Development and in vitro evaluation of slippery nanoparticles for enhanced diffusion through native mucus.

Aim: The aim of this study was to investigate the mucus-penetrating properties of neutral nanoparticles comprising poly(acrylic acid) (PAA) and poly(allylamine) (PAM).

Materials & Methods: PAA and PAM nanoparticles were prepared on the basis of ionic interactions between the two polymers. Nanoparticles were characterized by particle size as well as surface charge. The cytotoxicity was examined via resazurin and lactate dehydrogenase assays. Using a modified Ussing chamber with mucus, the diffusion properties of obtained neutral nanoparticles were compared with control particles.

Results: The obtained PAA-PAM nanoparticles demonstrated no significant cytotoxicity and displayed smooth and spherical surfaces, a particle size range of 200 nm and ζ-potential of 0.9 mV. The diffusion efficiency of neutral nanoparticles was 2.5- and 1.8-fold higher than PAM and PAA nanoparticles, respectively.

Conclusion: Taking enhanced mucus-penetrating properties into account, neutral nanoparticles were shown to be very promising in drug delivery via mucus membranes of different cavities.