Non-Contact Biosensors Based On Smart Mobile Devices

Non-contact technology has been widely used in biosensor field.Combining the non-contact technology to biosensors can avoid secondary pollution caused by directly contact,leave out the trouble caused by changing related devices,reduce the cost of experiment and observation,increase the flexibility of sensor applications,and make it possible of 24 hours continuous monitoring.However,there are limited reports on portable detections using POCT devices due to the complexity of the principle,detection circuits and instruments.While the non-contact technology based on the smart mobile devices will provide an important development in the field of medical health.Herein,we applied the non-contact technology and smart phone to biosensors to fabricate more intelligentized and miniaturized biosensors.The detailed work is as follows.(1)In aspect of signal detection,we designed an optical detection platform based on smartphone camera and used this platform for electrochemically detection of saliver a-amylase.The paper-based sensing chip was proposed and the principles are studied.The special android APP was developed and a series of image processing algorithms were proposed to analyze the captured images.The paper-based sensing chip could be batch produced,the detection progress was automatically controlled by the software and algorithms,and the detection sample amount wasnot restricted,which provided adequate supports for the large analysis demand of POCT.(2)In aspect of energy supply,we developed a wireless charge system based on the electromagnetic induction principle,and applied the wireless charge system to lactic acid detection successfully.Aim to improve the efficiency of wireless transmission,we designed transmitting circuit,receiving circuit and PCB coils.The output voltage was 0.9?1.5 V within 5 mm transmission distance.A sensing array was fabricated based on electrochromism and the detection result could be read semi-quantitatively using naked eyes,and also could be analyzed more accurately using smartphone camera.Worth mentioning is that the amount of charge stored in the PB spot can be adjusted to match the detection limit and range of the sensor for specific clinical needs.(3)In aspect of signal transmittion,we combined wifi technology to ion detection in order to validate the feasibility of wearable device.A flexible circuit was produced to sample and transmit the data from ion sensors.A smartphone was used to receive data using wifi,present the result,and send to the server for storage.