Quantitative analysis of low molecular weight compounds of biological interest by matrix-assisted laser desorption ionization.

Internal standards were used to demonstrate that matrix-assisted laser desorption/ionization (MALDI) mass spectrometry can be applied to the quantitative analysis of low molecular weight polar compounds. Three examples were tested: a standard curve for 3,4-dihydroxyphenylalanine (DOPA) was prepared using a stable isotope analogue (i.e., [13C6]DOPA) as an… CONTINUE READING