Table 2. Proposed structures and their molecular ions in MALDI spectra of N-glycans in the four cell lines.

No.	Calculated m/z	Relative intensity				Glycan structure	Calculated m/z (acetyl hydrazine modification)	Glycan structure (sialic)
		GES-1	SGC-7901	HGC-27	MGC-803
1	1257.423	0.048±0.001	0.024±0.002	0.078±0.045	0.018±0.009		-	-
2	1419.476	0.189±0.001	0.352±0.080	0.294±0.142	0.172±0.008		-	-
3	1565.533	-	0.020	0.021	0.026±0.003		-	-
4	1581.528	0.245±0.035	0.365±0.052	0.307±0.023	0.351±0.008		-	-
5	1622.555	-	-	0.021	0.025±0.018		-	-
6	1663.581	-	0.104±0.011	0.048	0.023±0.014		-	-
7	1688.613			0.082±0.025
8	1743.581	1.000	1.000	1.000	1.000		-	-
9	1809.639	0.059±0.022	0.624±0.046	0.199±0.044	0.043±0.0004		-	-
10	1850.666	-	-	0.054±0.041	-		-	-
11	1865.654	-	0.076±0.074	0.039±0.030	-		-	-
12	1905.634	0.382±0.106	0.438±0.066	0.724±0.050	0.476±0.003		-	-
13	1955.697	0.048±0.025	0.294±0.142	0.020	-		-	-
14	1996.724	-	-	0.018	-		-	-
15	2012.719	-	0.032±0.021	0.078±0.026	0.048		-	-
16	2028.714		0.054±0.015	0.041±0.006	-		-	-
17	2067.687	0.043±0.007	0.045±0.007	0.083±0.005	0.044±0.003		-	-
18	2101.755	-	0.053±0.038	-	-		2047.713
19	2174.772	0.036±0.020	0.199±0.072	0.216±0.089	-		-	-
20	2215.798	-	-	0.021±0.007	-		2157.756
21	2231.793	-	0.020±0.016	0.026±0.018	-		-	-
22	2247.813	-	0.015	-	-		-	-
23	2320.829	-	0.051±0.038	-	-		2262.788
24	2377.851	-	0.010±0.001	0.038±0.003	-		-	-
25	-	-	0.069	0.020	-		2319.809
26	2393.846		0.036±0.0002
27	2466.887	-	0.028	-	-		-	-
28	2539.904	-	0.214±0.077	0.147±0.048	-		-	-
29	-	-	0.017±0.014	0.015±0.012	-		2538.908
30	2612.945	-	0.009	-	-		-	-
31	2685.962	-	0.036±0.027	-	-		-	-
32	2758.978	-	0.006±0.001	-	-		-	-
33	2832.02	-	0.013	-	-		-	-
34	2905.036	-	0.011±0.003	0.020±0.006	-		-	-
35	-	-	0.006	-	-		2993.052

N-glycans with SD were identified in two independent experiments, and N-glycans without SD were identified in only one experiment.