Description
Surface-functional biosensor recognition ligand designed for selective detection of Human Serum Albumin (HSA), supplied as a thiol-modified DNA aptamer for direct immobilization on gold and thiol-reactive sensor surfaces. Engineered for high binding specificity, controlled probe orientation, and stable integration into electrochemical and microfluidic biosensor platforms. For Research Use Only (RUO).
Product Description
The ProbeSeq Human Serum Albumin BiosensorProbe™ is a thiol-functionalized single-stranded DNA aptamer engineered for selective recognition and capture of human serum albumin, the most abundant plasma protein and a key biomarker for liver function, kidney disease, metabolic disorders, and vascular leakage monitoring. The probe incorporates a terminal sulfhydryl (–SH) functional group enabling stable covalent immobilization on gold sensor interfaces while maintaining aptamer folding and binding activity.
Human serum albumin is a transport protein (~66.5 kDa) typically present in blood at concentrations of 35–50 g/L and in urine at <30 mg/day under normal conditions. Elevated urinary albumin or altered serum levels indicate renal dysfunction, cardiovascular disease risk, or hepatic 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, optical, and impedance sensing platforms.
Recognition Mechanism
Target recognition is mediated by a sequence-engineered single-stranded DNA aptamer (~40–75 nucleotides) forming a selective binding structure specific to albumin surface domains through hydrogen bonding, hydrophobic interactions, and electrostatic complementarity.
Binding affinity (Kd): 0.5–10 nM
Detection range: ng/mL to mg/mL depending on sensor configuration
Association kinetics: rapid binding within seconds
Reversible binding suitable for continuous monitoring applications
Specificity and Selectivity
The HSA BiosensorProbe™ demonstrates high specificity toward human serum albumin with minimal cross-reactivity toward bovine serum albumin and other plasma proteins.
Cross-reactivity: <5% against related serum proteins
Non-specific adsorption reduction: >90% vs non-functionalized DNA
Matrix compatibility: serum, plasma, urine, and interstitial fluid
Molecular Format and Functionalization
Synthetic single-stranded DNA aptamer containing terminal thiol functional group.
Aptamer length: ~40–75 nucleotides
Functionalization efficiency: ≥95% thiol incorporation
Purity: ≥95% (HPLC verified)
End modification: 5′ C6-thiol linker
Buffer formulation: nuclease-free buffered solution
Surface Immobilization Chemistry
Terminal thiol enables formation of self-assembled monolayers 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 diagnostic devices
Wearable biosensing platforms
Performance Characteristics
Binding affinity: 0.5–10 nM
Surface coverage: 10¹²–10¹³ molecules/cm²
Operating temperature: 4–45°C
Low non-specific adsorption
Stable signal response during continuous measurement
Stability
Shelf stability: ≥12 months at −20°C
Working stability after immobilization: ≥14 days
Thermal tolerance: stable up to ~60°C short exposure
Storage
Store at −20°C in supplied buffer. Avoid repeated freeze–thaw cycles. Protect from oxidation and light.
Applications
Kidney function monitoring
Liver disease assessment
Urinary albumin detection
Wearable health monitoring
Electrochemical biosensor development
Microfluidic diagnostic systems
