Cao P, Moini M
Department of Chemistry and Biochemistry, The University of Texas at Austin, 78712, USA.
Electrophoresis. 1998 Sep;19(12):2200-6. doi: 10.1002/elps.1150191226.
Pressure assisting and pressure programming the inlet of the capillary electrophoresis instrument were used for the analysis of peptide mixtures and protein digests using capillary electrophoresis/electrospray ionization-mass spectrometry (CE/ESI-MS). CE/ESI-MS of peptide mixtures and tryptic digests of proteins was studied using three different types of capillary columns: (i) a freshly aminopropylsilane (APS)-treated column, (ii) an untreated column, and (iii) a degraded APS-treated column. To maintain a constant and adequate buffer flow toward the CE capillary outlet for stable CE and ESI operation, low pressure was applied to the inlet of the CE when an untreated or degraded APS capillary was used. By programming the inlet pressure, CE/ESI-MS analysis time was reduced to 1/3 of its original time. The utility of this technique is demonstrated by CE/ESI-MS analysis of a hemoglobin variant (hemoglobin-S) and its tryptic digests. Identification of the mutant peptide in the tryptic digest of hemoglobin-S was achieved by collision-induced dissociation (CID) of the protein digests using CE/ESI time of flight-mass spectrometry (TOF-MS).
采用毛细管电泳仪入口压力辅助和压力编程，结合毛细管电泳/电喷雾电离质谱（CE/ESI-MS）对肽混合物和蛋白质酶解产物进行分析。使用三种不同类型的毛细管柱研究了肽混合物和蛋白质胰蛋白酶酶解产物的CE/ESI-MS：（i）新的氨丙基硅烷（APS）处理柱，（ii）未处理柱，以及（iii）降解的APS处理柱。当使用未处理或降解的APS毛细管时，为了向CE毛细管出口维持恒定且充足的缓冲液流动以实现稳定的CE和ESI操作，在CE入口施加了低压。通过对入口压力进行编程，CE/ESI-MS分析时间缩短至原来的1/3。通过对血红蛋白变体（血红蛋白-S）及其胰蛋白酶酶解产物进行CE/ESI-MS分析，证明了该技术的实用性。使用CE/ESI飞行时间质谱（TOF-MS）通过蛋白质酶解产物的碰撞诱导解离（CID）实现了血红蛋白-S胰蛋白酶酶解产物中突变肽的鉴定。
