~Possible use in monitoring of blood-drug levels during open-heart surgeries~

Prof. Yasuo Yoshimi (Department of Applied Chemistry) developed a heparin sensor which has high sensitivity and reproducibility even in whole blood by using molecularly imprinted polymer and carbon paste electrode.
Heparin is a representative anticoagulant drug, which is especially necessary for open-heart surgeries using a heart-lung machine. The monitoring of the effects of the anticoagulant is an important factor for the outcomes of such surgeries. Conventionally, the anticoagulation effect was monitored by measurement of activated clotting time but it does not necessarily indicate overdose or underdose of the heparin. Prof. Yoshimi developed a sensor which directly detects the concentration of heparin in the blood stream.


1. More durable than conventional biosensors
2. Cost-efficient and shorter time required for manufacturing
3. Can respond in 30 seconds; is suitable for real-time monitoring

Conventional method

Prof. Yoshimi has been developing the heparin sensor using molecularly imprinted polymer grafted on an electrode by radical polymerization. Conventionally, the polymer was grafted by photo-irradiation on a flat electrode soaked in prepolymer solution. However, it is difficult to coat the electrode with molecular film evenly and thus resulting in the electrodes with large variability in their sensitivity to heparin. The variability has made it difficult to develop single-use sensor which is necessary for hygienic reasons.

New method

In the new method, the polymer is grafted on fluidized carbon particles (around 10 µm in diameter) by photo-irradiation. Highly homogenous electrode can be obtained by the sufficient mixing with the polymer-grafted carbon. The produced electrodes exhibit identical sensitivity levels in the blood specimens and promosing as disposable heparin sensors. The sensor responds within 30 seconds and is feasible for real-time monitoring.

Future outlook

Prof. Yoshimi will expand the target drugs whose doses need strict monitoring (eg. antibacterials, anticancers or immunosuppressant agents) for the new sensor technology.

The new sensor will be demonstrated live at Medical Japan 2017 in INTEX OSAKA at Booth No. 12-38, 10:00-18:00, Feb 15-17.

Medical Japan 2017 Osaka

Date & time: 10:00-18:00 (10:00-17:00 on last day)
February 15~17, 2017

Venue: Booth No. 12-38, INTEX OSAKA

*For the live demonstration, please visit:
February 25, 2017
Seminar Booth N, Hall No.3, INTEX OSAKA


Planning and Public Relations Section

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