Ratiometric Fluorescence Coding for Multiplex Nucleic Acid Amplification Testing.

Area of Science:

• Molecular Biology
• Biotechnology
• Medical Diagnostics

Background:

• Nucleic acid amplification testing (NAAT) is crucial for molecular disease diagnosis.
• Current multiplexed NAAT methods using one fluorophore per target are limited by spectral overlap.
• Expanding detection capacity in NAAT is a key objective for improved diagnostics.

Purpose of the Study:

• To develop a novel multiplexed detection approach for NAAT.
• To overcome the limitations of spectral overlap in current multiplexing strategies.
• To enhance the capacity for simultaneous detection of multiple nucleic acid targets.

Main Methods:

• Introduced ratiometric fluorescence coding, encoding targets with specific ratios of two fluorophores.
• Utilized padlock probe chemistry to create specific binding sites for differentially labeled probes.
• Coupled padlock probes with rolling circle amplification (RCA) or hyperbranched RCA (HRCA) for signal amplification.

Main Results:

• Demonstrated multiplexed detection of DNA targets from six infectious diseases.
• Achieved specific target encoding through predesigned ratios of two fluorescent probes.
• Showcased the potential for significantly expanding multiplexing capabilities beyond current methods.

Conclusions:

• Ratiometric fluorescence coding offers a promising new strategy for highly multiplexed NAAT.
• This approach overcomes spectral limitations inherent in one-target-one-fluorophore methods.
• Further development could greatly facilitate molecular diagnosis of a wider range of diseases.