Design and fabrication of an ubiquitous, low-cost, and wearable respiratory bio-sensor using ionic soft materials

The respiratory system is a vital organ system which makes breathing and gas exchange possible for human's body. The loss of functionality in this system is due to either genetical problems or environmental issues like pollution or toxic gases which in many cases is inevitable. These circumstances may cause different respiratory diseases which may not be curable presently but their side effects can be partly controlled by careful and timely analysis improving the quality of patient's life. So, an appropriate device for conducting different analysis can be effective for people who suffer from respiratory diseases such as chronic obstructive pulmonary disease (COPD), asthma, occupational lung diseases, and pulmonary hypertension to facilitate various tests and measurements. In this paper, an ionic electroactive polymer-based soft sensor has been introduced which can carefully detect the breathing patterns and has promising features to develop low cost, wearable, and ubiquitous spirometers. The proposed sensor is a small strip of Ionic Polymer Metal Composite (IPMC) that we have fabricated using a Nafion membrane and Pt electrodes. A series of experiments were designed and performed for several male and female subjects. Results showed that the IPMC sensor can detect different breathing patterns with various frequencies in a perfect manner.