Table 1.

SERS peak positions and tentative assignments of the different cell-derived exosomes.

Raman Shift/cm−1								Assignments
EC109	EC9706	Kyse150	MCF7	M231	M10A	HepG2	L02
	540		547	546	546	546	536	Cholesterol [12], C-S stretching [23]
		558	556		557	557	556	Glycogen [26]
570	570		574	574		574		C=S tensile vibration, Glycogen [26]
628	628	628	627	629	636	629	628	Deformation vibration of adenine ring, phenylalanine C-C torsional vibration [22]
654	654	652		658		660	654	Tyrosine vibration, Guanine [27]
			686		680		687	Tyrosine, phenylalanine [26]
723	725					727		Adenine respiratory vibration, nucleotides [23], C-N symmetric stretching band (phospholipid) [22]
		732	735	735	735	735	735	Adenine [22,23]
742			754		749		755	Lactic acid [14,28], DNA, nucleic acids [23], symmetric breathing of tryptophan [22]
829	826	828	828	826	822	829		Sugar–phosphate backbone vibration [27], protein [28], C-O-O vibration typical of phospholipids [29],
			855	870	854	852	847	Cholesterol, oxyproline, tryptophan, glycogen [28], C-C stretch proline ring in collagen [22]
						873	874	Tryptophan, CH2 deformation (e.g., protein) [25,30]
914		917	920	921	919	920	914	C=C stretching vibration, proline [24]
961	960	962	963	964	967	964	964	Adenine, C-N deformed vibration, carbohydrates [24]
999	1001	1001	999	998	998	998	998	symmetric respiratory vibration of phenylalanine [23]
					1015			C–O vibration in DNA/RNA, C–C vibration [24]
	1029		1032	1032	1031	1031	1028	CH2CH3 bending (e.g., phospholipid); C-C vibration (e.g., polysaccharide) [25]
							1055	Glycogen [28]
					1067	1071		C-C vibrations in lipid and protein [2], C–O vibration in DNA/RNA [24], collagen [26]
1093	1093							Phosphate: PO2− vibration, C-C vibration, C-O-C vibration, glycoside link [24]
							1115	C-O ribose (e.g., nucleic acid) [30], O–P–O DNA backbone [27], C-N vibration [24]
1127	1129				1130			C-C vibrations in lipid [12,22], C-N stretching vibration in protein [22],
		1137		1136		1136		Proline [24]
			1150		1143		1148	CH vibration in protein [31], ribose-phosphate [24]
		1167	1168	1168	1167			Carotenoids [31], CH deformation in protein [30], Ribose-phosphate [24]
					1221			Amide III [24]
1225						1229	1229	Lipids, protein [28], cytosine [24]
1240	1241		1246	1250		1247	1243	Amide III [24], asymmetric phosphate stretching (e.g., nucleic acid) [25]
					1264			Amide III (e.g., protein), C=C (e.g., fatty acids) [24,25,28]
1310	1314	1318	1320	1318	1317	1318	1318	Amide III, CH deformation, CH3CH2 wagging (e.g., nucleic acids, collagen) [25], guanine [22,24],
			1352	1350	1351	1351	1354	Guanine (nucleic acid) [12], CH2, CH3 wagging in protein [24]
						1368		CH3 vibration (e.g., phospholipid) [12]
1370	1373	1373	1376	1376	1374		1376	Carbohydrate [12], adenine, guanine, thymine [24]
1457	1458	1458			1453		1451	CH2CH3 asymmetric and symmetric deformations in proteins, phospholipid and DNA [22,26]
			1469	1473		1470	1475	Adenine, C-N stretching, CH deformation (e.g., lipid, protein) [32]
					1532		1532	Vibration of (-C=C-) conjugated [25]
				1558	1562	1556	1562	Tryptophan [12]
1586	1585		1581	1580	1573	1580		Guanine [22], adenine, purine, phenylalanine, tyrosine [24]