Fluorogenic Molecular Linkers for Chemoselective Bioconjugation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current bioconjugation methods lack chemoselectivity and efficiency, often resulting in high background signals and toxicity, making them unsuitable for biomedical applications, particularly in vivo imaging and drug delivery, where specific and sensitive detection of conjugation is required.
Innovation Solution
A novel method involving the reaction of a first linkage compound with a structure A-(Y)y—N3 or A-(Y)y—X and a second linkage compound with a structure E-(Z)z—C≡CRE or E-(Z)z—C≡N, using azide salts, to form a fluorescent linkage complex that is distinct from the starting compounds, allowing for chemoselective and biocompatible conjugation under mild conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional bioconjugation methods using electrophiles and nucleophiles are employed, then conjugation can be achieved, but chemoselectivity is poor and background signals are high
Solution Approach 1:
The patent changes the chemical reaction parameters by using copper-catalyzed azide-alkyne cycloaddition instead of conventional electrophile-nucleophile reactions. This parameter change achieves high chemoselectivity because azides and alkynes are chemically orthogonal to most biological functional groups, eliminating cross-reactivity and background signals while maintaining conjugation efficiency
Solution Approach 2:
The patent creates an inert chemical environment by using azide and alkyne functional groups that are chemically inert toward most biological molecules. This inert environment prevents unwanted side reactions with proteins, nucleic acids, and other cellular components, thereby eliminating background signals while allowing specific conjugation at the azide-alkyne interface
2Measurement precision
If multistep labeling procedures are used, then detectable tags can be attached, but excess reagents are hard to remove and procedures become complex
Solution Approach 1:
The patent merges the conjugation step and the detection step into a single unified process. The fluorescent probe contains both the alkyne/azide functional group for chemoselective conjugation and the fluorophore for detection. This merging eliminates the need for separate labeling and detection steps, simplifying the procedure while maintaining high detection sensitivity
Solution Approach 2:
The fluorescent probe is designed with multi-functionality, serving both as a conjugation reagent (through its alkyne or azide group) and as a detection agent (through its fluorophore). This universal design allows a single reagent to perform multiple functions that previously required separate steps, reducing procedural complexity while preserving detection sensitivity
3Measurement precision
If biarsenical fluorophores are used for high affinity binding, then strong fluorescent signals are achieved, but high concentrations are needed and toxicity increases
Solution Approach 1:
The patent uses biocompatible azide and alkyne functional groups that are non-toxic and can be used at low concentrations. These functional groups act as disposable, biologically inert handles that enable conjugation without the toxicity and high concentration requirements of biarsenical compounds, while still achieving strong fluorescent signals through the attached fluorophore
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
This approach enables a one-step, chemoselective bioconjugation process that provides a strong fluorescent signal only upon successful linkage, minimizing background noise and maintaining biological compatibility, facilitating sensitive and specific detection of conjugation events.
Implementation Method 1
The present invention is directed to a novel method of forming a linkage complex having a fluorescent signal, the method comprising: contacting a first linkage compound having the structure A-(Y)y—N3, or A-(Y)y—X; with a second linkage compound having the structure E-(Z)z—C≡CRE, or E-(Z)z—C≡N; to form a linkage complex having a fluorescent signal
Implementation Method 2
at least one of A and E is a fluorophore, and any A or E that is not a fluorophore is an organic or inorganic group
Data Source
AI summary
The present invention describes a bioconjugation strategy and compounds that are useful therein in which a fluorescent signal is produced when two molecular or supramolecular entities are linked by chemoselective combination of one linker having an azido or halide substituent group with another linker having a cyano or an alkyne substituent group. A kit is also provided.