Table 4.

Overview of endogenous fluorophores from literature potentially contributing to observed EEM peaks

Observed ex./em. wl. (nm)	Endogenous fluorophores (ex./em. wl. in nm)	Name assigned
280–300/283.5–383.5	Elastin (285/350 [15]) (290/365 [16])	Peak A
	Tryptophan (295/340–350 [24]) (295, 280/345, 350 [13]) (260–295/325–375 [18])
	Tyrosine (280/312 [13]) (270/320 [44]) (275/300 [12])
320–340/335–435	Collagen (340/390 [11]) (345/395 [12]) (337/380–420 [13])	Peak B
	Pyridoxine (332, 340/400 [13]) (310/400 [11]) (310/400 [12])
355–375/420–520	Kynurenine (380/480 [33]) (365/480 [34]) (360/460–470 [35])	Peak C
	NADH (350/460 13]) (355/475 [11]) (350/470 [12])
	Protein carbonyls (360/385 [41]) (350/435 [42]) (350/450 [43]) (350/400–500 [23])
430–450/407–507	Flavins (455/495 [15]) (460/550 [11]) (440–450/540 [14]) (440–450/500–550 [32])	Peak D
450–470/633–733	Unknown	Peak E

ex.: excitation; em.: emission; wl.: wavelength