1. Marie Curie Research Training Network
Studies on cellular response to targeted single ions using nanotechnology
CELLION
Dr. Mary Farrell
Department of Engineering Sciences
The Ångström Laboratory
Uppsala, Sweden

2. Electroanalysis in the Nanodomain : Quinone Monolayers and
Sept April 2003
Electroanalysis in the Nanodomain :
Quinone Monolayers and
Nanometer Dimensioned Electrodes
Reduction
Oxidation
(A)
Quartz Capillary
Platinum Wire
(B)

3. July 2003 – June 2004 INTERCALNET
The development of lithium intercalation materials and techniques for their characterisation - +
ITO
ITO
Conduttore ionico
Film elettrocromico
Materiale a intercalazione

4. Studies on cellular response to targeted single ions
using nanotechnology
AIM : To fabricate a nanoelectrode array sensor using ion track technology for the detection of oxygen / nitric oxides
Materials used : Polyimide foils – 75 mm
Espandex – 50mm
Processes / Techniques
Wet / Dry etching
Lithography
Electroplating
SEM
Electrochemical characterisation

5. Oxygen Sensing Clark type oxygen electrode
Clark, L.C., Trans Am Soc Artif Intern Organs, 1956, 2, 41
Reduction of potential 400 – 1200 mV
2e- + ½ O2 + H2O OH-
Current proportional to gas concentration
Application areas : biosensor development, clinical diagnostics, fermentation control, water and gas analysis and industrial aplications.
Much research effort is devoted to the miniturisation of the traditional Clark type cell for many biological and biochemical applications.

6. Process Steps – Polyimide
Irradiation of Polyimide - 75mm
Ion track density : 1x x107/cm2
PI 75mm
Mask 25mm
High energy 129Xe27+
One sided Lithography
Cu ~ 200 nm
Resist
Positive Resist : S1813
Spin speed : 1000 rpm, 8sec; 3000 rpm, 40 sec
Softbake : Hotplate deg C, 3 mins
Exposure : 17sec – Carl Suss mask aligner MA6/BA6
Development : 40 sec in 1% NaOH solution
Hardbake : 115 deg C, 20 mins
Dry etch PI (~ 10mm) in aperatures
Wet etch pores
Sodium hypochloridte (NaOCl), Boric Acid (H3BO3)
Etch temperature : 60 deg C
Preheating time of solution : 1hour
Etch time : varies depending on pH

7. Process Steps – Polyimide
Evaporate Cu on frontside, electroplate Ni
Create backside electrode (Ni or Cu)
Etch frontside Cu
Nanode Sensing side
Cu Etching : 320g sodium persulfate Na2(SO4)2 per litre of water
Ni electroplating : NiSO4 x 6H2O M
Boric Acid (H3BO3) – 0.65 M
Applied potential : V vs Ag/AgCl, Platinum counter
Deposition Time : varied
Characterise Ni nanode sensing side in SEM
Electrochemical characterisation of Ni nanodes
Samples sputtered with gold before SEM analysis
EC Characterisation : 0.1 M NaOH
Cyclic voltammetry: Potential limits -0.5 to +0.7 V vs Ag/AgCl, platinum counter

8. Electrochemical Characterisation of Nickel
Giovanelli, D., Lawrence, N.S., Li Jiang, Jones, T.G.J., Compton, R.G., Sensors and Actuators B, 2003, 88, 320

9. Pore Etching Study - Polyimide
Etch Time / s
Solution pH
Pore Diameter / nm 50
9.84
195.72 60
9.82
273.98 75
9.77
322.05 90
9.75
402.54
105
9.73
429.19
120
9.71
485.77
120 minutes etching

10. Espandex Irradiation of Espandex Cu-PI-Cu : 5-50-5mm
Ion track density : 1x x107/cm2
Cu ~ 5mm
Nanode Sensing side

11. SEM Characterisation - Espandex

12. Future Work Acknowledgements
Continue work with Polyimide
Use single ion tracks to make nanoelectrodes instead of arrays
Electrodeposit Au / Pt in pores
Characterise using SEM/Olympus microscope, XPS.....
Work on the cell for EC measurements - oxygen detection
Acknowledgements
Prof. Klas Hjort
Members of the group : Mikael Lindeberg
Hanna Yousef
Marek Skupinski
Gunjana Sharma
Marcus Lehto
Roger Boden

13. Thank you for your attention!
Questions / Comments?