University of Cambridge, Department of Chemical Engineering - R&D Services

University of Cambridge, Department of Chemical Engineering
Within our lab we have a small scale freeze dryer which we can use to dry vials of products. We also have a small drying chamber in which the progress of a drying front can be observed through a microscope. The drying equipment is housed within a fully featured biological facility which permits the analysis of the effect of drying on biologicals.
Freeze Drying Microscopy (FDM)
The freeze drying microscope, which is shown in the larger of the images to the left enables us to determine factors such as the collapse temperature of a product, and the porosity of the cake produced in order to scientifically design freeze drying cycles for use in the lab scale freeze dryer. Watching freeze drying through the microscope is a slow boring process. To relieve the tedium we've rigged it up to a computer and a video to record it so we don't actually have to watch it, though we do sometimes, more...
Freeze Drying in a Laboratory Freeze Dryer
Our lab scale freeze dryer enables us to quickly assess the effect of various cycle parameters and excipients on the products. Again it is computer controlled, and key parameters are logged by the software. more...
Freeze Drying Virus
Devising novel formulations to protect an enveloped virus though the drying process is another of our activities, more...

The density plot to the right shows the variation in sublimation rates in different locations within the lab scale freeze dryer. Each grid square represents a vial, the slowest sublimation, shown by the lighter squares occurs at the bottom of the grid and around the edges. The bottom of the grid corresponds to the location of the freeze dryer door. It is common practice to place vital products in vials towards the centre of the dryer where the sublimation is both faster and more consistent.
University of Cambridge
Department of Chemical Engineering
University of Cambridge,
Cambridge CB2 3RA, UK