An electrochemiluminescence microsensor based on DNA-silver nanoclusters amplification for detecting cellular...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Molecular Biology

Background:

• Adenosine triphosphate (ATP) is essential for cellular energy and function.
• Accurate and rapid ATP level assessment is critical for cellular event analysis.
• Existing ATP assays often require complex sample preparation and lack portability.

Purpose of the Study:

• To develop a portable and integrated electrochemiluminescence (ECL) microsensor array for sensitive cellular ATP detection.
• To utilize a closed bipolar electrode (BPE) design for efficient separation of ECL reagents and sensing components.
• To establish a novel detection mechanism based on aptamer-ssDNA interaction, rolling circle amplification (RCA), and silver nanocluster (Ag NC) generation.

Main Methods:

• Fabrication of a closed bipolar electrode (BPE) based ECL microsensor array.
• Assembly of ATP aptamer with single-stranded DNA (ssDNA) in the sensing chamber.
• ATP-induced aptamer disassembly, triggering DNA-templated silver nanocluster (Ag NC) generation via RCA.
• Enhancement of BPE conductivity and ECL signal through in situ Ag NC formation.

Main Results:

• Achieved a good linear relationship for ATP detection from 30 to 1000 nM.
• Demonstrated selective and sensitive determination of ATP content in HepG2 cells.
• Successfully detected ATP from as few as 25 cells using a sub-microliter sample volume.

Conclusions:

• The developed ECL microsensor provides an efficient and sensitive platform for cellular ATP quantification.
• The BPE design and RCA-triggered Ag NC generation offer a novel approach for biosensing applications.
• This portable assay enables rapid ATP level evaluation in biological samples without extensive pretreatment.