MIL-101 (Cr) metal–organic frameworks for systemic delivery of rifampicin antibiotic to lungs

Respiratory pulmonary infections are a serious threat to human health. Their therapy is primarily based on the use of antibiotics. However, non-specific accumulation and low concentration in the target tissue reduce therapeutic effectiveness, cause side effects, and promote the development of antibiotic resistance. In this study, metal-organic frameworks (MOFs) with MIL-101 (Cr) structure were used for delivery of rifampicin to the lungs. The nanoparticles (NPs) showed high antibiotic loading by mass, namely (127 ± 8)% for MIL-101 (Cr) and (82 ± 7)% for amino-modified NH₂-MIL-101 (Cr). The kinetics of drug release had rapid and prolonged phases with up to 40% of the loaded drug released in 7 h. It induces a significant inhibition of bacterial viability at a concentration of NPs as low as 1 mg l^-1. After intravenous administration, the particles showed high tropism for lung accumulation reaching concentration of almost 300%/g of tissue, more than 10 times higher than concentrations in other tissues. This study demonstrates the effectiveness of using MIL-101 (Cr) MOFs for pulmonary drug delivery and holds significant promise for developing antibacterial therapies.