Mira4

Cut medical tubing into 1 cm lengths and place them in a 6-well microtiter plate. Mix the tubing with bacterial cultures and different concentrations of EGCG (256, 128, and 64 μg/mL), and incubate for 24 hours. Subsequently, the tubing was washed multiple times with PBS, immersed in 2.5% glutaraldehyde for at least 24 hours, and then dried and dehydrated with 30%, 50%, 70%, 90% and 100% ethanol. The finished tubing was sprayed with gold and observed under scanning electron microscope (Tescan Mira4, China).

The morphology of the particles was examined through a Tescan Mira4 scanning electron microscope (Tescan, Shanghai, China). Samples were deposited onto double-sided tape and sputtered with gold for 200 s at 0.5 mbar atmosphere before the analysis. The imaging was achieved at 10 kV and 10 mA. The particle size of raw PTX, SAS processed PTX, and PTX coated onto the SAS-FB products was obtained by measuring more than 200 drug particles from different locations and various magnifications using a specialized image analysis software Image J [28 (link)].

The Fourier-transform infrared (FTIR) spectra of co-immobilized lipases were acquired in the range of 4000–400 cm⁻¹ using a Perkin Elmer Spectrum Two spectrometer. The size and surface morphology of co-immobilized lipases were recorded with a scanning electron microscope (MIRA4, TESCAN, Brno, Czech Republic). The magnetic properties of co-immobilized lipases were analyzed using a vibrating sample magnetometer (MicroSense EZ9, Lowell, MA, USA). A 5 mL volume of lipase solution (BCL or TLL, 2 mg/mL) was mixed with 100 μL of iso-Rhodamine B (RhB) or thiocyanate (FITC) solution (dimethyl sulfoxide, 1 mg/mL), respectively. After incubation in dark at 30 °C for 24 h, the unreacted FITC and RhB were removed by dialysis with distilled water for 48 h. Then, RhB-labeled BCL and FITC-labeled TLL were co-immobilized and observed using a confocal laser scanning microscope (CLSM, Olympus FV1200, Tokyo, Japan).

The hydrodynamic size of the samples was determined using a Nano ZS90 (Malvern, U.K.). The morphology of samples was recorded by using a microscope (Nikon, Japan), and also recorded using a scanning electron microscope (SEM) (TESCAN MIRA4, Oxford, U.K.). The SEM samples were dispersed in ethanol and attached to the SEM aluminum stubs, which were sputter-coated with a thin layer of gold before analysis.

The crystalline structures of the electrodes were investigated using the X-ray diffraction (XRD) equipment (Rigaku D-MAX 2500/PC, Tokyo, Japan) with a Cu Ka radiation source (λ = 0.15405 nm). The surface morphology of the electrode materials was analyzed using scanning electron microscopy (SEM, Tescan MIRA4, Jebulno, Czech Republic) and transmission electron microscopy (TEM, Tecnai G2F30, Hillsboro, OR, USA). The chemical composition and oxidation state were detected on X-ray photoelectron spectrometer (XPS, Thermo Scientific, ESCALAB 250XI, Waltham, MA, USA) with a Mg-Kα radiation source. The degradation experiment was carried out on an ultraviolet spectrophotometer (UV–vis, Beijing Puxi General Instrument Co., Ltd., Beijing, China).

A scanning electron microscope (SEM, MIRA4, TESCAN, Brno, Czech Republic) was used to observe the microscopic morphology of the micro-arc oxidation coatings. An X-ray diffractometer (XRD, Empyrean, Panaco, Almelo, The Netherlands) was used to analyze the phase structure. The thickness was measured using a coating thickness tester (ATS230, Test TIME, Beijing, China). The surface roughness was characterized using a confocal microscope (LSM900, ZEISS, Oberkochen, Germany). A microhardness tester (HVS-1000B, Zhongte, Dongguan, China) was used with a load of 500 g and 10 s. The tribological properties of the samples were tested using a UMT-2 tribological wear tester (UMT-2, CETR, San Jose, CA, USA) with a load of 2 N. The Tafel polarization curves of the Ti6Al4V alloy substrate and its micro-arc oxide film were tested using a CHI600E electrochemical workstation to obtain the corrosion current density, i_corr, and corrosion potential, E_corr, and to calculate the polarization resistance, R_p, of the film.

We made tooth sections from the mesial and distal surfaces of the teeth for scanning electron microscopy (SEM) and profilometry. The tooth surface roughness was measured using a profilometer (UP‐WLI; Rtec) before and after polishing in the three experimental groups. The copies used in SEM were 2 × 2 × 4 mm from the mesial and distal surfaces of each tooth, and we standardized the size and location of the scanned area in the middle of each copy. Before SEM, the sections were coated with gold through ion sputtering. The microstructures of the dental surfaces and the distributions of debris scratches were observed by SEM (Mira4; Tescan) in high vacuum (10,000×). To evaluate the ability of teeth to resist discoloration after polishing, we placed the teeth in 0.1% rhodamine B solution in a 37°C water bath condition for 24 h and rinsed them with distilled water for 10 s. Grand sections were cut from each tooth and an LSCM (A1; Nikon) was used to observe the staining bands and to measure the depth of the pigmentation bands (×10 objective for photography; excitation light wavelength 561 nm; emission wavelength 600 nm).
$$\text{Profilometer detection index}:\text{roughness ratio}=\frac{\text{RA value before polishing}}{\text{RA value after polishing}}.$$
Confocal measurements: band width.