CryoStore combines biology and engineering
The CryoStore project is not just about biology! Two of our Doctoral Candidates are working at The Institute for Multiphase Processes, Leibniz University Hannover, combining biology and engineering to improve cryopreservation techniques.
Photo 1: Prototypes of custom diffusion chambers.
Oleksandra Hubenia
Non-invasive visualisation of changes in reproductive cells during cryopreservation
My project combines engineering and biology to improve cryopreservation techniques. We are developing a Raman microscopy system with a temperature-controlled diffusion chamber to non-invasively track how cryoprotective agents (CPAs) enter reproductive cells.
Right now, we’re in the final stages of building a custom diffusion chamber that will fit into the microscope (photo 1). At this stage, I am analyzing volumetric responses of porcine oocytes to cryoprotectant exposure using cryomicroscopy (photo 2 and 3). In the next phase, these observations will be validated through RAMAN spectroscopy with our new diffusion chamber to establish a correlation with the underlying molecular diffusion processes. This integrated approach will help us better understand CPA diffusion and reduce cell damage during freezing.
Picture 2: Oleksandra Hubenia and the cryomicroscope.
Photo 3: Analyzing volumetric responses of porcine oocytes to cryoprotectant exposure using cryomicroscopy.
Abdul-Rashid Iddi
Development of a directional freezing cryostage for cell imaging using multiphoton microscopy
My project focuses on designing a directional freezing cryostage that enables thermal control for studying ram sperm cells during cryopreservation. Unlike conventional setups, this cryostage integrates liquid nitrogen cooling, PID-regulated heating wires, and compatibility with multiphoton microscopy—allowing real-time visualization of cellular dynamics during freezing. Currently, I’m collaborating with LLS Rowiak to optimize imaging parameters and fluorescent dyes, ensuring high-contrast visualization of sperm obtained from the Clinic for small cloven-hoofed animals and forensic medicine and outpatient clinic, University of Veterinary Medicine Hannover. My next steps is to collaborate with a mechanical engineer to design and develop the cryostage for validation.
The multiphoton microscope.
Abdul-Rashid studying real-time visualization of cellular dynamics during freezing.
I recently presented at the 49th Annual Conference of Young Scientists - "Cold in Biology and Medicine - 2025”. My presentation explored my preliminary findings on using confocal imaging to assess sperm cell viability after cryopreservation. Methods included staining protocol using Calcein AM (for live cell viability) and Propidium Iodide (membrane integrity assessment). The preliminary findings suggest a reduction in percentage viability which could be attributed to both the freezing process as well as the lack a heating stage for the microscope.
