Beyond Porosity: Reframing Metal-Organic Frameworks in Biomedicine as Dynamic, Biologically Active Materials

Area of Science:

• Biomaterials Science
• Nanotechnology
• Coordination Chemistry

Background:

• Metal-organic frameworks (MOFs) possess permanent porosity, initially making them attractive for biomedical applications like drug delivery.
• The prevailing view considered MOFs as passive carriers for cargo loading, protection, and release.

Purpose of the Study:

• To challenge the notion of biomedical MOFs as biologically inert carriers.
• To highlight the dynamic and programmable nature of MOFs in biological environments.
• To propose a shift towards engineering MOFs that leverage their inherent bioactivity.

Main Methods:

• Conceptual analysis of MOF behavior in biological settings.
• Examination of MOF properties including coordinated disassembly, particle transport, and framework-derived activity.
• Evaluation of MOF performance beyond traditional metrics like surface area and pore volume.

Main Results:

• Biomedical MOFs are metastable, dynamic coordination materials, not inert carriers.
• MOF composition, structure, and environmental transformations significantly influence biological outcomes.
• MOF performance is poorly described by surface area, pore volume, and loading capacity alone.

Conclusions:

• MOF bioactivity, including disassembly and compositional effects, should be embraced and engineered.
• Future biomedical MOF development should focus on dynamic materials that actively shape biological responses.
• This paradigm shift moves beyond passive delivery systems to programmable therapeutic agents.