Abstract: A Study on the Benzylquinone Idebenone by FABMSYu Zhili (Institute of Medicinal Biotechnology, Chinese Academy of Medicsl Sciences,Beijing 100050,China) Abstract:The quasi-moleculer ion of benzylquinone idebenone was measured. It is (M+2H)~+ in the glycerol matrix,but(M+H)~+ in the 3-nitrobenzyl alcohol (NBA)matrix. It probably resulted from the hydroquinol in the glycerol matrix of the FAB source. Keywords: benzylquinone, idebebenone, quasi-moleculer ion, matrix, glycerol, NBA, hydroquinol