Post on 03-Aug-2015
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Sensing the Swell
Aoife Morrin Dublin City University
Responsive materials
Formats amenable to
electrochemical control and sensing
Tissue Hydration Skin
Patch
Gas Sensor Skin Tattoo
Protein Mining in Skin ISF
• Non-invasive• Early detection of
eczema flare-ups
• Non-invasive• Detection of acetone
as a marker for occult liver pathology
• Minimally-invasive• Melanoma biomarker
extraction from ISF
Conformable, conducting materials for skin electronics
Conformable, responsive materials for skin gas sensing
Smart nanomaterials for protein capture in
skin
Gorey, B., Smyth, M.R., White, B., Morrin, A. (2014). Journal of Materials Chemistry C, 2(30):6004-6009.
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Semi-wet and typically inert – host-network Ability to control diffusional behaviour of
molecules Responsive swelling
Hydrogels
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Responsive swelling
pH responsive hydrogel O
OO
O
NH2
OO
NH2+
O
OO
OH
NHO
ONH
OH
OO
O
PEGDGE Jeffamine EDR 148
Epoxy-amine network
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Conformable electrode substrate
Bare
1 coating
2 coatings
Tracking biospecific swelling using impedance
Z' /ohm
0 2000 4000 6000 8000 10000 12000 14000 16000 18000
- Z
'' / o
hm
0
5000
10000
15000
20000
25000
30000
35000
Water 1 uM glucose5 uM glucose10 uM glucose50 uM glucose100 uM glucose1 mM glucose3 mM glucose4 mM glucose 6 mM glucose10 mM glucose
1 mM glucose
10 mM glucose
….at least a 1000-fold improvement in LOD
MacKenna, N., Calvert, P., Morrin, A. (2015). Analyst. DOI: 10.1039/C4AN02252A
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MO
rGO
MO
Controlled release – electro-stimulation
MacKenna, N., Calvert, P., Morrin, A., Wallace, G.G., Moulton, S. (2015). J. Mater. Chem. B, 3:2530-2537.
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Time (min)
0 100 200 300 400
Sw
elli
ng
Rat
io
0
5
10
15
20
Increasing [acid]
Low pH(~ pH 3-
4)
O
OO
OH
NHO
ONH
OH
OO
O
High pH
Controlled release – pH-stimulation
Response times
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Disk Thick film
Not radically improved
Superporous
Aim to completely eliminate diffusional barrier
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Inducing superporosity Limitation on polymerisation using CO2 gas generation Oxygen gas generation via hydrogen peroxide catalysis
on Ag NPs
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Superporous hydrogels
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Response Times
Bulk Gel200-500 min
Superporous Gel20-40 s
Following On…..
Tissue Hydration Skin
Patch
Gas Sensor Skin Tattoo
Protein Mining in Skin ISF
• Non-invasive• Early detection of
eczema flare-ups
• Non-invasive• Detection of acetone
as a marker for occult liver pathology
• Minimally-invasive• Melanoma biomarker
extraction from ISF
Conformable, conducting materials for skin electronics
Conformable, responsive materials for skin gas sensing
Smart nanomaterials for protein capture in
skin
Thanks!To my group and my collaborators:
Esp: Nicky MacKenna Prof. Paul Calvert Prof. Simon Moulton Prof. Gordon Wallace
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aoife.morrin@dcu.ie