Drugs are often lyophilised to extend the shelf life, a process which works by freezing the material, then reducing the pressure and adding heat to allow the frozen water in the material to sublimate. Many medical test devices use lyophilised beads as a medium for carrying the reagents.
Manufacturing the frozen beads prior to water removal can be a challenge. We started working on this process in conjunction with a team at Cambridge University in 2004. The challenge has always been to dispense accurate droplets of reagents into a nitrogen bath, keeping the droplet whole and segregated while they freeze.
The original design has undergone improvements since then and we are still making the freezing equipment now. We currently use motorised syringe pumps to dispense the reagent, and have an in-house team evaluating other technologies such as automated pipetting and pressurised reservoir dispensing, as these systems have become more reliable and may provide an alternative solution for reagent dispensing.