Table 1.

Chemical structures of external and internal standards.

Name	Structure	External	Internal
Carbazole	Blue: Nitrogen	O
Anthracene		O	O
4,6-dimethyldibenzothiophene (4,6-DMDBT)	Yellow: Sulfur	O	O
Pyrene		O
benzonaphthothiophene	Yellow: Sulfur	O
Perylene		O	O
coronene		O	O
benzocarbazole	Blue: Nitrogen		O
Dibenzo[g,p]chrysene (DBC)		O	O
Dibenzo[a,l]pentacene (DBP)		O
Polyethylene glycol (PEG)	Red: Oxygen	O	O