Development Of A Ionic Liquids/mesoporous Materials Capillary Electrochromatoography Column For Separating Micro-particles

In recent years,the preparation and characterization ability of micro-objects in medicine,biology,chemistry,energy and other fields are the key factors influencing the rapid development of these areas.As the application of micro-objects size more and more widely,in order to obtain accurate analysis results,the separation is essential and necessary.As for micro-objects,its separation technology is not yet mature,and less commercialized instruments.Therefore,it is very necessary of the develope a wide scope of application,simple device,easy separation instrument.Based on the mentioned above,our lab established a novel,self-assembly,lateral electric field capillary chromatographic technique for the micro-objects separation which is on the basis of the electrophoresis and the chromatographic technique.The proposed lateral electric field capillary chromatography is comprised of a stainless steel tube and a platinum wire as the external electrode and internal electrode of separation column.apply pulse voltage on the two electrodes,the separation channel transverse electric field is generated,when the target into the separation column,will be affected by the coulomb force,viscous drag and adsorbability of chromatographic column surface produced.It can be separeted according to the target retention time difference which caused the differences of the size and charge of the target in the chromatographic column.Through preliminary experiments show that the technology for the separation of particles is a role,but there is the problem of low degree of separation,the main reason is can't apply larger voltage due to contact between the electrode and the mobile phase,so lead to less theoretical plate number.And by modifying the tetraethyl orthosilicate as the mesoporous materials on the surface between the interal stainless steel tube and the platinum wire.And joining methyltri-n-octylammonnium bis(trifluoromethanesulfonyl)imde ionic liquids into the hole of mesoporous material to increase working voltage so that increasing the opportunity of the particals contacting with the electrode surface.Increase the theoretical plate number and retention time,and thus enhanced the degree of separation of micro-objects.The choice of ionic liquids is affects the size of the voltage,the voltage and frequency are the important factors influencing the degree of separation,What's more,when applying the lateral electric field on the system after modifying ionic liquid,we can find that the working voltage can reach 5 V and the frequency 4 Hz for the 6 mixed particles achieve a good resolution better than without modified these material.The result shows that this technology can realize the on-line and efficiently separate the micro-objects,achieving a good separating degree,and no damage to the sample.Most importantly,these system provides a good prospect for the separation of microscales such as cell separation material and make a better reference.