The Effect of Particle Size on the Absorption of Cyclosporin A Nanosuspension Through the Gastrointestinal Barrier

Background: The particle size is one of great important properties of nanoparticles which affects the dissolution rate in vitro and pharmacokinetics in vivo. This study aimed to design an oral cyclosporin A nanosuspension (CsA-NS) and investigate the effect of particle size of cyclosporin A nanosuspension (CsA-NS) on absorption through the gastrointestinal barrier.Results: CsA-NSs with different particle sizes were prepared. Dissolution rate in vitro, transmembrane permeation, gastrointestinal transport properties and the oral absorption of CsA-NSs were promoted by reducing size, except cellular uptake. Specially the particle size of CsA-NSs was nanoscale, their bioavailability was bioequivalent with marked soft capsules (Sandimmun Neoral®) which is self-microemulsion. Conclusions: This study proposed the potential of developing CsA oral multi dosage form, taken the advantage of nanosuspensions.