Quantification of Salivary Charged Metabolites using Capillary Electrophoresis Time-of-flight-mass Spectrometry

Masahiro Sugimoto; Sana Ota; Miku Kaneko; Ayame Enomoto; Tomoyoshi Soga

doi:10.21769/BioProtoc.3797

Quantification of Salivary Charged Metabolites using Capillary Electrophoresis Time-of-flight-mass Spectrometry

Bio Protoc. 2020 Oct 20;10(20):e3797. doi: 10.21769/BioProtoc.3797.

Authors

Masahiro Sugimoto^{1

2}, Sana Ota², Miku Kaneko², Ayame Enomoto², Tomoyoshi Soga²

Affiliations

¹ Research and Development Center for Minimally Invasive Therapies, Institute of Medical Science, Tokyo Medical University, Tokyo, Japan.
² Institute for Advanced Biosciences, Keio University, Yamagata, Japan.

Abstract

Salivary metabolomics have provided the potentials to detect both oral and systemic diseases. Capillary electrophoresis time-of-flight-mass spectrometry (CE-TOFMS) enables the identification and quantification of various charged metabolites. This method has been employed to biomarker discoveries using human saliva samples, especially for various types of cancers. The untargeted analysis contributes to finding new biomarkers. i.e., the analysis of all detectable signals including both known and unknown metabolites extends the coverage of metabolite to be observed. However, the observed data includes thousands of peaks. Besides, non-linear migration time fluctuation and skewed peaks are caused by the sample condition. The presented pretreatment protocols of saliva samples enhance the reproducibility of migration time drift, which facilitates the matching peaks across the samples and also results in reproducible absolute concentrations of the detected metabolites. The described protocols are utilized not only for saliva but for any liquid samples with slight modifications.

Keywords: Cancer; Capillary electrophoresis-mass spectrometry; Metabolomics; Polyamine; Saliva.