Matrix-assisted laser desorption/ionisation–time-of-flight mass spectrometry (MALDI–TOF MS) has already been used routinely in clinical laboratories for rapid bacterial and yeast identification. However, its routine use for Aspergillus identification is still controversial because of a lack of unification of the culture method and a suboptimal database. In this study, we first examined the difference in using broth and agar plate cultures for growing the aspergilli before protein extraction and found that agar culture was much superior to broth culture in generating interpretable protein mass spectra. Then, based on the solid culture method, we examined the accuracy, with benA and/or CaM sequencing as the identification gold standard, in using MALDI–TOF MS for Aspergillus identification. Overall, the original Bruker Library could only identify 38.2% and 22.8% of the strains characterised at the genus/section and species level, respectively. When the Bruker Library was expanded with reference mass spectra generated from reference Aspergillus species in-house, the identification rates were improved to 61.0% and 48.0%, respectively. The MSI database, freely available online, outperformed the former two libraries for Aspergillus identification at all levels (genus: 95.1%, section: 92.7%, species: 74.8%). Agar plate culture and the MSI database should be used for MALDI–TOF MS identification of aspergilli in clinical laboratories.
- Open Access
- Article
Identification of Aspergillus Species by Matrix-Assisted Laser Desorption Ionisation–Time-of-Flight Mass Spectrometry
- Chi-Ching Tsang 1,2,†,
- Walton Chan 2,†,
- James Y. M. Tang 2,
- Oscar H. Y. Chim 2,
- Yee-Wing Li 2,3,
- Teresa W. S. Hui 2,4,
- Tianrenzheng Zhu 2,5,
- Carl W. H. Leung 2,
- Caleb Lo 2,
- Chunyan Yao 2,6,
- Ying-Nam To 2,4,
- Antonio H. Y. Ngan 2,
- Jonathan H. K. Chen 2,
- Haiyan Ye 7,
- Fanfan Xing 7,
- Simon K. F. Lo 7,
- Chenlu Xiao 2,8,9,
- Lizhong Han 8,9,
- Dorothy M. W. Tam 3,
- Christopher K. C. Lai 10,
- Alan K. L. Wu 11,
- Tak-Lun Que 4,
- Susanna K. P. Lau 2,*,
- Patrick C.Y. Woo 2,12,13,*
Author Information
Received: 21 Nov 2025 | Revised: 16 Jan 2026 | Accepted: 20 Jan 2026 | Published: 01 Apr 2026
Abstract
Keywords
Aspergillus | rare species | cryptic species | MALDI–TOF MS | identification
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