Metal-Based Coordination Complexes for Hypoxic Photodynamic Therapy

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

There is a need for new photodynamic compounds (PDCs) that can effectively treat diseases caused by hyperproliferating cells, such as cancer, and function as both therapeutic and diagnostic agents, particularly those that can be activated by light in various environments, including hypoxic conditions, and are capable of inducing apoptosis and DNA crosslinking.

Innovation Solution

Development of novel metal-based coordination complexes derived from organic ligands, specifically tunable compounds that include osmium, manganese, molybdenum, rhenium, ruthenium, rhodium, iridium, nickel, and platinum, which can absorb UV-IR light, including near-infrared, to destroy hyperproliferative cells, microbial cells, and viruses, and function as DNA binding agents, photocleavage agents, and photosensitizers capable of Type I and Type II photoprocesses.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional organic-based porphyrins are used as photodynamic compounds, then they can provide photosensitizing activity, but they have limitations in effectiveness under hypoxic conditions and lack disease-modifying properties

Engineering Contradiction:
Improveeffectiveness under hypoxic conditionsVSAvoiddisease-modifying capability
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent employs metal-based coordination complexes that combine metal centers (Ru, Rh, Ir, Os, Pt) with organic ligands to create composite photodynamic compounds. These composite structures integrate the photosensitizing properties of organic ligands with the catalytic and stability properties of metal centers, enabling effective operation under hypoxic conditions through alternative photoprocesses (Type I mechanisms) while providing disease-modifying effects through DNA binding and crosslinking capabilities.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent utilizes metal-based coordination complexes that can undergo photoprocesses independent of oxygen concentration (Type I mechanisms involving radical species), fundamentally changing the operational parameters from oxygen-dependent (Type II) to oxygen-independent pathways. This parameter change enables reliable photodynamic activity under hypoxic conditions where traditional porphyrins fail.

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If photodynamic compounds are designed to function in various oxygen conditions, then they can treat hypoxic tumors, but they require complex metal-based coordination structures

Engineering Contradiction:
Improvefunctionality under different oxygen conditionsVSAvoidmolecular structure complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The metal-based coordination complexes are designed to perform multiple functions: photosensitizing under both normoxic and hypoxic conditions, DNA binding, DNA crosslinking, and photocleavage. This multi-functionality is achieved through the versatile coordination chemistry of transition metals that can engage in both photoprocesses and direct biological interactions, reducing the need for separate therapeutic mechanisms.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The coordination complexes combine metal centers with tailored organic ligands to create composite structures that integrate photosensitizing, DNA-binding, and crosslinking functionalities into a single molecular entity, achieving versatility without requiring multiple separate compounds.

Inventive Principle:
Principle #40Composite materials

3Adaptability or versatility

If photodynamic compounds induce DNA crosslinking and apoptosis, then they provide disease-modifying effects, but they may increase toxicity to normal cells

Engineering Contradiction:
Improvedisease-modifying effectVSAvoidtoxicity to normal cells
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The metal-based coordination complexes bind to DNA and form stable complexes before light activation. This preliminary binding localizes the photodynamic activity specifically at the DNA location, ensuring that upon light irradiation, the photochemical reactions (crosslinking, cleavage) occur only where the complex is bound, thereby protecting normal cells from off-target toxicity while maintaining disease-modifying effects in target cells.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The metal-based coordination complexes act as intermediaries that mediate between light energy and DNA. They absorb light and transfer energy to produce reactive species or directly induce photochemical changes in DNA, providing a controlled and localized mechanism for disease modification that reduces uncontrolled toxicity to normal tissues.

Inventive Principle:
Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

These compounds demonstrate high stability, effectiveness in photodynamic therapy (PDT) under different oxygen conditions, inducing cell death in cancer cells and bacteria, and show promise as both therapeutic and diagnostic agents, with potential for in vivo applications.

Implementation Method 1

The photodynamic compounds can be activated with ultraviolet to infrared (UV-IR) light, particularly near infrared light... The photodynamic compounds can be activated by light to destroy unwanted cells

Methodology Applied
Scientific EffectPhotodynamic therapy: Photosynthesis

Implementation Method 2

The compounds are useful as DNA binding agents... inducing cell death in cancer cells and bacteria

Methodology Applied
Scientific EffectDNA binding: Adsorption

Implementation Method 3

The compounds are useful as photocleavage agents... capable of Type I and Type II photoprocesses

Methodology Applied
Scientific EffectPhotocleavage: Photodissociation

Data Source

PatentEP2976347B1Metal-based coordination complexes as photodynamic compounds and their use
Publication Date: 2022.01.19 MCFARLAND SHERRI ANN
  • EP2976347B1 patent drawingFigure 1
  • EP2976347B1 patent drawingFigure 2~3
  • EP2976347B1 patent drawingFigure 4~5

AI summary

Compositions of the invention include metal-based coordination complexes, which are preferably tunable photodynamic compounds. The compositions and complexes are useful as therapeutic agents and as in vivo diagnostic agents for treating or preventing diseases including those that involve hyperproliferating cells in their etiology, such as cancer. Compositions and complexes of the invention are further capable of destroying microbial cells, such as bacteria, fungi, and protozoa, and destroying viruses. The compositions and complexes are also capable of modulating cell function in other ways.