Biocompatible nanoemulsions based on hemp oil and less surfactants for oral delivery of baicalein with enhanced bioavailability

Baicalein (BCL) possesses high pharmacological activities but low solubility and stability in the intestinal tract. This study aimed to probe the potential of nanoemulsions (NEs) consisting of hemp oil and less surfactants in ameliorating the oral bioavailability of BCL. BCL-loaded NEs (BCL-NEs) were prepared by high-pressure homogenization technique to reduce the amount of surfactants. BCL-NEs were characterized by particle size, entrapment efficiency (EE), in vitro drug release, and morphology. Bioavailability was studied in Sprague-Dawley rats following oral administration of BCL suspensions, BCL conventional emulsions, and BCL-NEs. The obtained NEs were ~90 nm in particle size with an EE of 99.31%. BCL-NEs significantly enhanced the oral bioavailability of BCL, up to 524.7% and 242.1% relative to the suspensions and conventional emulsions, respectively. BCL-NEs exhibited excellent intestinal permeability and transcellular transport ability. The cytotoxicity of BCL-NEs was documented to be low and acceptable for oral purpose. Our findings suggest that such novel NEs and preparative process provide a promising alternative to current formulation technologies and suitable for oral delivery of drugs with bioavailability issues.