An Efficient Detection Platform Based on Mesoporous Au@Cr₂O₃ Particles with Schwarz P Surface for Precise...

Matrix materials with high desorption and ionization efficiency are crucial for the sensitive and accurate metabolite profiling in matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). Herein, we develop an efficient detection platform based on Au nanoparticles decorated mesoporous Cr₂O₃ (Au@mCr₂O₃) particles with a single primitive continuous structure (i.e., Schwarz P surface) as the matrix. Owing to the low-tortuosity mesoporous pathways and customized chemical composition, the Au@mCr₂O₃ exhibits high-efficiency light absorption and electron transfer, showing great potential for sensitive, reproducible, and selective metabolite detection. Therefore, it is considered as a high-performance and reliable matrix material for metabolic biomarkers screening. As a proof of concept, the Au@mCr₂O₃-based detection platform decodes the saliva metabolic fingerprints. With the assistance of machine learning, the platform achieves high diagnostic performance for periodontitis, with the areas under the curve of 0.875-0.934. Furthermore, a simplified biomarker panel is established, which provides a deeper mechanism understanding of the metabolic alternation of periodontitis and offers new insights into its diagnosis and pathogenesis.