Method for analyzing amino acids and/or acylcarnitines

A method for analyzing amino acids and/or acylcarnitines, comprising:

• setting, for each of one or more target substances each of which is an amino acid or an acylcarnitine, a first MRM transition and a second MRM transition each of which is a combination of a mass-to-charge ratio of a precursor ion and a mass-to-charge ratio of a product ion, as well as a first reference value concerning a measured intensity of the first MRM transition and a second reference value concerning a ratio between the measured intensity of the first MRM transition and a measured intensity of the second MRM transition;
• measuring, for each of the target substances, a first intensity which is the measured intensity of the first MRM transition and a second intensity which is the measured intensity of the second MRM transition, by performing an MRM measurement of an analyte sample using the first MRM transition and the second MRM transition set for each of the target substances;
• performing, for each of the target substances, a first determination in which a value of the first intensity is compared with the first reference value to determine whether or not the target substance concerned is possibly contained in the analyte sample;
• and
• performing, for a target substance considered to be possibly contained in the analyte sample in the first determination, a second determination in which the ratio between the value of the first intensity and a value of the second intensity is compared with the second reference value to determine whether or not the target substance concerned is contained in the analyte sample.