Irprestige 21 ftir 8400 spectrophotometer

FTIR spectra were obtained using Shimadzu IRPrestige-21 FTIR 8400 spectrophotometer (Kyoto, Japan). FTIR was used to characterize the presence of functional chemical groups in the materials. The synthesized MPIEDPCA, MPI was freeze-dried and mixed with KBr powder to form a pellet then the FTIR spectra were obtained in the range of 4000–400 cm⁻¹ using 64 scans.

The modification of the vicinal hydroxyl groups in inulin into aldehyde functional groups was confirmed by ¹H NMR (Bruker Avance III 500 NMR, Wissembourg, France) and FTIR spectrophotometer (Shimadzu IRPrestige-21 FTIR 8400 spectrophotometer, Kyoto, Japan). The FTIR spectra of all the oxidized samples and hydrogels were acquired using a Schimadzu FTIR spectrophotometer in the region of 4000−400 cm⁻¹ by recording 128 scans with a resolution of 4 cm⁻¹. Briefly, about 2 mg of the freeze-dried samples and hydrogels were ground into powder before being mixed with about 100 mg of KBr and pressed into pellets using a hydraulic press. The ¹H NMR spectra were acquired with a Brucker NMR spectrometer using a 5-mm broadband NMR probe, and DMSO was used as the solvent for all the samples except where stated otherwise.

About 2 mg each of dried raw inulin and the modified samples Oxi5, Oxi10, Oxi20, and Oxi30 samples with different degrees of oxidation was properly mixed with 100 mg of FTIR grade KBr powder to form a pellet; then, the FTIR spectra were obtained using a Shimadzu IR Prestige-21 FTIR 8400 spectrophotometer (Kyoto, Japan). All the spectra were obtained after 128 scans in the range of 4000–400 cm⁻¹.