3‐aminopicolinic aid as a matrix for laser desorption mass spectrometry of biopolymers

Abstract
3‐Aminopicolinic acid (3‐APA) was tested and found to be a useful matrix for matrix‐assisted laser desorption/ionization of DNA and protein. Single‐stranded DNA segments of 150‐mer and double‐stranded DNA of 246 base pairs were successfully detected by using 3‐APA as an ultraviolet‐absorbing matrix in a linear time‐of‐flight mass spectrometer. In the case of the double‐stranded DNA, only parent ions corresponding to single‐stranded DNA were observed. The comparison with 3‐hydroxypicolinic acid and picolinic acid matrices is discussed.