Product Description
The BioDeviceLab 20 nm Endotoxin-Free Gold Nanoparticles are precision-engineered colloidal gold particles designed for biologically sensitive and analytically demanding applications. At ~20 nm diameter, these nanoparticles exhibit a pronounced localized surface plasmon resonance (LSPR) with enhanced absorbance and scattering compared to smaller particles, enabling robust UV–Vis detection, colorimetric assay development, and plasmonic sensing.
These nanoparticles are synthesized using controlled protocols and subjected to endotoxin-reduction processes to minimize lipopolysaccharide (LPS) contamination. The particles are stabilized with citrate/tannic acid ligands in an aqueous formulation, providing excellent colloidal stability and compatibility with biological samples, microfluidic platforms, and lab-on-chip systems.
The characteristic SPR absorbance peak near 520–525 nm enables reliable optical characterization and quality control. The 20 nm size provides an effective balance between optical signal strength and surface area, supporting efficient passive adsorption of proteins, antibodies, and ligands while reducing unintended immune activation in endotoxin-sensitive assays.
Intended Use
This product is intended for research applications including:
• Endotoxin-sensitive biosensor development
• Cell-based assays and live-cell imaging
• Immune signaling and cytokine response studies
• Passive conjugation of proteins, antibodies, and ligands
• Optical and plasmonic signal amplification
• Microfluidic and lab-on-chip integration
Principle of Operation
Gold nanoparticles exhibit localized surface plasmon resonance (LSPR), where collective oscillation of surface electrons occurs in response to incident light.
• The SPR peak position and intensity depend on particle size and surrounding environment.
• Biomolecule binding or changes in local refractive index alter optical signals, enabling sensing.
• The 20 nm size enhances absorbance and scattering while maintaining high surface accessibility.
• Endotoxin-free formulation minimizes background immune activation in sensitive biological systems.
Calibration & Optical Characterization
• Optical density (OD) is defined at the SPR peak wavelength using a 1 cm pathlength.
• UV–Vis spectroscopy verifies the characteristic absorbance peak (~520–525 nm).
• Particle concentration and molar extinction coefficients are calculated at OD = 1.
• Dynamic Light Scattering (DLS) confirms hydrodynamic size and narrow dispersity.
• Endotoxin levels are assessed using standard assays (e.g., LAL) to verify low LPS content.
Analytical & Physical Characteristics
Nominal particle diameter: ~20 nm
Peak SPR wavelength: ~520–525 nm
Particle concentration: ~1.1 × 10¹³ particles/mL
Weight concentration: ~5.2 × 10⁻¹ mg/mL
Molar extinction coefficient: ~4.0 × 10⁷ M⁻¹·cm⁻¹
Size dispersity: <15%
Surface area per particle: ~1.26 × 10³ nm²
Surface-to-volume ratio: ~0.3
Particle mass: ~3.6 × 10⁻¹⁶ g
Molar mass: ~5.4 × 10⁷ g/mol
Molar concentration: ~2.0 × 10⁻⁹ M
Supplied volume: 500 mL
Endotoxin level: Certified low endotoxin (specification available on request)
Selectivity & Compatibility
Gold nanoparticles are chemically inert and broadly compatible with biological molecules and assay platforms. Endotoxin-free preparation minimizes unintended immune activation, making these nanoparticles suitable for sensitive cell-based, immunological, and host–microenvironment studies.
Package Contents
Each unit contains:
• 500 mL of 20 nm endotoxin-free citrate-stabilized gold nanoparticle colloidal suspension
• Optical characterization documentation
• Endotoxin quality assurance report
Required Materials
• UV–Vis spectrophotometer
• Dynamic Light Scattering (DLS) instrument (recommended)
• Endotoxin-free laboratory consumables
• Buffers compatible with biological workflows
Sample Handling & Use
• Gently swirl before use to ensure uniform suspension.
• Avoid vigorous shaking or sonication that may induce aggregation.
• Use endotoxin-free pipette tips and containers for sensitive assays.
• Dilute with compatible aqueous buffers as needed.
Quality Control
• Each production lot is verified for SPR peak position, particle concentration, size distribution, and endotoxin level.
• Batch-to-batch consistency supports reproducibility in sensitive biological workflows.
• Optical, physical, and endotoxin metrics follow standardized QC practices.
Storage & Stability
• Store at 4–25 °C.
• Do not freeze.
• Protect from prolonged exposure to direct light.
• When stored properly, the colloid maintains stability and optical performance throughout its shelf life.
Limitations
• For research use only.
• Not intended for diagnostic or therapeutic use.
• Performance may vary depending on buffer composition and downstream functionalization strategy.
Applications
• Endotoxin-sensitive biosensor development
• Cell culture and immune activation studies
• Host–microbiome and inflammatory signaling models
• Protein and antibody conjugate engineering
• Microfluidic and lab-on-chip systems
• Biodevice calibration and benchmarking
