Enrichment and characterization of foodborne fungal spores by ferric ion-based surface-assisted laser desorption/ionization mass spectrometry

Tzu-Ling Yang; Chih-Wei Chen; Noor Hidayat Abu Bakar; Pin-Chen Pan; Po-Hung Cheng; Yu-Chie Chen

doi:10.1016/j.foodchem.2024.142301

Enrichment and characterization of foodborne fungal spores by ferric ion-based surface-assisted laser desorption/ionization mass spectrometry

Food Chem. 2025 Mar 1:467:142301. doi: 10.1016/j.foodchem.2024.142301. Epub 2024 Nov 30.

Authors

Tzu-Ling Yang¹, Chih-Wei Chen¹, Noor Hidayat Abu Bakar², Pin-Chen Pan¹, Po-Hung Cheng¹, Yu-Chie Chen³

Affiliations

¹ Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan.
² Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan.
³ Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan; International College of Semiconductor Technology, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan. Electronic address: yuchie@nycu.edu.tw.

PMID: 39647381
DOI: 10.1016/j.foodchem.2024.142301

Abstract

We developed a novel surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) method to detect fungal spores, which is a critical concern in food safety. A combination of Fe³⁺ and trifluoroacetic acid (TFA) was initially confirmed as an effective light absorber, facilitating the desorption and ionization of small organics in SALDI-MS. This approach was then successfully applied to the analysis of small organics derived from Aspergillus niger, aflatoxigenic Aspergillus flavus, and non-aflatoxigenic A. flavus, enabling the differentiation of closely related species and strains. Additionally, Fe³⁺ and Gd³⁺ were used as magnetic probes to trap and concentrate spores from sample solutions, and TFA-mediated lysis and SALDI-MS analysis were performed. We demonstrated that the proposed method can be used to trap trace amounts of fungal spores in a peanut extract and complement Fe³⁺-SALDI MS analysis. The limit of detection of the method against fungal spores was as low as ∼10⁴ spores mL^-1.

Keywords: Aspergillus flavus; Aspergillus niger; Biomarkers; Enrichment; Ferric ions; Fungi; Gadolinium ions; Magnetic probe; SALDI-MS.

Publication types

Evaluation Study

MeSH terms

Arachis / chemistry
Arachis / microbiology
Aspergillus flavus / chemistry
Aspergillus flavus / isolation & purification
Aspergillus flavus / metabolism
Aspergillus niger / chemistry
Aspergillus niger / isolation & purification
Ferric Compounds / chemistry
Food Contamination* / analysis
Food Microbiology
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization* / methods
Spores, Fungal* / chemistry

Substances

Ferric Compounds