MS-2 fibrosarcoma characterization by laser induced autofluorescence

Background and Objective: MS-2 fibrosarcoma implanted in BALB-CDF1 mice was investigated by frequency and time domain measurements of the autofluoresc ence (AF) radiation emitted upon excitation by a N-2 laser beam (337.1 nm). Study Design/Materials and Methods: AF spectra were obtained by using a spe ctrograph, a multichannel plate and an optical multichannel analyzer for th e steady state detection. Time-resolved spectra were performed by means of a monochromator, a photomultiplier, and a digital signal analyzer. Results: Spectral measurements show that the autofluorescence intensity of pathologic tissue is lower than that of healthy one in the 400- to 500- spe ctral region. In the same spectral range, we found the fluorescence decay t o be the sum of a fast and a slow component. The lifetime of the fast compo nent of tumoral tissue is significantly lower than that of healthy samples. Conclusion: Frequency and time domain measurements used in combination show that MS2-fibrosarcoma is characterized by the probable presence of the fre e form of NADH. (C) 2000 Wiley-Liss, Inc.