Mechanochemical preparation of chrysomycin A self-micelle solid dispersion with improved solubility and enhanced oral...

Chrysomycin A (CA) has been reported as numerous excellent biological activities, such as antineoplastic and antibacterial. Though, poor solubility of CA limited its application in medical field. Due to good amphiphilicity and potential anticancer effect of disodium glycyrrhizin (Na₂GA) as an excipient, an amorphous solid dispersion (Na₂GA/CA-BM) consisting of CA and Na₂GA was prepared in the present study by mechanochemical technology (roll mill ML-007, zirconium balls, 30 rpm, 2.5 h) to improve the solubility and oral bioavailability of CA. Then, Na₂GA/CA-BM was self-assembled to micelles in water. The interaction of CA and Na₂GA in solid state were investigated by X-ray diffraction studies, polarized light microscopy, and scanning electron microscope. Meanwhile, the properties of the sample solution were analyzed by dynamic light scattering and transmission electron. Furthermore, the oral bioavailability and antitumor ability of Na₂GA/CA-BM in vivo were tested, providing a theoretical basis for future application of CA on cancer therapy.

CA encapsulated by Na₂GA was self-assembled to nano-micelles in water. The average diameter of nano-micelle was 131.6 nm, and zeta potential was - 11.7 mV. Three physicochemical detections showed that CA was transformed from crystal into amorphous form after treated with ball milling and the solubility increased by 50 times. Na2GA/CA-BM showed a significant increase of the bioavailability about two time that of free CA. Compared with free CA, the in-vivo antitumor studies also exhibited that Na₂GA/CA-BM had an excellent inhibition of tumor growth.

Na₂GA/CA-BM nanoparticles (131.6 nm, - 11.7 mV) prepared by simple and low-cost mechanochemical technology can improve oral bioavailability and antitumor efficacy of CA in vivo, suggesting a potential formulation for efficient anticancer treatment.