Positively Charged AIE Luminogen for Cardiolipin Detection
Solution Overview
Problem
Current methods for quantifying cardiolipin (CL) are inefficient, lacking a standard protocol, requiring extra substrates, and involving sophisticated instrumentation, making specific detection among numerous phospholipids challenging, especially in biological systems where conventional dyes like NAO suffer from poor water-solubility and unclear working mechanisms.
Innovation Solution
The use of positively charged aggregation-induced emission (AIE) luminogens, such as TTAPE-Me, which become highly fluorescent when aggregated, allowing for one-step detection and quantification of cardiolipin in samples by measuring fluorescence intensity, and enabling visualization and quantification of isolated mitochondria with enhanced sensitivity and selectivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional fluorescent dyes like NAO are used for cardiolipin detection, then fluorescence signal can be obtained, but the method suffers from poor water-solubility, small Stokes shift, and requires complex protocols including fixation, long incubation, and centrifugation
Solution Approach 1:
The patent changes the molecular structure parameters of the fluorescent dye by developing AIE luminogens with specific tetraphenylethene cores and electron-donating/withdrawing groups. This structural modification enables the dye to exhibit aggregation-induced emission characteristics, turning off fluorescence in aqueous solution and turning on fluorescence upon aggregation with cardiolipin, thereby eliminating the need for complex protocols while maintaining detection sensitivity
Solution Approach 2:
The patent replaces the mechanical operations (fixation, centrifugation, multiple washing steps) with a direct fluorescence-based detection method. The AIE luminogen directly binds to cardiolipin in the sample without requiring mechanical separation or fixation steps, substituting complex mechanical protocols with a simple optical measurement
2Measurement precision
If LC-MS is used for lipidomics profiling to quantify cardiolipin, then quantitative analysis can be achieved, but sophisticated instrumentation and experienced operators are required, limiting application scope
Solution Approach 1:
The patent replaces expensive, sophisticated LC-MS instrumentation with a simple, inexpensive fluorescence measurement system. The AIE luminogen serves as a disposable probe that can be directly added to samples, and the measurement is performed using accessible fluorescence spectrophotometers or plate readers, eliminating the need for complex mass spectrometry equipment and specialized operators
Solution Approach 2:
The patent introduces an intermediary substance (AIE luminogen) that mediates between the target analyte (cardiolipin) and the detection system. The luminogen specifically binds to cardiolipin and translates its presence into a measurable fluorescence signal, serving as a bridge that simplifies the detection process while maintaining quantification accuracy
3Ease of manufacture
If NAO is used for mitochondria staining, then mitochondria can be visualized, but tortuous steps including fixation, long time incubation, and centrifugation are involved
Solution Approach 1:
The AIE luminogen is designed to be pre-formulated in a ready-to-use state, eliminating the need for complex preparation steps. The dye can be directly added to the sample without requiring prior fixation or activation steps, enabling immediate staining and significantly reducing the overall processing time
4Measurement precision
If NAO is used for cardiolipin quantification, then fluorescence signal is obtained, but both excitation and emission maxima are dependent on dye concentration, and linear relationship is established only at specific NAO/CL molar ratio
Solution Approach 1:
The patent changes the optical parameters of the fluorescent probe by utilizing AIE luminogens with large Stokes shifts. This ensures that both excitation and emission maxima are independent of dye concentration, and the fluorescence intensity maintains a linear relationship with cardiolipin concentration across a wide range of conditions, eliminating the need for precise molar ratio control and simplifying the measurement procedure
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 provides a simple, sensitive, and selective method for quantifying cardiolipin and isolated mitochondria, overcoming the limitations of existing techniques with improved sensitivity and selectivity, and does not require complex protocols or instrumentation, offering potential for clinical diagnosis and research applications.
Implementation Method 1
luminogens with aggregation-induced emission (AIE) characteristics have attracted attention. As opposed to conventional dyes, AIE luminogens are non-emissive when molecularly dissolved, but become highly fluorescent in the aggregate state, due to the restriction of intramolecular motions.
Implementation Method 2
measuring fluorescence intensity of the solution
Data Source
AI summary
The present subject matter relates to a one-step method of detecting and quantifying cardiolipin in a sample using a positively charged AIE luminogen by introducing the AIE luminogen to a solution containing the sample and measuring fluorescence intensity of the solution; a method of quantifying isolated mitochondria using a positively charged AIE luminogen by staining a sample containing isolated mitochondria with the AIE luminogen and measuring the fluorescence intensity; and a method of quantifying isolated mitochondria using a positively charged AIE luminogen by introducing the AIE luminogen to a sample containing isolated mitochondria, wherein the AIE luminogen stains the isolated mitochondria and identifying the stained isolated mitochondria under microscope. With improved sensitivity and excellent selectivity to CL over other major mitochondrial membrane lipids, an aggregation-induced emission-active fluorogen, TTAPE-Me, may serve as a valuable fluorescent sensor for CL detection and quantification and the quantification of isolated mitochondria.