Tumour microenvironment hinders nanoparticle transport deep into the tissue precluding thorough treatment of solid tumours and metastatic nodes. We introduce an anticancer drug delivery concept termed FlaRE (Flash Release in Endothelium), which represents alternative to the existing approaches based on enhanced permeability and retention effect. This approach relies on enhanced drug-loaded nanocarrier accumulation in vessels of the target tumour or metastasised organ, followed by a rapid release of encapsulated drug within tens of minutes. It leads to a gradient-driven permeation of the drug to the target tissue. This pharmaceutical delivery approach is predicted by theoretical modelling and validated experimentally using rationally designed MIL-101(Fe) metal-organic frameworks. Doxorubicin-loaded MIL-101 nanoparticles get swiftly trapped in the vasculature of the metastasised lungs, disassemble in the blood vessels within 15 minutes and release drug, which rapidly impregnates the organ. A significant improvement of the therapeutic outcome is demonstrated in animal models of early and late-stage B16-F1 melanoma metastases with 11-fold and 4.3-fold decrease of pulmonary melanoma nodes, respectively.

Hybrid multimodal nanoparticles, applicable simultaneously to the noninvasive imaging and therapeutic treatment, are highly demanded for clinical use. Here, Fe-Au core-satellite nanoparticles prepared by the method of pulsed laser ablation in liquids were evaluated as dual magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents and as sensitizers for laser-induced hyperthermia of cancer cells. The biocompatibility of Fe-Au nanoparticles was improved by coating with polyacrylic acid, which provided excellent colloidal stability of nanoparticles with highly negative ζ-potential in water (−38 ± 7 mV) and retained hydrodynamic size (88 ± 20 nm) in a physiological environment. The ferromagnetic iron cores offered great contrast in MRI images with r₂ = 11.8 ± 0.8 mM⁻¹ s⁻¹ (at 1 T), while Au satellites showed X-ray attenuation in CT. The intravenous injection of nanoparticles enabled clear tumor border visualization in mice. Plasmonic peak in the Fe-Au hybrids had a tail in the near-infrared region (NIR), allowing them to cause hyperthermia under 808 nm laser exposure. Under NIR irradiation Fe-Au particles provided 24.1 °C/W heating and an IC₅₀ value below 32 µg/mL for three different cancer cell lines. Taken together, these results show that laser synthesized Fe-Au core-satellite nanoparticles are excellent theranostic agents with multimodal imaging and photothermal capabilities.

One of the challenges of the medicine is to improve the chemical stability of drugs and to prevent their premature biodegradation before reaching the therapeutic target. Various nanoparticles were used to solve this problem, but low drug loading efficiency limited their biomedical applications. Metal organic frameworks are promising candidates for drug delivery since they have extremely high surface area and regular porosity. In this study, we prepared high-crystalline MIL-53 frameworks based on aluminium and 2-aminoterephtalic acid by microwave-assisted synthesis and evaluated their properties as drug carriers. Drug loading of chemotherapeutic and diagnostic molecules of different nature riches value of 34% by particle weight, significantly higher than those of other reported solid nanoparticles. Therefore, our results make MIL-53 (Al) frameworks promising candidate for drug delivery.

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 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 nanoparticles as low as 1 mg/L. 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.