This paper reports the study on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) of DNA, using 2, 4, 6-trihydroxyacetophenone (2, 4, 6-THAP) as matrix. The results show that 2, 4, 6-THAP has high efficiency in desorbing and ionizing DNA molecules: for [M-H]^- of d(T)~1~0, the resolution is 1130.0, the signal-to-noise ratio is 366.0, and the detection limit is 5×10^-^1^4mol; it can measure mix-based DNA with molecular weight higher than 14800. In order to improve desorption/ionization effects, the purification methods for DNA samples are established.

Key words: ACETOPHENONE P, NUCLEIC ACIDS, LASER, DESORPTION, TIME-OFF FLIGHT MASS SPECTROMETRY