Universal Reference Dye for PCR Signal Normalization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current real-time PCR systems face challenges in data normalization due to differences in passive reference dye concentrations across various instruments, leading to inefficiencies in signal generation and accuracy, particularly with instruments like the AB7900 requiring high ROX concentrations for proper normalization.
Innovation Solution
A reaction mixture comprising a first passive reference dye, such as 5- or 6-carboxy-X-rhodamine, and a second passive reference dye with a Stokes-shift of at least 60 nm, allowing for compatible signal normalization across both high and low ROX concentration platforms, using a fluorescent dye like Chromeo 494 or DY-510XL with a long Stokes-shift to generate sufficient signal for normalization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high concentration of passive reference dye (e.g., ROX) is used for normalization, then sufficient signal for proper normalization is generated on high-Rox instruments, but the reaction mixture is not compatible with low-Rox instruments and requires instrument-specific formulation
Solution Approach 1:
The passive reference dye signal is segmented into two independent components: a first passive reference dye (e.g., ROX) providing baseline normalization signal, and a second passive reference dye with long Stokes-shift providing additional excitable signal. Each dye component can be independently optimized for different instrument types, allowing the same mixture to work across both high-Rox and low-Rox platforms.
Solution Approach 2:
The reaction mixture uses a composite dye system combining two different passive reference dyes with distinct photophysical properties. The first dye (e.g., ROX) has standard excitation/emission characteristics, while the second dye has a long Stokes-shift allowing excitation at different wavelengths. This composite approach creates a universal mixture that generates adequate reference signal across varying instrument configurations.
2Measurement precision
If different passive reference dye concentrations are used for different instruments, then each instrument platform achieves optimal normalization performance, but multiple instrument-specific reaction mixtures must be maintained and managed
Solution Approach 1:
The reaction mixture is designed with universal applicability across different instrument platforms by incorporating two passive reference dyes with complementary properties. The mixture can function on both high-Rox instruments (where the first dye dominates) and low-Rox instruments (where the second dye with long Stokes-shift provides sufficient signal), eliminating the need for platform-specific formulations and simplifying workflow management.
3Measurement precision
If passive reference dye concentration is optimized for one instrument platform, then accurate Ct values are obtained on that platform, but the same mixture produces insufficient reference signal on platforms with different excitation characteristics
Solution Approach 1:
The reaction mixture accounts for parameter variations across instrument platforms by incorporating dyes with different excitation and emission characteristics. The first passive reference dye optimizes performance on high-Rox platforms, while the second dye with long Stokes-shift compensates on low-Rox platforms, ensuring adequate reference signal and accurate Ct values across all platforms without requiring platform-specific optimization.
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 solution enables universal use of a single reaction mixture across different PCR instruments, eliminating the need for additional reagents and reducing errors by ensuring accurate normalization and reproducibility of data, regardless of the instrument's ROX concentration settings.
Implementation Method 1
the mixture comprises a plurality of passive reference dyes that produce fluorescent signals independent of the amplification reactions
Implementation Method 2
a first passive reference dye having a Stokes-shift, wherein the first passive reference dye is at a concentration sufficient for use in low concentration passive reference dye normalization
Data Source
AI summary
The present invention provides for a reaction mixture for signal normalization in a real-time polymerase chain reaction (PCR) amplification of a target nucleic acid wherein the mixture is compatible for use in both (a) a real-time PCR amplification system employing high passive reference dye concentration for the normalization and (b) a real-time peR30 amplification system employing low passive reference dye concentration for the normalization, wherein the mixture comprises a plurality of passive reference dyes that produces fluorescent signals independent of the amplification reactions.