Soft nanoparticles for chrysin delivery: an evidence mapping of nanocarrier strategies and biological applications

Chrysin, a naturally occurring flavonoid found in honey, propolis, and various medicinal plants, exhibits a wide spectrum of promising pharmacological activities, including potent antioxidant, anti-inflammatory, neuroprotective, and anticancer properties. These therapeutic potentials are, however, severely constrained by their inherent physicochemical challenges, primarily their pronounced hydrophobicity, low stability under physiological conditions, and poor oral bioavailability, which limit their clinical translation. To overcome these barriers, nanoencapsulation has emerged as a promising strategy. This scoping review maps the existing scientific literature to synthesize evidence on how encapsulating chrysin within soft nanocarriers, such as lipid, polymeric, and protein-based nanoparticles, influences its bioavailability and therapeutic efficacy. Following PRISMA-ScR guidelines, 74 studies were included from three major databases: PubMed, Scopus, and Web of Science. The findings demonstrate that nanoformulations consistently enhance chrysin's solubility, stability, and pharmacokinetic profile, resulting in significantly greater biological effects in preclinical models across diverse applications, most notably in oncology and neuroprotection. These systems enable targeted delivery, controlled release, and improved biodistribution, such as facilitating blood-brain barrier penetration. Despite compelling preclinical evidence, the review identifies a critical translational gap, with a complete absence of clinical trials and a predominance of in vitro studies. This synthesis consolidates the current knowledge landscape and highlights the transformative potential of nanotechnology for chrysin delivery. Future research is needed to address safety, scalability, and rigorous in vivo validation to translate this promising research into real-world treatments for patients.