High-affinity ssDNA aptamer and chemiluminescent aptasensor for TIMP-1 detection in human serum

Area of Science:

• Biochemistry
• Molecular Biology
• Biomarker Discovery

Background:

• Tissue Inhibitor of Metalloproteinases-1 (TIMP-1) regulates extracellular matrix degradation and is a crucial cancer biomarker.
• Developing targeted molecules for TIMP-1 is essential for advancing cancer diagnostics.

Purpose of the Study:

• To develop and characterize a single-stranded DNA (ssDNA) aptamer with high affinity and specificity for human TIMP-1.
• To create a sensitive detection platform for TIMP-1 using the developed aptamer.

Main Methods:

• Systematic Evolution of Ligands by Exponential Enrichment (SELEX) using magnetic beads and quantitative Polymerase Chain Reaction (qPCR) for aptamer selection.
• High-throughput sequencing for candidate identification, and Surface Plasmon Resonance (SPR) for affinity and specificity characterization.
• Development of a chemiluminescent aptasensor for TIMP-1 detection in human serum.

Main Results:

• A high-affinity ssDNA aptamer targeting TIMP-1 was selected, exhibiting a dissociation equilibrium constant (K_D) of 0.41 nM and a slow off-rate.
• The aptamer demonstrated effective capture of TIMP-1 from serum samples.
• The developed chemiluminescent aptasensor showed high specificity and a linear detection range of 1–500 ng/mL in human serum.

Conclusions:

• The novel ssDNA aptamer exhibits excellent affinity and specificity for TIMP-1.
• The chemiluminescent aptasensor presents a promising tool for the clinical diagnosis of TIMP-1 levels in human serum.