Download (size, shape, surface charge, roughness and

A Fundamental Study of Nanoparticle–Protein
Mutual Interactions:
Role of Nanoparticle Morphology and Size
Funded by the NSF Grant number: #0925232
G. Pyrgiotakis1, I. Chernyshova2, P. Sharma1, A. Singh1,
S. Ponnurangam2, B. Moudgil1 and P. Somasundaran2
1University
of Florida, 2 Columbia University
Center for Particulate & Surfactant Systems (CPaSS)
IAB Meeting
New York, NY
August 20th 2009
Industrial Relevance
• Nanoparticles used in many different industrial processes
 CMP process, catalysis, etc
• Wide range of nanoparticle-based
products:
 Energy (e.g. high capacity batteries)
 Optical (e.g. antireflective coatings)
 Micro/nano-electronics
(e.g. capacitors, displays)
 Pharmaceuticals (e.g. drug delivery)
 Biomedical (e.g. bioimaging)
Disposal and environmental fate?
Potential toxicity & Interactions with living cells
• Particles in physiological fluids interact initially with the proteins
• The adsorbed proteins (soft and hard corona) dictate the fate of the
particles and can alter their properties
Lynch, I., Dawson, K.A. Protein-nanoparticle interactions, Nano Today, 2008, 3, 40-47.
Hypothesis
Mutual Interactions:
The localized features
of the particles can
influence the
protein adsorption and
the adsorption can affect
the particle proteins
1. The protein conformation depends on the various particle surface
properties.
Size, shape, surface charge, roughness and porosity
2. The adsorbed proteins are affecting the particle properties.
Dissolution, electronic properties.
Objective
Investigate:
1. The effect of surface properties (size, shape, surface charge,
roughness and porosity) on protein adsorption
2. How the protein adsorption affects the particle properties.
Approach
• Spectroscopy & computer simulation technique to understand
fundamentals of protein adsorption and conformation of adsorbed
proteins.
• Research focus – localized features
of the surface as opposed to the
average measured values.
• Simulate the nanoparticle features
on a flat surface to measure the
localized effects using AFM
Proposed Substrate – Protein System
500 nm
100 nm
Silica Nanoparticles
• Widely used for biomedical
applications
• Ease of synthesis of different
morphology silica particles.
Human
Serum
Albumin
Hematite Nanoparticles
• Major component of
cosmetics formulations
• Ease of synthesis with wide
range of sizes and shapes.
• In physiological environments a variety of proteins adsorb on the particles.
• Proof-of-concept studies will be conducted with albumin.
 Well studied and documented under different conditions.
Size
Novelty of the Approach
Mesoporous and
Nanolithographic surfaces
Mesoporous Silica
50 nm
50 nm
Porosity
2 µm
• Porous and non-porous particles.
• Traditional methods for simulating
• Simultaneous examination of all the
roughness (ion beam, chemical
parameters (size and pores).
etching) yield non-uniform features
• Use pores to simulate the roughness.
at nanoscale scales.
• Sol-Gel chemistry allows for
• Nanolithography has better control
variation in the pore size and particle
of the nanoscale features.
size.
Deliverables
Year-End Deliverables
• Develop the protocols and optimize the procedures to investigate
protein-substrate interactions at localized features level.
• Gather proof-of-concept data for a systematic and comprehensive
study.
Long Term Deliverables
• Derive scaling laws correlating the protein adsorption and the
surface features.
• Develop methodologies to include other organic molecules such
surfactants and more relevant proteins.
Timeline
Q1
Q2
Q3
Q4
Protein
Conform.
Particle/surface synthesis
Mesoporous
Nanolithography
AFM, XPS, Zeta Potential
AFM for localized features
Size, pores var.
Particle Characterization
Hematite particles synthesis
Hematite particle Character.
QCM
Quantum chemistry modeling
Protein
Proteins on surface
Proteins
in
solution
Packing
Proteins on particles
On mesoporous surfaces Raman, FTIR, NMR etc
On silica particles Raman, FTIR, NMR etc
On hematite particles Raman, FTIR, NMR etc
Est. correlations
Acknowledgements:
NSF grant #: 0925232
CPaSS, CPaSS members
Columbia U.
U of Florida