Miniaturized one-chip electrochemical sensing device integrated with a dialysis membrane and double thin-layer flow channels for measuring blood samples

• Published in: Biosensors & bioelectronics 2006-02, Vol.21 (8), p.1649-1653
• Main Authors: Kurita, Ryoji, Yabumoto, Norikuni, Niwa, Osamu
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Biosensor; Biosensors; Biotechnology; Blood Chemical Analysis - instrumentation; Blood Chemical Analysis - methods; Dialysis; Dialysis - instrumentation; Dialysis - methods; Dogs; Electrochemical; Electrochemistry - instrumentation; Electrochemistry - methods; Enzymes, Immobilized - chemistry; Equipment Design; Equipment Failure Analysis; Flow Injection Analysis - instrumentation; Flow Injection Analysis - methods; Fundamental and applied biological sciences. Psychology; Lactate; Lactic Acid - blood; Membranes, Artificial; Methods. Procedures. Technologies; Microdevice; Microfluidic Analytical Techniques - instrumentation; Microfluidic Analytical Techniques - methods; Microfluidics; Mixed Function Oxygenases - chemistry; Systems Integration; Various methods and equipments
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2005.07.016

We have developed a microfluidic device consisting of a gold film working electrode modified with lactate oxidase and Os-poly(vinylpyridine) mediator containing horseradish peroxide, and reference and counter electrodes in a microflow detection channel separated by a microdialysis membrane from another microflow channel used for sample injection. The dialysis membrane is cellulose with a molecular weight cut off of 10 kDa. We achieved control over a wide recovery rate range of 3–94% because the device is capable of controlling both flow rates in the dual thin-layer channels. We were able to measure the lactate concentration in blood samples within a few minutes without any pretreatment because biomolecules are simultaneously separated by molecular weight and detected in the device. We achieved quantitative and reproducible measurements of the lactate concentration in blood samples, and obtained a relative standard deviation of 1.5% ( n = 8). With our device, the lactate concentration in dog whole blood was measured with high stability without any pretreatment.