Bacterial infection caused by trauma and chronic wounds in the most mobile area remains a challenge in clinic. It is difficult to achieve the synergistic effects of antibacterial capacity and skin regeneration using conventional therapeutic methods. Developing a multi-functional hydrogel dressing that can cope with the complex wound environment will contribute to the healing and therapeutic effects. In this work, a novel Cur@PAM/TA-Cu photothermal hydrogel delivery system was prepared by engineering tannic acid (TA) into covalent cross-linked polyacrylamide (PAM) on which the chelating tannic acid-copper metal–polyphenolic network (TA-Cu MPN) was imposed to form dual-crosslinked networks, and the natural medicine curcumin was loaded eventually. The molecularly engineered dual-crosslinked networks resulted in enhanced mechanical properties including bio-adhesion, tensile strength and self-healing, which made the hydrogel suitable for dynamic wound and various application scenarios. In addition, the excellent photothermal capacity, antioxidant effect and biocompatibility of the hydrogel were demonstrated. Notably, this curcumin loaded photothermal hydrogel exhibited superior antibacterial capacity (almost 100% killing ratio to E . coli and S . aureus) under 808 nm laser irradiation . Meanwhile, the in vivo wound healing experiment results revealed that the anti-inflammation and proangiogenic effect of Cur@PAM/TA-Cu hydrogel successfully shortened the healing time of wound and the reconstruction of skin structure and function. Thus, this dual-crosslinked multi-functional hydrogel delivery system is a promising wound dressing for accelerating wound healing.
Mingliang Luo,Xiaodong Si,Mingzhong Li,Yige Huang,Qinpeng Li,Changheng Li
In this study, we designed a magnetic responsive hydrogel, also known as magnetorheological gel (MRG), based on a carbonyl iron particle@polyacrylamide (CIP@PAM) composite and a water-soluble PAM matrix to use as a temporary plugging agent (TPA) in the hydraulic fracturing of unconventional hydrocarbon reservoirs. The CIP@PAM composite was synthesized and characterized by Fourier transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM), laser particle size analysis (LPSA) and vibrating sample magnetometry (VSM). The results show that a thin and uniform PAM layer was successfully coated on the surface of the CIPs, which plays a key role in enhancing the antioxidant capacity of the CIPs. Meanwhile, the CIP@PAM composite possesses a high saturation magnetization (148.8 emu/g). MRG as a TPA has a high gel strength and magnetorheological effect under a magnetic field intensity of 1 T, providing a breakthrough pressure up to 38.13 MPa at room temperature . Compared with the conventional temporary plugging agent, MRG as the temporary plugging agent possesses high magnetic responsiveness to easily control, good degradability and recyclability, providing great potential application in hydraulic fracturing.