The potential for production of freeze-dried oral vaccines using alginate hydrogel microspheres as protein carriers

作者：Hariyadi D M^*; Ma Y; Wang Y; Bostrom T; Malouf J; Turner M S; Bhandari B; Coombes A G A

来源：JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY, 2014, 24(2): 178-184.

DOI：10.1016/S1773-2247(14)50029-9

• Oral vaccine
• Alginate hydrogel microspheres
• Maltodextrin cryoprotectant
• Protein
• Bovine serum albumin
• ESEM
• In vitro release

Oral administration of dry vaccine formulations is acknowledged to offer major clinical and logistical benefits by eliminating the cold chain required for liquid preparations. A model antigen, bovine serum albumin (BSA) was encapsulated in alginate microspheres using aerosolisation. Hydrated microspheres 25 to 65 mu m in size with protein loading of 3 3 % w/w were obtained. Environmental scanning electron microscopy indicated a stabilizing effect of encapsulated protein on alginate hydrogels revealed by an increase in dehydration resistance. Freeze drying of alginate microspheres without use of a cryoprotectant resulted in fragmentation and subsequent rapid loss of the majority of the protein load in simulated intestinal fluid in 2 h whereas intact microspheres were observed following freeze-drying of BSA-loaded microspheres in the presence of maltodextrin. BSA release from freeze-dried preparations was limited to less than 7 % in simulated gastric fluid over 2 h. while 90 % of the protein load was gradually released in simulated intestinal fluid over 10 h. SDS-PAGE analysis indicated that released BSA largely preserved its molecular weight. These findings demonstrate the potential for manufacturing freeze-dried oral vaccines using alginate microspheres.

• 出版日期2014