Abstract: We detect the components of black gel ink handwriting with high performance liquid chromatogramtime of flight mass spectrometer. We applied methanol and water (1：1,V/V) compound to the extraction of samples and ESI+ mode to their detection. We also extracted specific ion in every sample by differential proteomics method. We eventually analyzed the results by SPSS software principal component analysis method. Results show that 24 kinds of samples can all be effectively distinguished. This research can provide a new method for the distinction of gel pen type and the identification of writing time moment.

Key words: high performance liquid chromatogramtime of flight mass spectrometer, handwriting identification