Table 1. Retention times of the 14 standards.

Standard	Class	Concentration (μM)	Formula	m/z	RTs (min)
					HILIC	C5	C18
DG	Glycerolipid	10	C33H64O5	558.50972	2.16	24.95	n/a
Cer	Ceramide	2	C35H69NO4	568.53046	2.31	24.58	n/a
Ade	Nucleobase	40	C5H5N5	136.06232	11.17	2.32	2.16
Guo	Nucleoside	40	C10H13N5O5	284.09949	11.58	2.27	2.16
PG	GlyceroPhospholipid	10	C40H78O10P	768.57542	12.08	24.58	n/a
PA	GlyceroPhospholipid	10	C37H73O8P	694.53865	12.82	24.86	n/a
PE	GlyceroPhospholipid	10	C39H78NO8P	720.55430	13.50	24.86	n/a
Cr	Amino acid	40	C4H7N3O	114.06673	13.90	2.27	2.16
Suc	Sugar	40	C12H22O11	360.15058	14.09	2.27	2.05
PC	GlyceroPhospholipid	10	C42H84NO8P	762.60125	14.71	24.95	n/a
Phe	Amino acid	40	C9H11NO2	166.08680	15.03	2.32	2.26
LysoPC	GlyceroPhospholipid	10	C25H52NO7P	510.35595	15.72	22.94	n/a
Arg	Amino acid	40	C6H14N4O2	175.11950	18.75	2.23	2.05
His	Amino acid	40	C6H9N3O2	156.07730	18.97	2.23	2.05