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Updated: Jan 21, 2026

Scalable Syntheses of Graphene Oxide and Reduced Graphene Oxide using Cascade Design Oxidation and Highly Basic Reduction Reactions
Published on: July 3, 2025
Preparation of porous aromatic framework modified graphene oxide for pipette-tip solid-phase extraction of
Qilin Deng1, Liping Sun1, Tao Zhu1
1Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin, P. R. China.
Abstract:
A new material called as porous aromatic frameworks modified graphene oxide (PAFs-GO) was synthesized, and it was used as an adsorbent in pipette-tip SPE for the effective purification and enrichment of theophylline in tea sample by HPLC. The properties of PAFs-GO were characterized by field emission SEM, FTIR, thermogravimetry analysis and Brunauer Emmett Teller N2 adsorption-desorption analysis. The results of static adsorption and dynamic adsorption test showed PAFs-GO had higher adsorption ability (93.25 mg/g) than graphene oxide. The LOD and LOQ of the method were 0.0141 and 0.0471 µg/mL, respectively. The acceptable method reproducibility was found as intra- and inter-day precisions, yielding the RSDs <4.62%. By introducing PAFs as support skeleton, the specific surface area of GO was effectively increased, and the penetrability was improved. Studies showed that the proposed method had been successfully applied for purification and enrichment of theophylline in complex tea matrix.
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