Influence of pH, temperature, and alternating magnetic field on drug release from Keggin-type heteropoly acid encapsulated in iron-carboxylate nanoscale metal-organic framework

摘要

Nanosized mesoporous iron-carboxylate [MIL-100(Fe)]-encapsulated Keggin phosphotungstic acid H3PW12O40 (PW) was fabricated via an environmentally friendly hydrothermal synthesis method and characterized by Fourier-transform infrared spectroscopy, high-resolution transmission electron microscopy, field-emission scanning electron microscopy, particle size analysis, and powder X-ray diffraction analysis. The metal content was analyzed by energy-dispersive X-ray spectroscopy. PW@ MIL-100(Fe) was then studied as a drug delivery system, exhibiting the ability to entrap epirubicin (EPI) as a model drug. The drug loading efficiency, drug content, and drug release behavior of PW@ MIL-100(Fe), MIL-100( Fe), and PW@ HKUST-1 [where HKUST-1 is Cu-3(BTC)(2) with BTC = benzene-1,3,5-tricarboxylic acid] were also studied. The results indicate that PW@ MIL-100(Fe) possessed high adsorption capacity (28 wt%) and loading efficiency (91.6 %) for epirubicin. Drug release from PW@ MIL-100(Fe) at different pH values (5, 5.8, 6.5, and 7.4) and temperatures and with an alternative magnetic field was investigated, and the stability of the nanocarrier after EPI release was studied by Fourier-transform infrared spectroscopy and field-emission scanning electron microscopy. Cellular toxicity was also investigated. The results show that this is a good candidate as a future drug nanocarrier.