- Mass-spectroscopic and vibrational spectroscopic methods were applied for the analysis of human blood samples from healthy subjects and patients in order to detect spectral peaks which might serve as biomarkers for monitoring and iden- tification of specific diseases. In the present study samples of serum were obtained from healthy and patient persons suffer- ing from diarrhea and analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and microscopic Fourier transform infrared spectroscopy (FTIR). The results obtained by both spectroscopic techniques show similar and con- sistent spectral peaks in all the examined sera obtained from healthy persons. In all tested patient samples two unique interesting peaks appeared at m/z 11,553 and 11,710 in MALDI-TOF spectra and a peak at area 1600 cm −1 was significantly reduced in all of the tested patient samples in FTIR spectra. These parameters might be used as a basis for developing a spectral method for the detection and identification of specific human diseases and probably other disorders. It seems that a combination of these two techniques may provide much more reliable results for the detection and identification of various abnormalities.