Development of ginkgolide B nanocrystals via miniaturized wet bead milling: A QbD approach

Background: Ginkgolide B (GB), a potent platelet-activating factor antagonist with multi-faceted pharmacological effects, suffers from extremely low oral bioavailability due to poor aqueous solubility and permeability. While nanocarriers have been explored, nanocrystal technology offers a carrier-free strategy with ultrahigh drug loading. Objectives: This study aimed to develop an orally administrable GB nanocrystal (GB-NC) formulation using a Quality by Design (QbD) approach to enhance dissolution rate and absorption potential, while ensuring stability and scalability. Methods: GB-NC were fabricated via a miniaturized wet bead milling technique. Critical process parameters were optimized using a Box-Behnken design, with particle size, polydispersity index (PDI), and stability index as key quality attributes. Stabilizers were screened, and lyoprotectants were selected for freeze-drying. The optimized nanocrystals were characterized for morphology, crystallinity, in vitro dissolution, stability, and cellular permeability using MDCK cell monolayers. Results: The optimal formulation, stabilized with PVP K30 (0.51%) and soy lecithin (0.34%) and milled for 10 hours, yielded nanocrystals with a particle size of 82.4 ± 1.97 nm, a low PDI, and good stability. Freeze-drying with glycine/glucose preserved redispersion properties. The GB-NC demonstrated significantly enhanced dissolution (>90% within 20 min) in both simulated gastric and intestinal fluids compared to raw GB. Cellular permeability (Papp) increased significantly, and the freeze-dried product remained stable for 6 months at 4°C and 25°C. Conclusion: A QbD-guided miniaturized wet bead milling process successfully produced stable GB-NC with markedly improved dissolution and cellular permeability. This presents a promising and scalable strategy to overcome the delivery challenges of GB, laying a foundation for developing effective oral formulations to enhance its bioavailability.