Toward an injectable continuous osmotic glucose sensor.
BACKGROUND
The growing pandemic of diabetes mellitus places a stringent social and economic burden on the society. A tight glycemic control circumvents the detrimental effects, but the prerogative is the development of new more effective tools capable of longterm tracking of blood glucose (BG) in vivo. Such discontinuous sensor technologies will benefit from an unprecedented marked potential as well as reducing the current life expectancy gap of eight years as part of a therapeutic regime.


METHODS
A sensor technology based on osmotic pressure incorporates a reversible competitive affinity assay performing glucose-specific recognition. An absolute change in particles generates a pressure that is proportional to the glucose concentration. An integrated pressure transducer and components developed from the silicon micro- and nanofabrication industry translate this pressure into BG data.


RESULTS
An in vitro model based on a 3.6 x 8.7 mm large pill-shaped implant is equipped with a nanoporous membrane holding 4-6 nm large pores. The affinity assay offers a dynamic range of 36-720 mg/dl with a resolution of +/-16 mg/dl. An integrated 1 x 1 mm(2) large control chip samples the sensor signals for data processing and transmission back to the reader at a total power consumption of 76 microW.


CONCLUSIONS
Current studies have demonstrated the design, layout, and performance of a prototype osmotic sensor in vitro using an affinity assay solution for up to four weeks. The small physical size conforms to an injectable device, forming the basis of a conceptual monitor that offers a tight glycemic control of BG.
Johannessen
Erik
E
Vestfold University College, Tønsberg, Norway. eaj@hive.no
Krushinitskaya
Olga
O
Sokolov
Andrey
A
Philipp
Häfliger
H
Hoogerwerf
Arno
A
Hinderling
Christian
C
Kautio
Kari
K
Lenkkeri
Jaakko
J
Strömmer
Esko
E
Kondratyev
Vasily
V
Tønnessen
Tor Inge
TI
Mollnes
Tom Eirik
TE
Jakobsen
Henrik
H
Zimmer
Even
E
Akselsen
Bengt
B
D000465:Algorithms; D000537:Aluminum Oxide; D001786:Blood Glucose / Q000032:analysis*; D015190:Blood Glucose Self-Monitoring / Q000295:instrumentation*; D003920:Diabetes Mellitus / Q000097:blood*; D001330:Electronic Data Processing; D006801:Humans; D007202:Indicators and Reagents; D008567:Membranes, Artificial; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D036103:Nanotechnology; D009995:Osmosis; D019736:Prostheses and Implants; D015203:Reproducibility of Results; D014462:Ultrafiltration
D001786:Blood Glucose; D007202:Indicators and Reagents; D008567:Membranes, Artificial; D000537:Aluminum Oxide