HPLC Six-Valve Injector Usage and Maintenance
High-performance liquid chromatography (HPLC) is a powerful technique used for the analysis of small molecules. HPLC utilizes a column, a mobile phase, a detector and a six-valve injector for analyte separation, collection and analysis. The six-valve injector is the most frequently used injector type in HPLC, due to its wide range of flexibility, simplicity and reproducibility. This article outlines the basics of HPLC six-valve injector usage and preventive maintenance, including installation, use and troubleshooting.
Installation
A six-valve injector should be correctly mounted to the HPLC system in order to ensure optimal performance of the system. The correct installation procedure will depend upon the manufacturer, although it is generally accepted that the injector should be firmly secured to the injector port, both for safety and to reduce adverse effects from any vibration inside the spacer. In addition, tubing from the injector to the HPLC should be properly connected and, if needed, supplied with the appropriate solvent pumps. Finally, the injector should be functionally and accurately calibrated according to the manufacturer’s instructions.
Usage
When using a six-valve injector, a few safety measures must be taken. First, the user must ensure that the injector is filled with the appropriate solvent before use. Second, all solvents must be kept clean, without any contamination. Third, the injector must be carefully operated, as improper use may damage it. Finally, the user must follow the manufacturer’s instructions regarding the amount of sample loaded into the injector.
A six-valve injector enables the user to collect and analyze samples in the most efficient manner. Generally, the injector is loaded with sample outside of the analytical station and then connected to the HPLC system’s column. The advantage in using a six-valve injector is that it allows the researcher to modify parameters such as carrier pressure, injection flow rate, split-split/blow-down volume and stop-valve timing. Thus, the researcher can adjust the HPLC parameters in real-time to ensure optimal chromatographic performance.
Preventive Maintenance
Although a six-valve injector is designed to be robust and reliable, it can be subject to contamination if not adequately maintained. It is important to inspect the injector for signs of contamination and wear, such as dead bands and carryover. The injector should also be cleaned on a regular basis, preferably after each experimental run, to remove any particle deposits that may have accumulated. In addition, the injector should be checked for mechanical problems, such as broken seals or damaged components. If any problems are identified, they should be addressed immediately.
Conclusion
HPLC six-valve injectors are reliable and convenient tools for efficient collection and analysis of small molecules. In order to ensure the injector operates correctly and with maximum efficiency, it is important to follow the manufacturer’s instructions for installation, usage and preventive maintenance. If any contamination or mechanical problems are identified during the operation of the injector, they should be addressed properly in order to maintain optimum performance.
