Biomimetic iron and copper complexes for antimicrobial applications inspired by the immune response

Overview

This research proposes a novel antimicrobial approach that mimics the mammalian immune response by generating reactive nitrogen species (RNS) and reactive oxygen species (ROS) outside the cell. Rather than relying on traditional antibiotics or harsh chemical disinfectants, the technology uses environmentally benign iron and copper complexes to produce these germ-killing species in situ. The work leverages the well-known antimicrobial activity of nitric oxide (NO) and the subsequent generation of RNS and ROS through reaction with atmospheric oxygen. Because oxygen concentration is significantly higher outside the cell than within it, this biomimetic approach can achieve potent antimicrobial effects without introducing toxic or persistent chemicals into the environment.

Technical specifications

Core chemistry:

• Dinitrosyl iron complexes (DNICs): non-heme iron complexes with established O2 reactivity that produce peroxynitrite, a powerful oxidant, along with controlled NO-releasing properties
• Roussin's black salt (RBS): iron nitrosyl complex with known antimicrobial activity
• Roussin's red esters (RREs): iron nitrosyl complexes capable of releasing NO
• Copper catalysts: designed to produce hydrogen peroxide (H2O2) from atmospheric O2, boosting overall ROS levels

Key features:

• Environmentally benign metal complexes replace conventional antimicrobial agents
• In situ generation of RNS and ROS mimics natural immune defense chemistry
• Ambient oxygen serves as the oxidant source, enabling passive antimicrobial activity
• Modular design allows tuning of iron and copper complex formulations for different product applications

Technology readiness level

The proposed research is at an early-to-mid stage of development. The underlying chemistry of DNICs, RBS, and RREs has been characterized by the research group, which is a recognized leader in DNIC chemistry. O2 reactivity and NO-releasing properties of DNICs have already been reported. Future validation will focus on developing a defined group of iron nitrosyl complexes suitable for incorporation into consumer products, combined with copper catalysts that enhance ROS generation. Further testing is needed to confirm efficacy, stability, and safety profiles in real-world product formulations before commercial deployment.