The application of Raman spectrum and MALDI-TOF MS on gastric cancer and colon cancer diagnosis

Gastrointestinal System cancer is one of the commonly occurring cancers in Asia region. In recent years, its mortality rate is even in the top five in Taiwan. It needs time and precise judgment by doctors, and requires large amount of time, money and human labor, if the sample derived from endoscopic observation or surgery is to be determined if it is cancerous by pathology examination. Raman Spectrum was discovered in 1928, and the scattering light was too weak to be detected effectively. Due to the advancement of laser and the enhancement of light source, the detection was therefore made easier and had been used widely these years. By co-operating with different laser induced light, it can be applied to different substance analysis, and by the scattering light excited by laser, substances can be corresponded to different compound. By comparing the location and intensity of scattering spectrum of normal and cancerous tissue, and the comparison of tissue structures pathologically, the existence of difference between normal and cancerous tissue can be discovered. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has recently become a popular and versatile method to analyze macromolecules from biological origin. The application of MALDI-TOF-MS detect on clinical chemistry and biology. MALDI-TOFMS is used in clinical chemistry, e.g. disease markers can be identified with MALDI-MS analysis.