Nicolet is20

For FTIR analysis, powdered samples of GQD-EDA/1 g, GQD-EDA/5 g, and GQD-EDA/10 g, were mixed with KBr and compressed into pellets. Spectra were recorded using an FTIR spectrometer (Thermo Nicolet iS20, Waltham, Massachusetts, MA, USA) in the range of 4000–400 cm⁻¹ at 32 scans per spectrum at 4 cm⁻¹ resolution. For spectra analysis we used OMNIC 9 software version 9.9.509 by Thermo Fisher Scientific Inc. (Waltham, Massachusetts, MA, USA).

5 mg of GO was weighed and added to 1 L of ultrapure water, and sonicated for 30 min to afford evenly dispersed GO suspension. MCLR solution (60 µL), in a concentration of 1 mg/mL, was added to prepared GO suspension, GO-MCLR composite solution was obtained after well mixing. A drop of GO/GO-MCLR solution was placed on the copper net and slowly dried with nitrogen, then morphologies of GO/GO-MCLR were observed and photographed by by spherical aberration corrected Transmission Electron Microscope (ACTEM) (FEI TITAN 80-300 operating at 80 kV). The hydration particle sizes of all samples were obtained by Malvern laser particle size analyzer (ZetasizerNano-ZS90, Malvern Instruments, UK). The surface chemical states and functional groups of GO and GO-MCLR were investigated by FTIR (Nicolet IS20, Thermo Fisher Technology LTD, China) and XPS (Shimadzu, Japan). Microscopical laser Raman spectroscopy (MLRM) (Renishaw inVia Reflex, Wotton under Edge, UK) was used to obtain atomic vibration, phonon scattering and other information to study the molecular structure of GO and GO-MCLR.

The presence of various functional groups was assessed by Thermo Scientific Nicolet iS20 (Massachusetts, USA) spectrometer equipped with an attenuated total reflectance ATR accessory. The FT-IR spectra of the WF and AF fractions were achieved at a spectral resolution of 4 cm⁻¹ by 32 scans recorded between 650 and 4000 cm⁻¹, the graphs being evaluated with OMNIC software (9.9.549 version, Thermo Fisher Scientific, Waltham, MA, USA) based on previous studies, in order to identify the molecular characteristics of the flours^{28 (link)}.

Fourier transform infrared spectra (FT-IR) analysis was used to examine the chemical structure of these samples. The freeze-dried hydrogels were ground into powder and pressed into disks by mixing with potassium bromide (KBr) powder. The spectra were measured with an FT-IR spectrophotometer (Thermo Scientific Nicolet iS20, Waltham, MA, USA) over the spectral range of 4000–400 cm⁻¹.
To further prove the existence of the GO and β-TCP in the zwitterionic hydrogel, the characteristic phase and crystallinity were investigated via x-ray diffraction spectroscopy (Bruker D8 Advance) using 40 mA and 40 kV current. Data were recorded in the scanning range from 10° to 80° (2θ degrees) at a step size of 1°/min.

The morphology and surface properties of the titanium dioxide nanotubes were observed using a field emission scanning electron microscope (SEM, ZEISS Gemini 300, Germany) and transmission electron microscope (TEM, JEM-1200EX, Japan). The crystalline structure of the TNTs and HNK-TNTs were analyzed by X-ray diffraction (XRD) (Bruker D2 Phaser). Fourier Infrared Spectroscopy (FTIR) (Thermo Scientific Nicolet iS20) was used to compare the composition of TNTs and HNK-TNTs.