A Versatile Colorimetric Diagnostic Platform Based on Primer Exchange Reaction Cascades Driven Loop-Mediated...

Area of Science:

• Biotechnology
• Molecular Diagnostics
• Isothermal Nucleic Acid Amplification

Background:

• Conventional primer exchange reaction (PER) has limitations in amplification efficiency due to its linear signal amplification.
• There is a need for sensitive and rapid detection methods for cancer biomarkers like microRNAs (miRNAs) and carcinoembryonic antigen (CEA).

Purpose of the Study:

• To develop a versatile colorimetric platform by integrating PER with loop-mediated isothermal amplification (LAMP), termed vcPeLa.
• To achieve rapid and sensitive detection of cancer biomarkers (miRNAs and CEA) using the developed vcPeLa platform.

Main Methods:

• The vcPeLa platform integrates PER for target-initiated DNA amplification with LAMP.
• PER produces single-stranded DNA products that serve as templates for LAMP, generating double stem-loop DNAs.
• A pyrophosphate sensing probe detects pyrophosphate produced during LAMP, leading to a colorimetric signal.

Main Results:

• The vcPeLa platform demonstrated ultrasensitive detection of miRNA at 0.31 fM and CEA at 0.043 ng/mL.
• The assay exhibited high selectivity and stability for cancer biomarker detection.
• The method eliminates the need for additional reaction steps or sample transfers, simplifying the process.

Conclusions:

• The facile and ultrasensitive vcPeLa platform offers a promising new tool for cancer diagnosis.
• This integrated approach enhances amplification efficiency compared to conventional PER.
• The colorimetric nature of vcPeLa facilitates rapid and straightforward biomarker screening.