Automated HPLC Separation Using LC-mate: An Integrated Repetitive Autosampler and Fraction Collector for Microscale Purification

High-performance liquid chromatography (HPLC) plays a crucial role in the purification of high-value compounds, meeting the increasing demands of chemistry and biology disciplines in both academic and industrial settings. However, repeated manual injection and fraction collection during microscale purification significantly limit efficiency and reproducibility. To overcome this bottleneck, we have developed an integrated autosampler and fraction collector system, temporarily named LC-mate, which automates repetitive separations by responding directly to analog signals from the HPLC detector. The instrument is constructed around a high-pressure six-port switching valve for sample injection and a selector valve for fraction collection, with operational parameters controlled via an intuitive touchscreen interface. LC-mate is compatible with commercial HPLC detectors capable of analog output and can also achieve repetitive separation of gradient elution mode through synchronous signal triggering. Demonstration experiments confirmed stable operation and reproducible separations for natural product purification, showing a clear reduction in manual handling time. The system offers a practical and accessible solution for enhancing automation in conventional HPLC workflows, bridging the gap between manual and fully automated purification systems.