"Inverse" cloud point extraction coupled with large volume injection ion-pair chromatography: A green route integrating extraction, challenging sample cleanup and on-column concentration into fast simple operation.

The efficient isolation of trace hydrophilic compounds from complicated aqueous-rich samples remains a daunting challenge. Herein, to address the analytical bottleneck, a novel inverse cloud-point extraction (ICPE) strategy was proposed based on the extraction principle opposite to that used in traditional CPE. Then, an original large-volume injection ion-pair chromatography (LVI-IPC) method was developed and systematically investigated based on the retention mechanism of the dynamic ion-exchange model.