Identification of Trypsin Digested Transferrin using HPLC and MALDI-MS

Sammanfattning: In this project, separation of trypsin digested transferrin (Tf) has been studied, using a RP HPLC- UV system equipped with a C18 column. 0.1% TFA/MQ-water and 90% MeOH were used as mobile phase A and mobile phase B, respectively. For economic reasons, the protein cytochrome c (cyt-C) was used to optimize the digestion procedure and LC system, before analysis of Tf. Four digestion methods were applied for analyzing cyt-C and Tf. The first method was digestion with no denaturing, reducing or alkylating agent. The other digestion methods used urea or heating as a denaturing agent, and lastly dithiothreitol (DTT) and iodoacetamide (IAA) as reducing and alkylating agent, respectively. The results from HPLC-UV showed that a gradient elution with a high concentration of organic solvent is favorable for the separation of cyt-C peptides. MALDI-MS was used to identify peptides, and the outcomes showed that denaturation by heat before digestion gave the best results.