Characterization of Nano Bamboo Charcoal Drug Delivery System for Eucommia ulmoides Extract and Its Anticancer Effect In vitro

BACKGROUND Nano bamboo charcoal is being widely used as sustained release carrier for chemicals for its high specific surface area, sound biocompatibility, and nontoxicity; however, there have been no reports on nano bamboo charcoal as sustained release carrier for traditional Chinese medicine (TCM). OBJECTIVE To study the effect of nano bamboo charcoal in absorbing and sustained releasing Eucommia ulmoides extract (EUE) and to verify the in vitro anticancer effect of the sustained release liquid, so as to provide a theoretical basis for the development and utilization of nano bamboo charcoal as TCM sustained-release preparation. MATERIALS AND METHODS The adsorption capacity for the nano bamboo charcoal on EUE was measured by Langmuir model, and the release experiment was carried out under intestinal fluid condition. Characteristic changes for the nano bamboo charcoal nano-drug delivery system with and without adsorption of E. ulmoides were evaluated by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and specific surface area. In addition, the anticancer effect from this novel bamboo charcoal E. ulmoides delivery system was evaluated against a human colon cancer cell line (HCT116). RESULTS It was found that nano bamboo charcoal exhibits good adsorption capacity (up to 462.96 mg/g at 37°C). The cumulative release rate for EUE from this nano bamboo charcoal delivery system was 70.67%, and specific surface area for the nano bamboo charcoal decreased from 820.32 m2/g to 443.80 m2/g after EUE was loaded. An in vitro anticancer study showed that the inhibition rate for E. ulmoides against HCT116 cancer cells was 23.07%, for this novel bamboo charcoal nano-drug delivery system. CONCLUSION This study provides a novel strategy for the delivery of traditional Chinese medicine using bamboo charcoal nano-drug delivery system. SUMMARY The adsorption equilibrium was reached after 30 min of ultrasonic treatmentThe saturated adsorption capacity of Eucommia ulmoides extract by nano bamboo charcoal under ultrosonic condition was 462. 96 mg/gThe cumulative release rate of E. ulmoides extract from the nano bamboo charcoal delivery system in artificial intestinal juice was 70.67%The inhibition ratio of HCT116 cancer cells by sustained release liquid was 23.07%. Abbreviation used: EUE: Eucommia ulmoides extract.