. Author manuscript; available in PMC: 2019 Aug 1.

Published in final edited form as: J Am Soc Mass Spectrom. 2018 Jun 12;29(8):1745–1756. doi: 10.1007/s13361-018-1999-6

Table 2.

Compilation of peaks m/z and RIAs of ions present in the HCD-based MS/MS spectra of positional isomers of methylated adenosines, guanosines and uridines acquired at CE 80, LC method 1, and 20 ng of nucleoside standard on column. m/z represented are based on theoretical calculations. RIAs are represented as mean (n=3), with RSD <10%.

m¹A		m²A		m⁶A		m⁸A		m¹G
Peak m/z	RIA	Peak m/z	RIA	Peak m/z	RIA	Peak m/z	RIA	Peak m/z	RIA
150.0780	100	150.0780	62	150.0780	100	151.0620	51	167.0569	100
133.0514	20	133.0514	100	123.0671	27	150.0780	100	166.0729	46
109.0514	20	92.0249	16	94.0405	23	133.0514	92	153.0412	67
						108.0562	17	149.0463	46
						106.0405	25	128.0460	22
								121.0514	16
								110.0354	15
								109.0514	17
								67.0296	15

m²G		m⁷G		m³U		m⁵U
Peak m/z	RIA	Peak m/z	RIA	Peak m/z	RIA	Peak m/z	RIA
167.0569	100	167.0569	100	127.0508	26	127.0508	47
149.0463	21	166.0729	38	96.0086	100	110.0242	100
128.0460	22	149.0463	49			109.0402	32
110.0354	22	124.0511	58			84.0449	34
57.0453	15					82.0293	27
						57.0340	16
						56.0500	22
						54.0340	39