Nanoparticle microarray for high-throughput microbiome metabolomics using matrix-assisted laser desorption ionization mass spectrometry

• Published in: Analytical and bioanalytical chemistry 2019, Vol.411 (1), p.147-156
• Main Authors: Hansen, Rebecca L., Dueñas, Maria Emilia, Looft, Torey, Lee, Young Jin
• Format: Article
• Language: English
• Subjects: Acetic acid; Additives; Analytical Chemistry; Antibiotics; Bacitracin; Biochemistry; Bone mineral density; Cecum; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Copper; Desorption; Food Science; Intestinal microflora; Intestine; Ionization; Ions; Iron oxides; Laboratory Medicine; Liquid chromatography; Mass spectrometry; Mass spectroscopy; Matrix; Metabolites; Metabolomics; Methods; Microbiomes; Monitoring/Environmental Analysis; Nanoparticles; Negative ions; Organic chemistry; Paper in Forefront; Positive ions; Scientific imaging; Silver; Sodium acetate; Spectroscopy; Statistical analysis; Statistical methods
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-018-1436-5

A high-throughput matrix-assisted laser desorption/ionization mass spectrometry (MALDI)-MS-based metabolomics platform was developed using a pre-fabricated microarray of nanoparticles and organic matrices. Selected organic matrices, inorganic nanoparticle (NP) suspensions, and sputter coated metal NPs, as well as various additives, were tested for metabolomics analysis of the turkey gut microbiome. Four NPs and one organic matrix were selected as the optimal matrix set: α-cyano-4-hydroycinnamic acid, Fe 3 O 4 and Au NPs in positive ion mode with 10 mM sodium acetate, and Cu and Ag NPs in negative ion mode with no additive. Using this set of five matrices, over two thousand unique metabolite features were reproducibly detected across intestinal samples from turkeys fed a diet amended with therapeutic or sub-therapeutic antibiotics (200 g/ton or 50 g/ton bacitracin methylene disalicylate (BMD), respectively), or non-amended feed. Among the thousands of unique features, 56 of them were chemically identified using MALDI-MS/MS, with the help of in-parallel liquid chromatography (LC)-MS/MS analysis. Lastly, as a proof of concept application, this protocol was applied to 52 turkey cecal samples at three different time points from the antibiotic feed trial. Statistical analysis indicated variations in the metabolome of turkeys with different ages or treatments. Graphical abstract ᅟ