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Bacterial infections already pose a significant threat to skin wounds, especially in diabetic patients who have difficulty healing wounds. However, wound or bacterial infections are known to produce excess reactive oxygen species (ROS), and hypoxia may further hinder wound healing and the development of chronic wounds. In this study, a multifunctional hydrogel for ROS scavenging and bacterial inhibition was developed by cross‐linking polyvinyl alcohol (PVA) and sodium alginate (SA) with graphene oxide (GO) loaded with silver‐platinum hybrid nanoparticles (GO@Ag‐Pt). The PVA/SA hydrogel loaded with GO@Ag‐Pt exhibited the ability to scavenge different types of ROS, generate O2, and kill a broad spectrum of bacteria in vitro. The silver‐platinum hybrid nanoparticles significantly increased the antibacterial ability against Escherichia coli and Staphylococcus aureus compared with silver nanoparticles (AgNps). GO@Ag‐Pt loaded hydrogel was effective in treating infections caused by S.aureus, thereby significantly promoting wound healing during the inflammatory phase. Hydrogel therapy significantly reduced the level of ROS and alleviated inflammation levels. Notably, our ROS‐scavenging, antibacterial hydrogels can be used to effectively treat various types of wounds, including difficult‐to‐heal diabetic wounds with bacterial infections. Thus, this study proposes an effective strategy for various chronic wound healing based on ROS clearance and bacteriostatic hydrogels. [ABSTRACT FROM AUTHOR]

In this work, we reported an effective method for the synthesis of a multirecognition magnetic molecularly imprinted polymer (MMIP) with atom transfer radical polymerization (ATRP), using 2,4-diamino-6-methyl-1,3,5-triazine as pseudo-template. The resulting MMIP was characterized in detail by Fourier transform-infrared (FT-IR) spectra, scanning electron microscopy (SEM), thermogravimetic analysis (TGA), and vibrating sample magnetometry (VSM). These results indicated the successful synthesis of MMIP with sufficient thermal stability and magnetic properties. The adsorption experiments were carried out to evaluate the specific selectivity of MMIP related to the spatial structure of target molecules. The MMIP exhibited multirecognition ability and excellent binding capability for melamine (MEL), cyromazine (CYR), triamterene (TAT), diaveridine (DVD), and trimethoprim (TME), and the apparent maximum number of binding sites ( Q ) was 77.5, 75.2, 72.5, 69.9, and 70.4 μmol g, respectively. The multirecognition MMIP not only possessed adequate magnetic responsiveness for fast separation but also avoided the risk of template leakage on trace component analysis. Therefore, it was suitable for serving as a magnetic solid-phase extraction (MSPE) adsorbent. MSPE coupled with high-performance liquid chromatography analysis was applied to enrich and separate five target molecules from three samples. Recoveries for all target molecules ranged from 81.6 to 91.5% with relative standard deviations of no more than 4.1% ( n = 3). [ABSTRACT FROM AUTHOR]

The effective method for trypsin purification should be established because trypsin has important economic value. In this work, a novel and simple strategy was proposed for fabricating micron-sized magnetic Fe 3 O 4 @agarose-benzamidine beads (MABB) with benzamidine as a ligand, which can efficiently and selectively capture trypsin. The micro-sized MABB, with clear spherical core-shell structure and average particle size of 6.6 μm, showed excellent suspension ability and magnetic responsiveness in aqueous solution. The adsorption capacity and selectivity of MABB towards target trypsin were significantly better than those of non-target lysozyme. According to the Langmuir equation, the maximum adsorption capacity of MABB for trypsin was 1946 mg g -1  at 25 °C, and the adsorption should be a physical sorption process. Furthermore, the initial adsorption rate and half equilibrium time of MABB toward trypsin were 787.4 mg g -1  min -1 and 0.71 min, respectively. To prove the practicability, MABB-based magnetic solid-phase extraction (MSPE) was proposed, and the related parameters were optimized in detail to improve the purification efficiency. With Tris-HCl buffer (50 mM, 10 mM CaCl 2 , pH 8.0) as extraction buffer, Tris-HCl buffer (50 mM, 100 mM CaCl 2 , pH 8.0) as rinsing buffer, acidic eluent (0.01 M HCl, 0.5 M NaCl, pH 2.0) as eluent buffer and alkaline buffer (1 M Tris-HCl buffer, pH 10.0) as neutralization solution, the MABB-based MSPE was successfully used for trypsin purification from the viscera of grass carp (Ctenopharyngodon idella). The molecular weight of purified trypsin was determined as approximate 23 kDa through sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The purified trypsin was highly active from 30 °C to 60 °C, with an optimum temperature of 50 °C, and was tolerant to pH variation, exhibiting 85 % of maximum enzyme activity from pH 7.0 to 10.0. The results demonstrated that the proposed MABB-based MSPE could effectively purify trypsin and ensure the biological activity of purified trypsin. Therefore, we believe that the novel MABB could be applicable for efficient purification of trypsin from complex biological systems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)