biosensor microelectrodes guido drago applied enzyme technology ltd
TRANSCRIPT
Company History
• Applied Enzyme Technology Ltd formed in 1994
• Smart Awards 1994 & 1995 protein stabilisation technology
• Patents for dry stabilisation fully granted in 1995 and 1996
• Patent for solution stabilisation fully granted in 2000
• AET acquired by LRH Ltd. and relocated June 2001
• BIOWISE Demonstrator Award 2003
• SIF Award 2009
• Multiple EU, TSB, Home Office & DEFRA Grants
• Contract research for the stabilisation of specific proteins
• Supply Protein Stabilisation Kits for stability troubleshooting
• Supply of bulk stabiliser formulations
• Supply pre-stabilised enzymes
• Design and develop biosensors
• Carry out prototype & contract manufacture of low volume sensors
• Production of our own environmental & agrifood sensors
Products & Services
TSB SENSACELL-TOX PROJECT TASKS
• Stabilise GOX and LOX in a water based carbon ink
• Print microelectrode structures < 500 Micron
• Incorporate glucose and lactate biosensors on the final chip
Gluconolactone
e-
Co+
Co2+ ½H2O2
½O2 + H+
½ Glucose
O2,GOD
+ 0.5 V
Immobilised GOD
SPCEbody
Schematic of Oxidase Biosensor
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t / s
Cur
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y = 1172 x - 6.79
R2 = 0.9997
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Cur
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/ nA
Amperogram obtained using glucose biosensors in stirred solution. Arrows correspond to 70 µl additions of 50 mM glucose to 10 ml supporting electrolyte.
Water Based GOX Ink
Glucose calibrations carried out on GOX/carbon ink stored for up to 215 days at room temperature
GOX Ink Stability
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Time after printing / days
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res
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glu
cose
/ nA
Electrode Stability
Water based GOX electrodes printed and stored at 4oC.Electrodes tested using 2mM glucose additions
Lactate Biosensor
Fig.5. (A) amperogram and (B) calibration plot for L-lactate in culture medium using a microband biosensor at 37oC.
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)
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Cell Measurements
Glucose Lactate
Stencil Printing
Electroformed aperturesPositive advantage since no threads to reduce open area.
Stencils provided by Tecan Ltd.
Results from HIPER-ACT EU Project
Stencil Printing
X10 Mag X60 Mag X 200 Mag
Measured Line Widths (µm) 35 41 39 36 39 30 47 47 Ave 39
Vertical print stroke 20 micron stencil
•Stabilised GOX in the carbon ink for 215 days at room temperature
•Stabilised the LOX in carbon ink for 28 days at room temperature
•Successfully proved that the electrode performance was not effected •by gamma irradiation sterilisation technique
•Successfully printed structures < 500micron square •onto final device chips
•Final devices tested on cell media
Conclusions
Applied Enzyme Technology Ltd.
Monmouth HouseMamhilad ParkPontypool NP4 OHZ
Tel: 01495 751 100Fax: 0870 052 8250Email: [email protected]: www.gwent.org