MALDI-TOF mass spectrometry applied for animal species identification based on bone samples

The present study aims at developing a strategy to analyze bone samples in a rapid and facile mode. An efficient treatment method was found to be heating a material ratio of 0.5 g bone samples in 5 mL formic acid aqueous solution (10%, v/v) at 95 °C for at least 5.2 min, followed by a 50-fold dilution for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis. Principal component analysis (PCA) was used to analyze the obtained mass spectral datasets. Eight animal-sourced bones were analyzed as models. The extracts from these animal-sourced bones can be utilized to classify fish at species level with >90% accuracy. Domestic chicken and porcine bone samples were analyzed to verify whether this method can be applied for judicial authentication. The obtained results indicated that the developed strategy could differentiate samples by analyzing their bones via MALDI-TOF MS and PCA, holding a great potential for animal species monitoring including raw fish and meats and for judicial authentication.