Identification of Polyamines in Human Milk, Formula Milk, and Other Dairy Products: a Special Method Based on Precolumn Derivatization, Double-Florisil Purification, and Gas Chromatography–Triple Quadrupole Mass Spectrometry

Polyamines in human milk are essential for the rapid growth and development of neonates and infants. However, the concentrations of polyamines in human milk have not been well characterized and the special methods for detecting polyamines in human milk, formula milk, or other dairy products remain largely unavailable to date. In this study, an accurate and sensitive method based on trifluoroacetic acid anhydride (TFAA) derivatization, double solid-phase extraction (SPE) purification, and gas chromatography–triple quadrupole mass spectrometry (GC-QqQ MS) was established for the evaluation of polyamines in human milk, formula milk, and other dairy products. High coefficients of determination for internal calibration curves were obtained (R2 > 0.99). Low limits of detection (5.0, 1.0, and 0.5 nmol/dL) and limits of quantification (10.0, 3.0, and 1.0 nmol/dL) for putrescine, spermidine, and spermine, respectively, were also achieved. The precision (expressed as relative standard deviation, RSD < 9.0%) and recovery rates (78.3–108.4%) were satisfactory. Spermidine and spermine in human milk were found significantly higher than those in formula milk and commercial cow’s milk. The difference of polyamine content in human milk and infant formula should be paid attention to, particularly when infant formula is used as a complete replacement for human milk.