The vibrational spectral differences of normal and lung cancer cells were studied for the development of effective cancer cell screening by means of attenuated total reflection infrared spectroscopy. The phosphate monoester symmetric stretching nu(s)(PO3(2-)) band intensity at ~970 cm(-1) and the phosphodiester symmetric stretching nu(s)(PO2(-)) band intensity at approximately 1,085 cm(-1) in nucleic acids and phospholipids appeared to be significantly strengthened in lung cancer cells with respect to the other vibrational bands compared to normal cells. This finding suggests that more extensive phosphorylation occur in cancer cells. These results demonstrate that lung cancer cells may be prescreened using infrared spectroscopy tools.