At-line coupling of UPLC to chip-electrospray-FTICR-MS
At-line coupling of UPLC to chip-electrospray-FTICR-MS
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DOI：
10.1007/s00216-007-1524-4
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发表时间：
2007-11-01
影响因子：
4.3
通讯作者：
Schmitt-Kopplin, Philippe
中科院分区：
文献类型：
--
作者：
Li, Xiaojing;Fekete, Agnes;Schmitt-Kopplin, Philippe
由于扫描速率不同，UPLC与FTICR-MS的高灵敏度在线耦合在技术上是不可行的，因此开发了这些技术的在线耦合以进行快速分析。为了将色谱的一个峰切割成一个部分，研究了几种条件和关系，如插入延迟环的最佳体积，等速下保留时间、环路出口滴速、单个滴体积与流动相组成的关系，以及线性溶剂强度梯度洗脱模式。在FTICR-MS测定前，将UPLC作为高效分离和快速分离工具，获得了良好的重复性结果。采用了一种基于芯片的纳米电喷雾电离系统，该系统非常适合处理小体积组分，因此被选择用于在线耦合。该方法最初应用于无细胞细菌培养上清的加标提取物，其中检测到细菌信号化合物，即n -酰基高丝氨酸内酯（AHL）。重现性好，回收率高。随后，研究了假定产生AHL的Erwinia sp. JX3.2的培养上清，并确定n -己醇-高丝氨酸内酯可能是一个信号分子。与离线测量相比，使用UPLC和FTICR-MS的在线耦合可以实现更可靠的分配。
Since highly sensitive on-line coupling of UPLC with FTICR-MS is technically infeasible due to their different scan rates, at-line coupling of these techniques was developed for rapid analysis. To enable cutting of one peak of the chromatogram into one fraction, several conditions and relationships were investigated, e.g. the optimum volume of the inserted delay loop, the relationship between retention time, loop outlet drop speed, individual drop volume versus mobile phase composition under constant speed, and linear solvent strength gradient elution modes. Good and reproducible results were achieved applying UPLC as an efficient separation and fast fractionation tool before the FTICR-MS measurements. A chip-based nanoelectrospray ionization system was employed which was perfectly suited to handling the small-volume fractions and was thus chosen for the at-line coupling. The method was initially applied to spiked extracts of cell-free bacterial culture supernatants in which bacterial signalling compounds, namely N-acyl homoserine lactones (AHL), were detected. Good reproducibility and high recovery was observed. Afterwards, a culture supernatant of Erwinia sp. JX3.2, a putative AHL producer, was investigated and N-hexanoyl-homoserine lactone was determined as a possible signalling molecule. More reliable assignments were achieved by use of at-line coupling of UPLC and FTICR-MS compared with off-line measurements.