Current prospects on nano liquid chromatography coupled to electron ionization mass spectrometry (nanoLC-EI-MS)

NanoLC consolidates as powerful analytical technology liable to provide improved chromatographic performance and superior detection capabilities. Significant instrumental advances have been accomplished in the last 20 years to make nanoLC instruments more robust, accurate, and amenable for routine analysis. Similarly, new stationary phases and nanoLC formats provide new opportunities for separations at the miniaturized scale. Besides, nanoLC makes the hyphenation with EI-MS feasible, and a series of interfaces and interesting applications have been reported in the last years. Ei-MS offers unparallel identification capabilities, and its coupling with nanoLC has the potential to revolutionize the Performance of LC-MS untargeted studies. This manuscript makes a historical journey through the development of the nanoLC and its hyphenation with the EI-MS, exploring the more outstanding advances in that technology, discussing its scope, and identifying its limitations. We intend to give the reader a current overview of the state of the art of nanoLC and point out perspectives and future lines of advancement and improvement for new research in this area.