(4co) Interfacial Forces in Nanoparticle and Biological Systems at the Micro- and Nano-Scales

The overall theme of my research is to understand the
molecular and nanoparticle behavior at the interface of surfaces. As the size
of particles reaches characteristic length scales, novel physical properties
(compare to bulk properties) start to emerge [1]. The carbon nanotubes are one
candidate and I will present a study of aqueous film of carbon nanotubes on
mica surfaces and in particular its frictional properties.

Another interesting interfacial system is bio-membrane. We
have focused on the myelin membrane. The myelin sheath is a multilamellar
membrane surrounding the axon of neurons in the nervous system. This sheath
acts as an electrical insulator, which allows for faster and more efficient
conduction of nerve impulses than unmyelinated nerves. Myelin dysfunctions vary
from deterioration of signal transduction to demyelinating diseases such as
multiple sclerosis (MS). We want to understand the molecular synergistic
interaction responsible for a healthy myelin membrane structure. Using a
Surface Forces Apparatus we have studied the interaction forces and adhesion
between supported myelin lipid bilayers mediated by myelin basic protein [2].

In the last part of this poster I want to present the
development and implementation of new devices [3] for interfacial science and
how to integrate them into a Surface Forces Apparatus (SFA) [4]. An
electrochemical cell developed for the SFA for monitoring the thickness change
of silica surfaces in a silica-mica system due to silica dissolution under
influence of electrochemical potential will be shown [5].

[1]        Min Y J, Akbulut M, Kristiansen K, Golan Y, and
Israelachvili J; ?The role of interparticle and external forces in nanoparticle
assembly?. Nature Materials 7 (2008) 527-538.

[2]        Min
Y, Kristiansen K, Boggs J M, Husted C, Zasadzinski J A, and Israelachvili J;
?Interaction forces and adhesion of supported myelin lipid bilayers modulated
by myelin basic protein?. Proceeding of the National Academy of Science 106
(2009) 3156-3159.

[3]        Kristiansen
K, McGuiggan P M, Carver G, Meinhart C, and Israelachvili J; ?3D Force and
Displacement Sensor for AFM and SFA measurements?. Langmuir 24 (2008)
1541-1549.

[4]        Israelachvili
J, Min Y, Akbulut M, Alig A, Carver G, Greene G W, Kristiansen K, Meyer E E, Pesika
N, Rosenberg K, and Zeng H; ?Recent advances in the surface forces apparatus
(SFA) technique?. Reports on Progress in Physics 73 (2010) 036601.

[5]        Kristiansen
K, Greene G W, Valtiner M, Boles J, and Israelachvili; ?Electrochemical
interpretation of silica dissolution processes?. Talk scheduled for AIChE
annual meeting 2010 in session: 01C19 ?Interfacial aspects in electrochemical
systems?.