A tunable LDI-MS platform assisted by metal-phenolic network-coated AuNPs for sensitive and customized detection of amino acids

• Published in: Talanta (Oxford) Vol. 281; p. 126928
• Main Authors: Hu, Tong, Sang, Qi, Liang, Dingyitai, Zhang, Wenjing, Wang, Yuning, Qian, Kun
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2025
• Subjects: Amino acid; AuNPs; Histidine detection; LDI-MS; Metabolite; Metal-phenolic network; Metal-phenolic network; LDI-MS; Amino acid; Metabolite; Histidine detection; AuNPs
• ISSN: 0039-9140; 1873-3573; 1873-3573
• DOI: 10.1016/j.talanta.2024.126928

This study introduces a novel approach for the sensitive and accurate detection of small molecule metabolites, employing metal-phenolic network (MPN) functionalized AuNPs as both adsorbent and matrix to enhance laser desorption/ionization mass spectrometry (LDI-MS) performance. The MPN comprising tannic acid (TA) and transition metal ions (Fe3+, Co2+, Ni2+, Cu2+, or Zn2+) was coated on the surface of AuNPs, forming metal-TA network-coated AuNPs (M-TA@AuNPs). The M-TA@AuNPs provided a tunable surface for specific interactions with analytes, displaying distinct enrichment efficacies for different amino acids, especially for Cu-TA@AuNPs exhibiting the highest affinity for histidine (His). Under the optimized condition, the proposed method enabled ultrasensitive detection of His, with good linearity (R2 = 0.9627) in the low-concentration range (50 nM-1 μM) and a limit of detection (LOD) as low as 0.9 nM. Furthermore, the method was successfully applied to detect His from human urine samples, showcasing its practical applications in clinical diagnostics, particularly in the realm of amino acid-based targeted metabolomics. [Display omitted] •A series of metal-phenolic network functionalized AuNPs (M-TA@AuNPs) were synthesized in a facile and green way.•The prepared M-TA@AuNPs served as LDI-MS matrices exhibiting improved performance for detection of small metabolites.•M-TA@AuNPs as adsorbents can enrich low-abundance amino acids for enhanced sensitivity.•By varying metal ions, M-TA@AuNPs displayed distinct affinities for different analytes.