Ftir 460 spectrometer

The JASCO FT-IR-460 spectrometer has been utilized for Fourier transformed infrared spectroscopy (FT-IR) in the field of 400–4000 cm⁻¹. An automated Philips X'Pert X-ray diffractometer obtained powder X-ray diffraction (PXRD) spectra with Cu K radiation (40 kV and 30 mA) for 2θ values over the range of 10–80. The synthesized (nano)particle morphology and elemental analysis (FESEM, EDS, and map) have been observed under an acceleration voltage of 30–250 by a field emission scanning electron microscope (TESCAN MIRA-3). To record the (UV–Vis) spectra at the range of 200–800 nm, the Perkin Elmer Lambda 25 has been utilized. The nanoparticle size was screened by (DLS) analysis and (Horiba SZ100). The fluorescence spectrometer (PerkinElmer, USA) was utilized for recording (PL analysis).

The samples for FT-IR spectroscopy were analyzed in the solid state as potassium bromide (KBr) pellets. The lyophilized samples were mixed with KBr to a final concentration of approximately 1 wt%. FT-IR spectra were recorded on a Jasco FTIR-460 spectrometer. Each spectrum is the result of signal-averaging of 256 scans at a resolution of 2 cm⁻¹. All spectra are presented as absorbance spectra after background subtraction.

About 1–2% of lyophilized hydrogel was mixed with potassium bromide (KBr), ground to a fine powder and pressed to form a pellet. IR spectra were recorded on a Jasco FTIR‐460 spectrometer. Each spectrum is the result of signal‐averaging of 256 scans at a resolution of 2 cm⁻¹. All spectra are absorbance spectra obtained after background subtraction. Smoothing of spectra was carried out with a step of 11 or 13 data points, using the Savitzky–Golay function. Second derivatives of the spectra were obtained using a step of 13 datapoints to identify discrete absorption bands that make up the complex amide profiles. Quantitative analysis of the individual component bands of amide I was achieved by using the peak fitting module implemented in the Origins® Software (Microcalc Inc.).

FTIR was performed with the JASCO FTIR 460 spectrometer (Easton, MD USA). A transmission mode with 16 scans and a resolution of 2 cm⁻¹ in the spectral range from 400 to 4000 cm⁻¹ was applied to the analyses. In addition, we employed NMR spectroscopy to analyze the chemical structure of RE and RBE. Both ¹H NMR and ¹³C NMR analyses were performed using the Bruker AVANCE 600 MHz NMR spectrometer, Bruker (Billerica, MA USA) with deuterated dimethyl sulfoxide (DMSO-d₆) as the solvent at 30 °C. RE and RBE were analyzed using a TA Q5000, TA Instruments (New Castle, DE, USA) thermogravimetric analyzer (TGA). Their thermograms were recorded at a heating rate of 10 °C/min from 50 °C to 750 °C in a nitrogen flow (20 mL/min). The compositions of RE and RBE were determined by high-performance liquid chromatography-mass spectrometry mass spectrometry (LC/MS/MS) using an Agilent 110 HPLC unit (Agilent Technologies, Palo Alto, CA, USA). A C18 column (4.6 mm × 250 mm × 5 μm with a guard column, Sigma-Aldrich, Oakville, ON, Canada) was used for separation. The mobile phase was methanol/5% acetonitrile in water at different ratios (60:40–95:5 v/v) varying from 0 to 70 min at 0.8 mL/min, and the compounds were detected at 306 nm.

Bruker diffractometers (PW1730) were used to carry out X-ray diffraction (XRD) with Cu Kα radiation (λ = 1.5406 Å). In order to characterize the morphology of the samples, transmission electron microscopes (TEM, Philips EM208S 100 KV) and field emission scanning electron microscopes (FESEMs, Hitachi, Japan) were used. To measure absorbance from 200 to 800 nm, Uv/Vis spectrometer (Perkin Elmer Lambda 25) was used. In addition, a JASCO FT-IR-460 spectrometer was utilized to obtain Fourier transform infrared spectroscopy (FT-IR) in the 400 to 4,000 cm⁻¹ range. Using vibrating sample magnetometers (VSM), magnetic nanocomposites were measured at Mahamax, Tehran, Iran).