Acquisition of collapse temperature and the influencing factors during freeze-drying of placental decellularized matrix in freeze-drying microscopy based on image processing techniques

Abstract

The placenta-derived extracellular matrix is an ideal material for making freeze-dried sponges as a wound dressing. In order to prepare a porous sponge, collapse temperature is one of the most important parameters in process of freeze-drying. This work used an image processing method to determine the collapse temperature of extracellular matrix slurry during freeze-drying. By using this technology, the variation of collapse temperature under different cooling rates, heating rates, annealing conditions are studied, and the influence of ice crystal size on collapse temperature is further analyzed. In addition, an annealing operation is used to control the size of ice crystals inside the sample. The actual results are consistent with the fact that annealing increases the ice crystal size and collapse temperature. The image processing algorithm can greatly improve the accuracy of obtaining the collapse temperature to shorten the period of exploration of the key freeze-drying parameters of solid-liquid mixtures.

Keywords:

• Collapse temperature
• placenta-derived extracellular matrix
• freeze-drying microscopy
• image processing

Disclosure statement

The authors declare no competing financial interest.

Additional information

Funding

This work was partially supported by a grant from National Natural Science Foundation of China (No.52076140).