy (STEM) imaging of the MoS₂ films were conducted using a FEI Titan G2 60–300 X-FEG aberration-corrected and STEM equipped system with a CEOS DCOR probe corrector. ADF-STEM images (2048 × 2048 pixel²) were acquired on the STEM operating at 200 keV using a dwell time of 3–6 µs per image pixel at a camera length of 130 mm. The beam convergence angle α_obj was measured to be 23 mrad. The ADF detector inner and outer angles of collection were measured to be 54 mrad and 317 mrad, respectively. Under these conditions, the measured probe size was ~0.8 Å.

The crystalline structures of the synthesized nanoparticles were detected using an X-ray diffractometer (XRD, DX-2700, China). The Raman spectra were determined using MultiRAM Raman spectroscopy (Bruker Corporation, Raman, Italy). The chemical states of the samples were determined using X-ray photoelectron spectroscopy (XPS, Escalab 250Xi, USA). The morphology, microstructure and particle size of the synthesized nanoparticles were measured using an SEM (HITACHI S4800, Tokyo, Japan) and a transmission electron microscope and high-resolution transmission electron microscopy (TEM and HRTEM, FEI Titan G2 60-300, USA) equipped with energy dispersive X-ray (EDX) spectroscopy. The optical absorption ranges of the samples were ascertained using UV-vis diffused reflectance spectroscopy (UV-vis DRS, Agilent cary 5000, USA).

Selected films were investigated using TEM. The instrument used for this characterization was a probe corrected FEI Titan G2 60–300 operated at 300 kV in scanning TEM mode (STEM). Cross section TEM samples were prepared by focused ion beam (FIB) milling on a JEOL JIB-4500 dual beam system. The surface morphology and coverage of the films were characterized using optical microscopy and scanning electron microscopy (SEM, Hitachi TM3000 & JEOL JIB-4500).

Scanning Transmission Electron Microscopy (STEM) was performed on an aberration corrected FEI Titan G2 60–300, operated at 300 kV. The microscope was equipped with a SuperX EDX spectrometer. The sample preparation of a MSP20 electrode (cycled at 2 mV s⁻¹/−0.2–0.6 V) and removed at 0.6 V was performed with ultramicrotomy after embedding in epoxy (Epofix, Struers, Germany). Ultrathin sections (<70 nm) were produced on the Leica Ultramicrotome UC6 (Leica Microsystems, Vienna, Austria) equipped with a 45° diamond knife (Diatome, Biel, Switzerland). After cutting, the thin sections were transferred to Quantifoil R3/3 TEM grids. Data acquisition and analysis were performed using the Gatan Digital Micrograph (GMS) Suite (v3.42, https://www.gatan.com/products/tem-analysis/gatan-microscopy-suite-software, accessed on: 3 April 2022). For determination of the iodine atomic positions the STEM HAADF, images were background corrected by subtracting a 128 times binned and subsequently rescaled copy of the corresponding.

AgNO₃ (99.99%), NaBH₄ (98%) and KNO₃ were purchased from Sigma-Aldrich. A novel DNA sequence of 5′-GGTTGGTGTGGTTGGATCCCCCCCCCCCC-3′ was synthesized by Shanghai Sangon Biotechnology Co. Ltd. (Shanghai, China). 5′-CCCCCCCCCCCC-3′(dC₁₂) was the scaffold for synthesis of AgNCs and 5′-GGTTGGTGTGGTTGG-3′ was the K⁺ ions aptamer which was widely used in a great deal of researches^{30 (link), 31 (link)}. A concentration of 20 mM phosphate-buffered (PB) was used throughout the experiments. Other reagents were of analytical grade and used without further purification. All stock solutions were prepared with double-distilled water filtered by Milli-Q (Millipore, Billerica, MA).
All fluorescence measurements were recorded on a fluorescence spectrophotometer (Hitachi, F-4600) using a 350 μL quartz cell. The emission spectra of DNA-AgNCs were recorded from 400 nm to 750 nm. Both the emission and the excitation slits were set to 10 nM, the scanning speed was 240 nm min⁻¹. The UV−vis absorption spectra were obtained on an UV−vis spectrophotometer (Shimadzu, UV-2450). The prepared DNA-AgNCs was analyzed by using a Titan G2 60–300 transmission electron microscope (TEM, FEI, USA). Estimation of the concentration of K⁺ levels was carried out using the automatic biochemistry analyzer instrument (Japan, HITACHI 7060).

The particle sizes and potential of PTFCG, PTFCG@M and PTFCG@MH were measured by a Malvern Zeta Sizer Nano series (Malvern, UK) at 25C. The morphologies and element content were investigated by TEM-EDS (Titan G2 60300, FEI, USA). For TEM-EDS analysis, the PTFCG or PTFCG@MH solution was dropped onto carbon film-coated copper grid and observed under TEM-EDS instrument. The UVvis absorption spectra were carried out on UVvisible spectrophotometer (Shimadzu, Japan). The fluorescence spectra were collected using FL-2700 spectrofluorometer (HITACHIH). The Ce6 concentration was determined by the UVvisible spectra spectrophotometer at 640nm. The loading amount of GOx was estimated using bicinchoninic acid (BCA) protein assay (Beyotime) and the protocol was provided by the supplier. The drug loading (DL) of Ce6 and GOx in the PTFCG@MH was calculated as follows:
$$\text{DL}=\text{amount of loaded drug in the PTFCG}@\text{MH}/\text{weight of PTFCG}@\text{MH}(\text{g}/\text{mg}).$$