Zinc-Porphyrin Terephthalate-Based Metal-Organic Framework: Structural Insights and Functional Antibacterial...

Area of Science:

• Materials Science
• Nanotechnology
• Photochemistry

Background:

• Antibiotic resistance necessitates novel therapeutic strategies.
• Metal-organic frameworks (MOFs) offer tunable properties for various applications.
• Porphyrin-based materials are investigated for photodynamic therapy.

Purpose of the Study:

• To synthesize and characterize a mixed-linker zinc-based MOF (compound 2) for antibacterial photodynamic therapy.
• To compare its efficacy against a known porphyrin (compound 1).
• To elucidate the structure-property relationships governing its antibacterial activity.

Main Methods:

• Synthesis and crystal structure analysis of protonated 5,10,15,20-tetrakis(4-pyridyl)porphyrin (compound 1) and zinc-based MOF (compound 2).
• Surface area measurement using N2 adsorption.
• Molecular orbital calculations.
• Antibacterial photodynamic therapy assays under red light irradiation.

Main Results:

• Compound 2 forms an interpenetrated 3D framework with a high theoretical surface area (2915 m² g⁻¹).
• Molecular orbital calculations indicate porphyrin core localization of frontier orbitals.
• Compound 2 demonstrated enhanced reactive oxygen species production and superior antibacterial activity against MRSA and E. coli compared to compound 1.
• Significant inhibition zones of 28±1 mm (MRSA) and 21±1 mm (E. coli) were observed for compound 2.

Conclusions:

• The synthesized zinc-based MOF (compound 2) is a promising light-activated antibacterial platform.
• Its enhanced performance is attributed to its structure and electronic properties.
• This study provides a rational design approach for next-generation antibacterial agents.