Nanoparticles-Environment_Webinar Presentation.pdf

Analyzing Nanoparticle/Surface Interactions in the Environment Stephen Hussey, Ph.D. Biolin Scientific Inc. th Page 1 November 15 , 2012 Presentation Outline ? Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D) Technology A li ti S? pp ca on ummary ? Specific Application Examples ? Summary Page 2 Summary of Technology/Applications ? QCM-D Technology: ? Real time, label free technique for analyzing interactions/reactions occurring at surfaces ? Measures mass changes ? Measures rigidity/softness changes Page 3 Principles of the QCM-D Technology Quartz Gold Electrode Crystal Quartz Crystal – Piezoelectric material diam. 14mm 5MHz Gold Electrode - A voltage applied to a quartz crystal causes the crystal to oscillate at a specific frequency Page 4 Principles of the QCM-D Technology ? Apply voltage, cause the crystal to oscillate ? Stop voltage, allow crystal to come to rest ? Change in mass on sensor → change in frequency (?f) ? Change in viscoelastic properties → change in Dissipation (?D) Page 5 Principles of the QCM-D Technology Rigid Film Soft Film Input: Δf1 Real-Time Output: δ: thickness (m) / mass (ng) Voigt ModelΔf3 ΔD1 ΔD3 ρ: density (kg/m3) η: viscosity (G’’/ω), (kg/ms) μ: elasticity (G’), (Pa) Page 6 QCM-D Measurement Details 5 MHz 15 MHz 25 MHz 35 MHz 45 MHz, etc… Find Resonance Record Decay Communicate Data - Process is repeated as fast as 200 times per second Multiple overtones of both ?f and ?D enables viscoelastic modeling Page 7 - Application Areas Interactions Molecule-molecule and molecule-surface ? Nanoparticle-surface interactions ? Cell/Bacteria surface interactions- ? Protein adsorption or fouling ? Biomolecular interactions Reactions or Structural Changes ? Aggregation ? Film swelling or hydration H2O ? Crosslinking ? Degradation/Dissolution kinetics Bulk Characterisation ? Viscoelastic properties of fluids (protein Page 8 solutions, particles, surfactants etc...) Nanoparticle Applications Electronic