Felodipine nanosuspension: a faster in vitro dissolution rate and higher oral absorption efficiency

In the present work, nanocrystals were prepared to improve oral bioavailability of felodipine. Several important formulation factors and process parameters were explored, optimized and analyzed systematically. The prepared nanocrystals were characterized for morphology, particle size, zeta potential, possible crystallization changes, release behavior and oral absorption. The morphology of the obtained nanocrystals was found to be rod shape. The particle size and zeta potential were 140 ± 10 nm and -29.11 mV, respectively. The X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis indicated that felodipine had undergone crystal form transition. The dissolution rate of felodipine was significantly increased and the AUC0 -t value of felodipine colloidal dispersion in beagle dogs was approximately 1.6-fold greater than that of the commercial tablets. Nanocrystals impose a faster dissolution rate and higher oral absorption efficiency than raw crystals, and show great potential as an effective strategy for improving oral bioavailability of poorly soluble drugs.