Evaluation of Gas Explosion Injury Based on Analysis of Rat Serum Profile by Ultra-Performance Liquid Chromatography/Mass Spectrometry-Based Metabonomics Techniques

Table 1

Potential biomarkers identified in positive ion mode in rat serum.

Retention time (min)	Measured ion (Da)	Calculated ion (Da)	Exact mass	Mass error (PPM)	Elemental composition	Postulated identity	Scan mode	VIP values	KEGG	Trend in exposure groups	RSD
1.56	176.1030	176.1030	175.1858	0	C6H13N3O3	Citrulline^a,b	[M+H]+	2.0919	C00327	↓	0.03%
1.34	147.1128	147.1128	146.1876	1	C6H14N2O2	L-Lysine^a,b	[M+H]+	2.0666	C00047	↑	0.02%
2.35	150.0584	150.0576	149.2123	5	C5H11NO2S	L-Methionine^a,b	[M+H]+	1.9141	C00073	↑	0.05%
2.34	139.0502	139.0495	138.1241	5	C6H6N2O2	Urocanic acid^a,b	[M+H]+	1.7809	C00785	↑	0.07%
1.70	162.0761	162.0756	161.1559	3	C6H11NO4	2-Aminoadipic acid^a,b	[M+H]+	1.7341	C00956	↑	0.03%
1.53	120.0657	120.0653	119.1192	4	C4H9NO3	L-Threonine^a,b	[M+H]+	1.6720	C00188	↑	0.02%
5.83	166.0863	166.0860	165.1892	3	C9H11NO2	L-Phenylalanine^a,b	[M+H]+	1.6682	C00079	↑	0.02%
1.52	147.0764	147.0765	146.1446	0	C5H10N2O3	L-Glutamine^a,b	[M+H]+	1.6528	C00064	↓	0.03%
13.61	450.3212	450.3200	449.6234	3	C26H43NO5	Glycochenodeoxycholic acid^a,b	[M+H]+	1.4590	C05466	↓	0.04%

^aIons identified by comparison to the standard chemicals. ^bBiomarkers identified by the Human Metabolome Database (HMDB) and confirmed using exact mass data and MS fragmentation. VIP: variable importance in projection; RSD: relative standard deviation.