Avance 250 mhz spectrometer

Gel-H.P dialyzed for 24 h against distilled water and then lyophilized. The lyophilized hydrogel dissolved in D₂O and was applied for NMR analysis using a Bruker Avance 250 MHZ spectrometer. Gel-H.P.Cur was immersed in DMSO for 48 h and then the NMR of released curcumin in DMSO was studied.The NMR data was processed using MestReNova software.

All reagents were purchased from Sigma-Aldrich (St. Louis, MO, USA), Alfa Aesar (Lancaster, UK) and TCI (Tokyo, Japan) and used without further purification. NMR spectra were recorded with a Bruker Avance 500 MHz spectrometer (Bruker, Rheinstetten, Germany) operating at 500 MHz (¹H) and 125 MHz (¹³C) or with a Bruker Avance 250 MHz spectrometer (Bruker, Rheinstetten, Germany) operating at 250 MHz (¹H) and 62.5 MHz (¹³C). Chemical shifts are reported in ppm relative to DMSO-d₆ (¹H: δ = 2.50 ppm, ¹³C: δ = 39.52 ± 0.06 ppm). Elemental analyses were performed using a PerkinElmer 2400 CHNS 100V Organic Elemental Analyzer (Waltham, MA, USA). Compounds 5–7 were synthesised as described previously [27 (link),28 (link),29 (link)].

All materials and reagents were purchased from chemical sources and used as received. The Fourier transform infrared spectroscopy (FT-IR) was performed using a Bruker Vertex 70 FT-IR spectrometer. ¹H and ¹³C NMR spectra were recorded using a Bruker Avance 250 MHz spectrometer. The powder X-ray diffractometry (XRD) patterns were obtained using an X'Pert Pro Panalytical diffractometer applying a 30 mA current and a 40 kV voltage with Cu-Kα radiation (λ = 1.5418 Å). The morphology and size of the prepared nanoparticles were investigated using SEM images obtained from the FESEM-TESCAN MIRA3 instrument. Nanocatalysts' chemical composition was determined by EDX using SEM analysis. The specimen's magnetic susceptibility was determined via a vibrating sample magnetometer (Meghnatis Daghigh Kavir, Co. Iran) in a magnetic field of 20 kOe. Thermogravimetric analysis (TGA) was performed using the Shimadzu DTG-60 device at 0 to 700 °C. In addition, thin-layer chromatography (TLC) analysis was performed to determine the products' purity and monitor the reaction progress in a silica gel 60 F254 aluminum sheet.