Study Of High Performance Liquid Chromatography Combining With Electrospray Ion Mobility Spectrometer

Ion mobility spectrometry(IMS)has been recognized as a sensitive and rapid gas phase separation technique,and has already been applied to public security,food safety,biomedicine,environmental monitoring and battle field detection due to its rapid detection and high sensitive.Based on the study of electrospray ionization-ion mobility spectrometer,the high performance liquid chromatography-electrospray array ionization-ion mobility spectrometer(Arrayed ESI-IMS)was developed,which provides a fast and high-resolution method for the separation of complex systems such as natural product extracts.The main results and conclusions are as following:1.In order to improve electrospray ionization efficiency,a circular electrospray emitter array ion source was fabricated with quartz capillary etched with hydrofluoric acid.,and the developed arrayed electrospray ionization source was applied to the ion mobility spectrometer and interfacing to high performance liquid chromatography.Various parameters affect Arrayed ESI-SA IMS signal to noise ratio were investigated and optimized,and the results showed the optimun conditions were: the drift tube temperature 140℃,electrospray voltage 4.5 kv,sample flow rate 8 μL/min,methnol concentration is 90%.The linear range,limit of detection,precision and reproducibility of ESI IMS were evaluated by using a traditional single electrospray ionization and an arrayedelectrospray ionization with six kinds of tetraalkylammonium bromide compounds.The merits of method were as following: linear range of single electrospray ionization and arrayed electrospray ionization with six tetraalkylammonium bromide compounds were 0.625~50 nmol/m L and 0.312~25 nmol/m L,limit of detection 0.35~1.05 nmol/m L,0.25~0.75 nmol /m L respectively.The resolution of arrayed electrospray ionization is slightly lower than the single electrospray ionization.2.High performance liquid chromatography were hyphenated to ion mobility specgrometer using developed arrayed electrospray ionization source and applied to simultaneous determination of six kinds of tetraalkylammonium bromide compounds and anthocyanins of grape skin,the results demostrate that the ability to analyze complex samples with HPLC-IMS method is superior than HPLC alone.By using hyphenated methods,the limit of detection(S/N=3)of analysis six kinds of tetraalkylammonium bromide compounds are 4.43,2.95,3.32,4.83,5.90 and 10.62 nmol/m L,respectively.At least 35 anthocyanins from the Muscat prape,16 anthocyanins from Summer Black,15 anthocyanins from Black currant and 12 anthocyanins from Crimson Summer were differentiated using developed HPLC-Arrayed ESI-IMS method.3.In order to further improve the sensitivity of hyphenated HPLC-IMS method,the performance of Fourier Transform ion mobility spectrometry was evaluated.Real-time data acquisition and processing of frequency modulation Fourier transform IMS were acheived with a traditional single ion gate ion mobility spectroscopy using Labview programming,various parameters that affect FT IMS singal to noise ratio were optimized,the results showed the best conditions were: the sampling rate 50000 Hz/s,Sweeping rate 2500 Hz/s,sampling time 8 s,Window function is Wetch function,drift tube temperature is 140℃,electrospray voltage 4.5 kv,solvent flow rate 8 μL/min,methol content is 90%.The linear range,detection limit,precision and reproducibility of Arrayed ESI-FT IMS were studied by using a single electrospray ionization and Arrayed electrospray array ionization with six kinds of tetraalkylammonium bromide compounds.The linear range of single electrospray ionization and Arrayed electrospray array ionization with six tetraalkylammonium bromides were 0.312~50 nmol/m L,limit of detection 0.12~ 0.38 nmol/m L,0.156~25 nmol/m L,0.07~0.23 nmol/m L respectively.The resolution of arrayed electrospray ionization is slightly lower than the single electrospray ionization.Further more,FT-IMS was coupled to HPLC for the determining of six tetraalkylammonium bromide,the results show that the ability to analysis complex samples with HPLC-Arrayed ESI-SA IMS method is superior to use HPLC alone,with the limit of detection(S/N=3)2.58,2.66,2.52,3.42,5.38 and 8.72 nmol/m L,respectively.4.The frequency modulation Chirp-Z transform ion mobility spectrometers was developed for the first time.The performance including signal-to-noise ratio and resolution of Chirp-Z transform IMS were compared to the FT transform method with six tetraalkylammonium bromides,the results show that there is no significant difference between the signal-to-noise ratio,and the resolution of the Chirp Z transform method is better than FT.Most important of all,the drift time measurement resolution is much higher than traditional FT IMS.Chirp-Z ims was also coupled to HPLC with arrayed ESI to separate six tetraalkylammonium bromides,and investigate the linear range,detection limit,precision and reproducibility.The results show that: the method limit of detection(S/N)of six tetraalkylammonium bromide compounds are 2.46,2.03,2.09,3.28,5.17,7.00 nmol/m L respectively.