Ft ir 400 spectrometer

Optical rotation data were recorded on a PerkinElmer model 341 polarimeter with a 10 cm length cell at room temperature. UV and IR (KBr) spectra were obtained on a Hitachi U-3010 spectrophotometer and Jasco FTIR-400 spectrometer, respectively. CD spectra were obtained on a Jasco J-715 spectropolarimeter in MeCN. NMR spectra including 1D and 2D spectra were acquired at room temperature on Bruker AMX-500 instrument. HRESIMS data were obtained on a Waters Q-Tof micro YA019 mass spectrometer. Reversed-phase HPLC was performed on YMC-Pack Pro C18 RS (5 μm) columns with a Waters 1525 separation module equipped with a Waters 2998 photodiode array detector. Purifications by column chromatography were performed on silica gel 60 (200–300 mesh; Yantai, China), Sephadex LH-20 (18–110 μm, Pharmacia Co.), and ODS (50 μm, YMC Co.). Analytical thin-layer chromatography was carried out using HSGF 254 plates and visualized by spraying with anisaldehyde-H₂SO₄ reagent.

Fourier Transform Infrared Spectroscopy (FT-IR) was used to characterise the presence of specific chemical groups in the hydrogels. Each sample (control and loaded hydrogels) was analysed using an FT/IR-400 spectrometer (Jasco Corporation, Kyoto, Japan). A total of 128 scans were obtained for each measurement at a resolution of 4 cm⁻¹. The FT-IR spectra of the samples were recorded at wavelengths ranging from 1200 to 950 cm⁻¹. The resulting starch-averaged spectrum was smoothed to remove any potential noise using a fifteen-point adaptive smoothing function. Subsequently, the baseline modification and a normalised function were applied.

Optical rotations were measured with an Autopol I-30575 (l = 10 cm) and UV spectra on a Hitachi U-3010 spectrophotometer; IR spectra (KBr) were obtained with a Jasco FTIR-400 spectrometer, whereas ECD spectra were obtained on a Jasco J-810 spectropolarimeter. NMR spectra were obtained with a Bruker Avance NMR spectrometer at 600 MHz for ¹H and 150 Hz for ¹³C using Pyr-d₅ as solvent. HRESIMS data were obtained on an Agilent 6210 LC/MSD TOF mass spectrometer.