Freeze-Drying of Plant Tissue Containing HBV Surface Antigen for the Oral Vaccine against Hepatitis B

Figure 1

Efficiency of freeze-drying represented as preservation of S-HBsAg VLPs (a) and total (b) in lettuce leaves soaked with a series of excipients and processed under two temperature profiles. Preservation effectiveness [%] calculated as the ratio of VLP-formed and total S-HBsAg in powdered lyophilised product to the antigen content in fresh tissue multiplied by weight loss degree. Star indicates the variant selected for further experiments (see text for details).