Glucose measurements with sensors and ultrasound.
Accurate monitoring of the blood glucose level in diabetics is essential in preventing complications. Generally, conventional over-the-counter glucose meters require frequent painful finger punctures to obtain samples, which makes a noninvasive method preferable. The purpose of this study was to demonstrate that glucose levels can be measured transdermally with the combination of the low-profile cymbal array and an electrochemical glucose sensor consisting of amperometric electrodes and a novel glucose oxidase hydrogel. Interstitial fluid glucose concentrations can be determined with the electrochemical glucose sensor after the skin is made permeable to glucose by ultrasound (US) (20 kHz) with the thin (< 7 mm) and light (< 22 g) cymbal array. Using this array to deliver insulin into hyperglycemic rats, our previous experiments demonstrated that blood glucose levels would decrease 233.3 mg/dl with 5 min of US exposure. With the sensor and array, our goal was to determine the glucose levels of hyperglycemic rats noninvasively and evaluate the possible bioeffects. A total of 12 anesthetized rats were placed into two groups (US exposure group and control group) and the array (I(SPTP) = 100 mW/cm(2)) with a saline reservoir operating for 20 min was affixed to the abdomen. The array was removed and an electrochemical glucose sensor was placed on the exposed area to determine the glucose concentrations through the skin. Comparison was made using a commercial glucose meter with the blood collected from a jugular vein. The average blood glucose level determined by the sensor was 356.0 +/- 116.6 mg/dl, and the glucose level measured by the commercial glucose meter was 424.8 +/- 59.1 mg/dl. These results supported the use of this novel system consisting of the electrochemical glucose sensor and the cymbal array for glucose monitoring.
Department of Bioengineering, College of Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
Seungjun
S
Lee
Vivekanand
V
Nayak
Jeff
J
Dodds
Michael
M
Pishko
Nadine Barrie
NB
Smith
D000818:Animals; D015374:Biosensing Techniques; D001786:Blood Glucose / Q000032:analysis; D015190:Blood Glucose Self-Monitoring / Q000295:instrumentation / Q000379:methods*; D005240:Feasibility Studies; D005949:Glucose Oxidase; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D006943:Hyperglycemia / Q000097:blood / Q000175:diagnosis*; D010539:Permeability; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000473:pathology; D014159:Transducers; D014465:Ultrasonics
D001786:Blood Glucose; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D005949:Glucose Oxidase