主权项 |
1. A Matrix-Assisted Laser Desorption/Ionization mass spectrometry substrate, comprising a support that includes an array of spots, some or all of which spots comprise:
(i) a matrix material for Matrix-Assisted Laser Desorption/Ionization mass spectrometry of nucleic acids, wherein the matrix material is selected from among 3-hydroxypicolinic acid, di-ammoniumcitrate or a mixture of 3-hydroxypicolinic acid and di-ammoniumcitrate and; (ii) an additive that comprises ascorbic acid, or a salt, tautomer or analog thereof, in an amount that reduces the amount of an adduct formed under Matrix-Assisted Laser Desorption/Ionization mass spectrometry conditions, wherein the analog of ascorbic acid is according to the following formula: wherein: R1 and R2 independently are OH, halogen, R3, OR3, azido, cyano, CH2R3, CHR3R4, SR3, NR3R4; and R3 and R4 independently are H, alkyl, acetylene or cyano, or an optionally substituted aryl carbocyclic ring, aryl heterocyclic ring, non-aryl carbocyclic ring or non-aryl heterocyclic ring. |