Description
Surface-functional biosensor recognition ligand designed for selective detection of C-Reactive Protein (CRP), supplied as a thiol-modified DNA aptamer for direct immobilization on gold and thiol-reactive sensor surfaces. Engineered for controlled orientation, high binding specificity, and stable integration into electrochemical and microfluidic biosensor platforms. For Research Use Only (RUO).
Product Description
The ProbeSeq CRP BiosensorProbe™ is a thiol-functionalized DNA aptamer engineered for selective recognition and capture of C-Reactive Protein (CRP), a clinically important acute-phase inflammatory biomarker widely used in infection monitoring, cardiovascular risk assessment, and inflammation diagnostics. The probe incorporates a terminal sulfhydryl (–SH) functional group that enables controlled covalent attachment to gold and thiol-reactive sensor interfaces while preserving aptamer folding and target-binding activity.
C-Reactive Protein is a pentameric protein complex (~115 kDa) composed of five identical subunits arranged in a cyclic structure. Its multivalent architecture enables strong interactions with engineered recognition ligands and supports highly sensitive surface-based detection. The CRP BiosensorProbe™ is optimized for surface-immobilized sensing environments, allowing dense probe packing, controlled orientation, and minimized steric hindrance following attachment. This enables reproducible sensor fabrication and stable signal generation across electrochemical, optical, and impedance-based detection systems.
Recognition Mechanism
Target recognition is mediated by a sequence-engineered single-stranded DNA aptamer that undergoes conformational folding upon interaction with structural domains of the CRP pentamer. Binding occurs through a combination of electrostatic interactions, hydrogen bonding, and structural complementarity. The conformational transition upon CRP binding produces stable surface-associated complexes suitable for label-free detection and signal-transduction biosensor platforms.
The aptamer maintains structural integrity following immobilization and provides reversible yet stable binding kinetics suitable for quantitative sensing applications.
Specificity and Selectivity
The CRP BiosensorProbe™ demonstrates high molecular specificity toward C-Reactive Protein through sequence-driven structural recognition. The aptamer is designed to minimize cross-reactivity with abundant serum proteins such as albumin, immunoglobulins, and related inflammatory markers. The binding interaction targets conformational epitopes unique to CRP, enabling selective detection in complex biological matrices including serum, plasma, and buffered samples.
High selectivity supports reliable detection in multiplex biosensor configurations and reduces background signal from non-specific adsorption.
Molecular Format and Functionalization
The product consists of a synthetic single-stranded DNA aptamer containing a terminal thiol (–SH) functional group introduced through controlled chemical modification. The thiol group enables chemisorption onto gold surfaces and covalent coupling with thiol-reactive coatings through metal–sulfur bonding or maleimide–thiol reactions.
The probe is purified to high chemical purity and stabilized to preserve functional group reactivity, structural folding, and target-binding performance.
Surface Immobilization Chemistry
The terminal thiol group supports direct immobilization on gold electrodes through formation of self-assembled monolayers. The probe is compatible with nanostructured gold, planar gold electrodes, gold nanoparticles, and thiol-reactive polymer coatings.
Surface attachment enables controlled probe orientation, improved target accessibility, reduced probe desorption, and reproducible surface coverage. Immobilized probes maintain activity under standard biosensor operating conditions and repeated assay cycles.
Compatible Sensor Surfaces
Gold electrodes and nanostructured gold substrates
Gold nanoparticle-modified interfaces
Thiol-reactive polymer coatings
Maleimide-functionalized surfaces
Electrochemical impedance and amperometric sensors
Microfluidic lab-on-chip platforms
Surface plasmon resonance gold chips
Performance Characteristics
High specificity toward C-Reactive Protein
Low non-specific adsorption on sensor surfaces
Stable immobilization on gold substrates
Preserved aptamer folding after surface coupling
Reproducible binding performance in serum and buffer matrices
Suitable for label-free and signal-amplified detection systems
Stability
The CRP BiosensorProbe™ is chemically stabilized to maintain aptamer conformation and thiol reactivity under recommended storage and operating conditions. The DNA aptamer structure provides strong resistance to temperature variation, moderate pH changes, and repeated assay cycles following immobilization. Surface-bound probes demonstrate stable binding performance under physiological ionic strength and standard biosensor operating environments.
Functional group reactivity may gradually decrease upon exposure to oxidizing conditions; therefore, minimizing air exposure and maintaining appropriate storage conditions is recommended.
Storage
Store at −20°C in the supplied buffered formulation. Avoid repeated freeze–thaw cycles. Protect from prolonged exposure to light, heat, and oxidizing environments to preserve thiol functionality. Under recommended storage conditions, the product is stable for at least 12 months from the date of receipt.
Applications
Electrochemical biosensor development
Inflammation and infection biomarker detection
Cardiovascular risk monitoring research
Surface plasmon resonance assays
Microfluidic diagnostic device development
Wearable biomarker sensing platforms
Multiplex protein detection systems
