2022, Vol. 26 ›› Issue (34): 5475-5481

Preparation and in vitro release of manganese-based metal-organic framework materials loaded with baicalin

Lin Lingqi1, Chen Jin1, Qian Kun2, Zhao Liang1, Shi Yijie1   

Abstract: BACKGROUND:   In recent years, metal-organic framework materials have been widely used in the field of drug carriers. The core metal ions are generally dominated by iron, cobalt, copper, and zinc ions, but there is still a big gap in the study of metal organic frameworks based on the equally important manganese ions.
OBJECTIVE: To synthesize a manganese-based metal organic framework as a drug carrier to load the anti-tumor drug baicalin, and to study its in vitro release behavior.
METHODS: The manganese-based metal organic framework [Mn3(μ3-ade)2(OA)2] synthesized by a hydrothermal stirring method was worked as a drug carrier and loaded the anti-tumor drug baicalin. Before and after loading the drug, the structure, morphology and particle size of the samples were analyzed by X-ray powder diffraction, infrared spectroscopy, scanning electron microscope, and X-ray photoelectron spectroscopy, and the drug-loading and drug release performance of manganese-based metal organic frameworks were investigated.
RESULTS AND CONCLUSION: (1) When the crystallization time was 15 hours, the diffraction peak position, crystallinity and diffraction peak intensity of the synthesized sample were the best. Manganese-based metal organic framework was stable at pH=5.8. (2) After loading the drug, the crystal structure of the manganese-based metal organic framework changed significantly, confirming the successful loading of the drug. Under the conditions that the mass ratio of carrier to drug was 1:1 and the loading time was 8 hours, the drug loading rate was the largest, which could be up to (43.12±1.93)%. (3) The in vitro release test results showed that the cumulative release rate of [Mn3(μ3-ade)2(OA)2] in a release medium whose pH was 5.8 simulated the tumor microenvironment was (71.84±5.96)%. The cumulative release rate in a release medium whose pH was 7.4 simulated the human microenvironment was (48.90±7.21)%. (4) The results show that during the drug loading, the crystal structure and morphology are transformed to achieve the successful loading of baicalin, and the drug release can be controlled according to the pH response, thereby forming an effective drug delivery system.
Key words: baicalin, metal organic framework, antitumor drugs, drug loading rate, sustained drug release, hydrothermal stirring method, drug delivery, pH-responsive release