Harnessing chemical functionality of xylan hemicellulose towards bio-based pH/magnetic dual-responsive nanocomposite hydrogel for drug delivery

Abstract This study reports for the first time an innovative pH/magnetic dual-responsive hemicellulose-based nanocomposite hydrogel with a nearly 100% bio-based and biodegradable compositions. We synthesized pure Fe3O4 magnetic nanoparticles (Fe3O4 MNPs) using co-precipitation, then engineering xylan hemicellulose (XH), acrylic acid (AA), polyethylene glycol diacrylate (PEGDA), and Fe3O4 MNPs to synthesize the pH/magnetic dual-responsive hydrogel (Fe3O4@XH-Gel), through free radical graft polymerization on natural XH with in-situ doping Fe3O4 MNPs initiated by the ammonium persulfate/tetramethylethylenediamine (APS/TMEDA) redox system. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H-NMR), X-ray diffractometry (XRD), scanning electron microscopy and energy dispersive spectrometer (SEM-EDS), Brunauer-Emmett-Teller (BET), dynamic light scattering (DLS), swelling gravimetric analysis, vibrating sample magnetometer (VSM) were employed to analyze the hydrogel’s chemical structures, surface morphologies, pH-responsive behaviors, and magnetic responsiveness characteristics. The results indicate that the Fe3O4@XH-Gel nanocomposite hydrogel exhibited excellent dual responsiveness to pH and magnetism. Furthermore, an emphasis was placed on the in-depth analysis of the pH response mechanism and drug release control. Finally, we utilized this cutting-edge hydrogel to investigate the controlled-release behavior of two model drugs, Acetylsalicylic acid and Theophylline, within the simulated gastrointestinal tract. The Fe3O4@XH-Gel nanocomposite hydrogel demonstrated exceptional controlled release attributes, positioning it as a potential carrier for targeted drug delivery, particularly to the gastrointestinal conditions.