Mix-and-read bioluminescent copper detection platform using a caged coelenterazine analogue

Area of Science:

• Biochemistry
• Analytical Chemistry
• Medical Diagnostics

Background:

• Serum copper levels are key biomarkers for diseases like Wilson's disease.
• Accurate quantification of free copper in serum is crucial for diagnosis.
• Existing bioluminescence assays often require genetically engineered luciferase, limiting point-of-care applications.

Purpose of the Study:

• To develop a novel, luciferase-independent platform for detecting copper ions in human serum.
• To design and synthesize a caged coelenterazine analogue for sensitive and specific copper detection.
• To enable a simple "mix-and-read" assay for free copper quantification.

Main Methods:

• Design and synthesis of a luminogenic caged coelenterazine analogue, TPA-H1, featuring a copper(I)-cleavable tris[(2-pyridyl)-methyl]amine (TPA) ligand.
• Utilizing the TPA-H1 scaffold, a novel luciferin, HuLumino1, is produced upon copper ion cleavage.
• Demonstrating "turn-on" bioluminescence of HuLumino1 specifically with human serum albumin for quantitative analysis.

Main Results:

• TPA-H1 demonstrated rapid cleavage of its caging group by copper ions.
• The assay exhibited high specificity and sensitivity for copper over other metal ions.
• The developed method allows for simple, "mix-and-read" detection of free copper in human serum.

Conclusions:

• The novel caged coelenterazine derivative, TPA-H1, provides a luciferase-independent method for copper detection.
• This platform offers a sensitive, specific, and rapid approach for quantifying free copper in serum.
• The TPA-H1 assay holds potential for point-of-care diagnostics of copper-related diseases.