线形离子阱电子捕获解离装置的设计与实验研究OA

Electron capture dissociation(ECD)is an important dissociation method for characterizing post-translational modifications of biomolecules in protein mass spectrometry,serving as a complement to traditional tandem mass spectrometry.In this study,an ECD device based on digital linear ion trap(DLIT)technology was designed,and an electron emission source equipped with an elongated hot cathode was developed to provide low-energy electrons for ECD reactions.SIMION software was employed to simulate and optimize the electron transmission system,and the simulation results showed that the electron transmission efficiency of the device reached 90.66%.Cathode emission characterization tests were further performed to investigate the relationship between the cathode bias voltage and the electron beam current reaching the ion reaction region,and to determine the operating parameters of the emission source.Finally,in-trap ECD experiments were conducted using the standard peptide Substance P.The results demonstrated that the cathode generated sufficient reaction electrons,and adjusting the bias voltage effectively increased the number of electrons entering the ion trap.Successful experiments produced tandem mass spectra,enabling accurate peptide sequencing,thereby validating the feasibility of the developed device.