Liquid nanodispensing : molecules deposition and manipulation of ultrasmall droplets
CIC nanoGUNE Seminars
- Speaker
-
Thierry Ondarçuhu. Nanosciences group, CEMES-CNRS, Toulouse, France
- When
-
2010/06/17
14:00 - Place
- nanoGUNE seminar room, Tolosa Hiribidea 76, Donostia - San Sebastian
- Add to calendar
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Controlled deposition of individual molecules on a surface is an important
challenge in many studies in nanosciences. We present an AFM-based method for
dispensing and manipulation of liquid nanodroplets on a surface. This newly
developed nanoscale dispensing system (NADIS) is based on the direct transfer
of liquid from a hollow AFM tip through a small aperture at its apex to the
substrate by simple contact [1]. With an ink supplied from an on-tip
reservoir, we can transport droplets onto a substrate in the femtoliter to
attoliter range with a high droplets density. We explored the liquid transfer
mechanism from the tip to the substrate and showed that the size of dispensed
droplets can be accurately and reproductively controlled by parameters such as
the aperture size on the probe, the surface energy of both the tip outer wall
and the sample surface [2]. By scaling down this method, we were able to
deposit arrays of droplets with a diameter as small as 70 nm, which for
standard dilutions contains only few molecules. Direct patterning of proteins
or nanoparticles demonstrated the versatility of the method. An original
deposition set-up including two AFM tips was also developed [3] in order to
position the droplets on predefined structures on the surface, a crucial point
for many applications.
Due the small dimensions of the manipulated droplets, NADIS is also a unique
technique to study wetting and capillarity at nanometer scale [4,5], a
question which remains largely unanswered.
References:
[1] A.Meister, M. Liley, J. Brugger, R. Pugin, H. Heinzelmann, Appl. Phys.
Lett. 85 (2004) 6260.
[2] A.Fang, E. Dujardin, T.Ondarçuhu, NanoLett. 6 (2006) 2368.
[3] T. Ondarçuhu, L. Nicu, S. Cholet, C. Bergaud, S. Gerdes, C. Joachim, Rev.
Sci. Instr. 71 (2000) 2087-2093.
[4] J. Arcamone, E. Dujardin, G. Rius, F. Pérez-Murano, T. Ondarçuhu,
J.Phys.Chem.B 111 (2007) 13020.
[5] L. Fabié, H. Durou, T. Ondarçuhu, Langmuir, 26 (2010) 1870