Metal–organic gel (MOG) is a distinctive metal–organic hybrid material with a unique porous structure and exceptional catalytic site accessibility. The rational design of an electrochemical and colorimetric dual-mode sensor platform utilizing the peroxidase (POD)-like activity of MOG for the detection of H2O2 is crucial for clinical diagnosis. In this article, a two-dimensional composite nanozyme based on Fe-MOG and carboxylated graphene oxide (GO-COOH) was synthesized, which serves dual functions to establish electrochemical sensing and colorimetric sensing based on its excellent electrocatalytic reduction of H2O2 and POD-like activity. GO-COOH played a critical role, and the electrochemically reduced ERGO-COOH facilitated electron transfer from the metal catalytic site in Fe-MOG, enhancing the performance of electrocatalytic reduction of H2O2. Additionally, GO-COOH amplified the POD-like activity of Fe-MOG, and the Fe-MOG/GO-COOH composite participated in various ROS-mediated catalytic reactions. The developed dual-mode sensor exhibited a rapid response and high sensitivity in detecting H2O2, demonstrating excellent selectivity, reproducibility, and stability. These attributes enhanced the accuracy and reliability of the detection of H2O2 released from living cells. This MOG-based nanozymatic dual-mode sensing technology offers promising prospects for enhancing the reliability of rapid detection and holds significant potential for application in pathophysiological monitoring of living cells.
Waste Shatian pomelo peel was converted into a cellulose aerogel precursor. • An Fe-based MOG/cellulose carbon aerogel was fabricated by in situ growth. • The aerogel enabled efficient oxytetracycline adsorption and magnetic recovery. • The biobased adsorbent showed good recyclability and regeneration stability. Biomass aerogels often face a trade-off between adsorption capacity and recoverability in antibiotic removal. To address this limitation, Shatian pomelo peel, an abundant agricultural byproduct from pomelo processing, was used as a cellulose precursor to fabricate a pomelo peel-derived porous cellulose material (PPCM). An Fe-based metal-organic gel (MOG) was introduced in situ as an Fe-containing precursor, followed by high-temperature carbonization to prepare an Fe-MOG-derived magnetic carbon aerogel (FMCA) containing Fe species, a well-developed porous structure, and magnetic responsiveness. After response surface optimization, the resulting FMCA achieved an adsorption capacity of 836.1 mg g −1 for oxytetracycline (OTC) at an initial concentration of 100 mg L −1 and exhibited a saturation magnetization of 50.28 emu g −1 , enabling rapid magnetic separation under an external magnetic field. After five adsorption-desorption cycles, the material retained approximately 70% of its initial adsorption capacity. The kinetic and isotherm data were best described by the pseudo-second-order and Langmuir models, respectively. Combined pore-structure, zeta-potential, FT-IR, XPS, and batch adsorption results indicated that OTC uptake involved pore filling and multiple interfacial interactions. These results demonstrate that coupling in situ Fe-based MOG incorporation with carbonization is an effective strategy for simultaneously improving adsorption efficiency and recoverability in pomelo peel-derived aerogels, offering a promising route for agricultural byproduct valorization and antibiotic-contaminated water treatment. Download: Download high-res image (293KB) Download: Download full-size image
危险品化学品经营许可证（带存储）