Flow Cytometry - Flow Cell Care & Maintenance

Flow Cytometry Flow Cell Care and Maintenance

Precision Cells has been manufacturing flow cells for flow cytometry, HPLC, life sciences, etc. for over 50 years.  Being a manufacturer of flow cytometry cells it's important to understand how to properly take care of and maintain flow cells to keep a flow cell operating at maximum capacity.

The improper use and care of a flow cytometry cell can cause inaccurate readings and inaccurate data.  Improper care can also mean having to spend hours on the phone with customer service, having to send your machine in for service, or having to completely replace the flow cell.  In some cases the entire optics system has to be taken out to replace the cell.

Chemicals to stay away from

Today's industry standards are that most flow cells are made from quartz windows or fused silica components, so staying away from alkaline solutions with pH more than 9.5 is critical. These solutions could attack the quartz and impair optical performance.   What happens is that these solutions can etch the quartz making the flow cell almost unusable.  Users will notice "streaks" in the channel of the flow cell and if these streaks appear where the laser or detector is located, the flow cell will cease to function.

How to Avoid Crystallization

Avoiding crystallization is very important.  To avoid crystallization within a flow cell, the user should always flush it with water.  A thorough flushing is necessary after running buffers or salt solutions, especially high pH solutions. Whenever scientists leave a device unused overnight, it is important to make certain the flow cell contains a minimum of 10% organic mobile phase to avoid algae growth.  Special coatings can be applied to the quartz material to help prevent these types of growths.

Cleaning

A clean flow cell and optical connectors/assemblies are crucial for ensuring proper operation of any flow cytometer or any machine that uses flow cells.  An  important note is to not allow solutions to dry up in a flow channel cell.  Solutions that contain dissolved salts, proteins or another solid solutes will damage the flow path. Also researchers must be careful not to allow particles to go in the flow cell as harm to the flow cell, such as scratching, may occur.  Scratches will have a negative effect on the performance of the flow cell and if they are in the detector area, the flow cell will not work.

For easy cleaning, flush a tiny bit of distilled water through the flow cell. Take a syringe and fill it using a 10% surface active detergent solution.  Insert the syringe into the flow cell and spray the detergent into the cell. After a few squirts, leave the solution inside the flow channel for a little over 2 hours.  The flow cell must be rinsed thoroughly using distilled water.

Overnight a flow cell can be left filled with buffer. Weekend and long-term storage PC recommends to flush the flow cell with distilled water after which fill it with 20% ethanol.  For drying purposes the flow cell may be dried using a stream of clean nitrogen.