Table 2. Summary of lipid species identified from the human urine using different extraction protocols.

Lipid species	m/z	Adduct ion	Protocol (i) C:M_1:1	Protocol (ii) C:M_2:1	Protocol (iii) Hex:IPA_3:2	Protocol (iv) CHCl3	Protocol (v) Ether	Protocol (vi) Hexane
SM16:0	703.7/725.7	[M + H]+/[M + Na]+	+++	+++	+++	++	0	0
SM22:0	787.8/809.7	[M + H]+/[M + Na]+	+++	++	+++	+	0	0
SM24:0	815.8	[M + H]+	+	++	+++	0	0	0
PC34:2	758.7	[M + H]+	++ +	+++	+++	+++	0	0
PC34:1	760.6	[M + H]+	+++	+++	+++	+++	0	0
PC36:4	782.6	[M + H]+	+++	+++	+++	+++	0	0
PC36:2	786.7	[M + H]+	+++	++	++ +	++	0	0
PE42:2	850.7	[M + H]+	0	0	0	0	+	+++
PG36:5	791.5	[M + Na]+	0	+	+	++	+++	+
PG38:8	813.4	[M + Na]+	+	+	+	+++	+++	+++
PG38:3	823.7	[M+Na]+	0	+	++	+++	+++	+
PG40:6	845.4	[M+Na]+	0	+++	+++	+	+++	+++
PG40:3	851.7	[M+Na]+	0	+	+	+	+++	++
PI32:2	829.4	[M+Na]+	+	+++	+++	+++	+++	+++
PI34:3	855.6	[M+Na]+	0	0	+	0	+	+++
PS40:1	868.7	[M+Na]+	0	0	++	++	++	0
PS42:8	882.6	[M+Na]+	0	0	0	++	+	++

+ = Detected in only one replicate.

++ = Detected in two replicates.

+++ = Detected in all three replicates.

0 = Undetectable.