The Raman spectra offluoroorganic compounds show specific emission bands for carbon-fluorine bonds in the range 500-800 wave numbers (car'). With very limited exceptions, biological materials do not contain carbon-fluorine bonds. Fluoroorganic compounds introduced into biological samples can be detected by a Raman emission signal.Normal mode C-F bond bands are observed: (1) at 710-785 cm for trifluoromethyl groups;(2) at 530-610 cm' fbr aromatic organofluorine bonds; (3) a range centered at 690 cm1 for difluoromethylene groups. Specific examples of normal mode C-F bond emissions for organofluorine compounds containing trifluoromethyl groups are: 1-bromopertluorooctane, 726 cm' ; perfiuorodecanoic acid, 730 cm' ; triperfiuoropropylamine, 750 cm' ; 1,3,5-ths-(trifiuoromethyl)-benzene, 730 cm; Fluoxetine (Prozac) commercial powdered pill at 782 cm1 . Compounds containing aromatic C-F bonds are: hexafiuorobenzene, 569 cm' ; pentafluoropyridine, 589 cm . Difluoromethylene groups: perfiuorodecalin, 692 car1; perfiuorocyclohexane, 691 car1Raman spectra were observed with a standard single monocbromator. The 510.8 nm light source was a copper-vapor laser operated at 3-10 watts with 10-12 nanosecond pulses at 10 kHz repetition rate. Detection was made with a time-gated photomultiplier tube. Resonance Raman spectra were also observed at 255.4 nm using a frequency doubling crystal. Observed spectra were free offluorescence with very sharp strong C-F lines.