Download presentation
Presentation is loading. Please wait.
Published byLaura Owen Modified over 9 years ago
1
20 Jan 03 i-STAT Microanalytical Systems for Point-of- Care Blood Diagnostics Eric Brouwer, R&D Scientist ebrouwer@istat.ca i-STAT Canada Ltd www.istat.com
2
20 Jan 03 i-STAT Outline Point-of-care diagnostics i-STAT cartridge - fluidics i-STAT cartridge – sensors Sensor processing Economics of POC Reference: Lauks, I.R. Acc. Chem. Res. 1998, 31, 317-324
3
20 Jan 03 i-STAT Point of Care (POC) Blood Diagnostics VS
4
20 Jan 03 i-STAT A good POC should be foolproof no user intervention should be required to maintain the sensors perform calibration pre-treat the sample deliver the sample only good results should be reported user and system errors are detected
5
20 Jan 03 i-STAT i-STAT Cartridge
6
20 Jan 03 i-STAT Cartridge construction
7
20 Jan 03 i-STAT Fluidic control Sequence: 1.Calibrant 2.Air bubble 3.Blood
8
20 Jan 03 i-STAT Reagent mixing
9
20 Jan 03 i-STAT Temperature control
10
20 Jan 03 i-STAT Self-testing based on a potentiometric sensor wave form
11
20 Jan 03 i-STAT Point of Care Test Panel
12
20 Jan 03 i-STAT Electrolytes: Na, K, Cl, Ca, NH 4 + Metabolites: Glu, BUN, Creatinine, Lactate Hematology: Hct Blood gases: pH, p(CO 2 ), p(O 2 ) Coagulation: PT, ACT, aPTT Cardiac Marker: Troponin-I i-STAT sensors
13
20 Jan 03 i-STAT Definitions Transducer (L. transducere: to translate, to transfer) –a device that ‘translates’ a form of energy into another form of energy Sensor –a transducer that transforms any form of energy into an electrical signal Biosensor –a sensor that makes use of a biological material for its sensing function
14
20 Jan 03 i-STAT Sensor Classification based on the energy to be measured –physical (mass, pressure, temperature, flow, distance, position, speed….) –chemical (ions selective sensors, gases, glucose, urea….) based on the construction principle –piezo sensors (piezo-electric, piezo-resistive, surface acoustic wave) –capacitive sensors –electrochemical sensors (pH, ions, glucose, oxygen….) –thermal sensors (thermistors, diodes....) –optical (colorimetric, fluorescent….) based on the application –immunosensors –gas sensors –ion sensors
15
20 Jan 03 i-STAT i-STAT sensors use planar microtechnology specific electronic technology surface processing of a semiconducting substrate (Si/SiO 2 ) largely relying on the photolithographic patterning allows –a high miniaturization –a high reproducibility is well established for mass-production the higher the production the lower the cost per sensor it opens the way toward the ‘intelligent’ or ‘smart’ sensors
16
20 Jan 03 i-STAT Blood gases sensors 0.8 m gelatin 1.1 m polyimide 0.1 m gold m silicone polycarbonate silicon 1 m SiO2 0.03 m titanium tungsten 32 m PVC membrane 1.1 m polyimide 0.03 m titanium tungsten silicon 1 m SiO2 1. m dimethyl polysiloxane 2 m sucrose, NaHCO 3 0.1 m gold Blood Gas Panel 0.8 m AgCl 0.66 m silver
17
20 Jan 03 i-STAT Thin film processing SiO2 Platinum electrode Enzyme Layer & H 2 O 2 selective membrane Cap layer Glucose Anode Diffusion Barrier
18
20 Jan 03 i-STAT Thin Film Processing: Photolithography 1. substrate 2. metal deposition 7. photoresist removal 3. photoresist spinning 4. photoresist (+) exposure (through a mask in UV light) 5. photoresist development 6. metal etching substrate photoresist metal mask
19
20 Jan 03 i-STAT Thin Film Processing: Lift Off 1. substrate 3. photoresist (+) exposure (through a mask in UV light) 4. photoresist development substrate photoresist metal mask 2. photoresist spinning 5. metal deposition - sputtering, evaporation 6. photoresist removal
20
20 Jan 03 i-STAT Thick film processing Partial Drop Dispensing
21
20 Jan 03 i-STAT On-line visual inspection …
22
20 Jan 03 i-STAT … and final visual inspection
23
20 Jan 03 i-STAT Correlation with standard tests pO2pO2 p CO 2 pH
24
20 Jan 03 i-STAT
25
20 Jan 03 i-STAT Is all this cost effective? Hospital Lab: Total Cost $10.00 POC: Total Cost $6.70 Consolidated Lab: Total Cost $4.00 1999 analysis
26
20 Jan 03 i-STAT Conclusions Since 1992, i-STAT has provided a POC system which: features an autonomous, hand-held blood analyzer uses dry-stored, disposable cartridges with sensors built on Si detects errors and calibrates itself requires 0.1 mL whole blood provides results in 2 minutes accuracy and the precision comparable with any other tool on the market Over 25,000 hand-held analyzers in hospitals around the world 16 million cartridges annually, with >20% annual growth rate Impact on health care: faster surgery, diagnostics, real-time monitoring
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.