Description
Surface-functional biosensor recognition ligand designed for selective detection of Transforming Growth Factor Beta (TGF-β), supplied as a thiol-modified DNA aptamer for direct immobilization on gold and thiol-reactive sensor surfaces. Engineered for high binding specificity, low non-specific adsorption, and stable integration into electrochemical and microfluidic biosensor platforms. For Research Use Only (RUO).
Product Description
The ProbeSeq Transforming Growth Factor Beta BiosensorProbe™ is a thiol-functionalized single-stranded DNA aptamer engineered for selective recognition and capture of TGF-β, a multifunctional cytokine involved in immune regulation, tissue remodeling, fibrosis, and tumor progression. The probe incorporates a terminal sulfhydryl (–SH) functional group enabling stable covalent immobilization on gold sensor interfaces while maintaining structural folding and target-binding activity.
TGF-β is a secreted dimeric cytokine (~25 kDa active form) present in serum typically at 1–10 ng/mL and elevated in cancer, fibrosis, and inflammatory disorders. The BiosensorProbe™ supports quantitative detection across clinically relevant concentration ranges.
The probe enables high-density surface immobilization (~10¹²–10¹³ molecules/cm²), controlled probe orientation, and stable signal generation across electrochemical, impedance, and microfluidic sensing systems.
Recognition Mechanism
Target recognition is mediated by a sequence-engineered single-stranded DNA aptamer (~45–80 nucleotides) that forms a selective binding structure recognizing TGF-β protein epitopes through hydrogen bonding and electrostatic interactions.
Binding affinity (Kd): 0.1–3 nM
Detection range: pg/mL to ng/mL
Association kinetics: seconds to minutes
Reversible conformational binding suitable for quantitative biosensing
Specificity and Selectivity
The TGF-β BiosensorProbe™ demonstrates high specificity toward TGF-β with minimal cross-reactivity toward related cytokines including IL-10, IL-6, and PDGF.
Cross-reactivity: <5%
Non-specific adsorption reduction: >90% vs non-functionalized DNA
Matrix compatibility: serum, plasma, saliva, and cell culture media
Molecular Format and Functionalization
Synthetic single-stranded DNA aptamer with terminal thiol modification for covalent surface attachment.
Aptamer length: ~45–80 nucleotides
Functionalization efficiency: ≥95% thiol incorporation
Purity: ≥95% (HPLC verified)
End modification: 5′ C6-thiol linker
Buffer formulation: nuclease-free solution
Surface Immobilization Chemistry
Terminal thiol enables self-assembled monolayer formation on gold surfaces via Au–S bonding.
Surface binding strength: ~40–50 kcal/mol
Immobilization time: 30–120 min
Recommended surface density: 1–10 pmol/cm²
Operating pH after immobilization: 6.5–8.5
Compatible Sensor Surfaces
Gold electrodes and nanostructured gold substrates
Gold nanoparticle-modified interfaces
Thiol-reactive polymer coatings
Maleimide-functionalized surfaces
Electrochemical and impedance biosensors
Microfluidic lab-on-chip systems
Wearable biosensing devices
Performance Characteristics
Binding affinity: 0.1–3 nM
Surface coverage: 10¹²–10¹³ molecules/cm²
Operating temperature: 4–45°C
Low non-specific adsorption
Stable signal across repeated measurements
Stability
Shelf stability: ≥12 months at −20°C
Working stability after immobilization: ≥7–14 days
Thermal tolerance: stable up to ~60°C short exposure
Storage
Store at −20°C in supplied buffer. Avoid repeated freeze–thaw cycles and oxidation. Protect from light.
Applications
Cancer progression monitoring
Fibrosis biomarker detection
Immunology research
Cytokine profiling platforms
Electrochemical biosensor development
Microfluidic diagnostic systems
