Spray-dried microparticles: a potential vehicle for oral delivery of vaccines

This study aims to formulate a microparticle-based system that protects the protein from the harsh gastric conditions and also provides appropriate uptake via M cells for desired immune response upon oral administration. The formulation was derived using a valid statistical model, analysed by JMP® (SAS). The average size and charge of the resulting microparticles were 1.51 ± 0.125 µm and + 15.7 ± 2.5 mV, respectively. Moreover, the particles provided a prolonged release over a period of 8 hrs which ensures M-cell uptake of intact particle with antigen (Kunisawa et al., 2011). This was further supported with in vivo studies where particle uptake was found in Peyer's patches of small intestine when observed for 8 h. Thus, these microparticles can be used as an efficient vaccine delivery vehicle upon oral administration.