Highly Sensitive Nanostructured Electrical Paper Sensors: Low-Cost and Fast Detection of Protein Biomarkers
Final Report Abstract
My main project involved developing a paper-based printed respiration sensor that can be used for the detection of various respiratory illnesses and the measuring of performance in athletes. We produced a paper-based moisture sensor that uses the hygroscopic character of paper (i.e. the ability of paper to adsorb water reversibly from the surrounding environment) to measure patterns and rate of respiration by converting the changes in humidity caused by cycles of inhalation and exhalation to electrical signals. The changing level of humidity that occurs in a cycle causes a corresponding change in the ionic conductivity of the sensor, which can be measured electrically. By combining the paper sensor with conventional electronics, data concerning respiration can be transmitted to a nearby smartphone or tablet computer for post-processing, and subsequently to a cloud server. This means of sensing provides a new, practical method of recording and analyzing patterns of breathing. We tested the system developed, in an IRB approved human trial consisting of seven healthy subjects from the Whitesides Lab, at rest and during physical activity. The system was able to measure both the rate and the relative volumes of respiration, defined by an empirical metric called the Breathing Index (BI). The paper sensor, electronics and the mobile app, performed without failure or interruption of data during the experiments, and thus have the potential to be used for monitoring breathing, both at rest and during physical activity. The custom-built Android app running on the tablet computer/smartphone has the ability to run simple analytics (e.g. Fourier transforms) on the incoming data stream, and apply digital filtering algorithms for signal processing. Both the raw and the filtered data can be uploaded to the cloud and shared with a healthcare professional with the click of a button, thus eliminating unnecessary visits to the clinic. This system is non-invasive, and thus allows physical scientists access to physiologically relevant human data under simple IRB approvals. Operation is sufficiently simple that inexperienced, first-time users can be trained in a matter of a few minutes; all they have to do is to put on the mask, run the Android app and click on “start” to monitor and record respiration.
Publications
- “Stepped Moduli in Layered Composites”, Advanced Functional Materials 2014, 45, p.7197-7204
J-H. So, A. Tayi, F. Güder, and G. M. Whitesides
(See online at https://doi.org/10.1002/adfm.201401548) - “Analytical Devices Based on Direct Synthesis of DNA on Paper”, Analytical Chemistry 2015, 88, p.725-731
A. C. Glavan, J. Niu, Z. Chen, F. Güder, C. M. Cheng, D. Liu, G. M. Whitesides
(See online at https://doi.org/10.1021/acs.analchem.5b02822) - “Electrically Activated Paper Actuators”, Advanced Functional Materials 2016, 26 p.2446–2453
M. M. Hamedi, V. E. Campbell, P. Rothemund, F. Güder, D. C. Christodouleas, J-F. Bloch, G. M. Whitesides
(See online at https://doi.org/10.1002/adfm.201505123) - “Integrating Electronics and Microfluidics on Paper”, Advanced Materials 2016
M. M. Hamedi, A. Ainla, F. Güder, D. C. Christodouleas, M. T. Fernández-Abedul, G. M. Whitesides
(See online at https://doi.org/10.1002/adma.201505823) - “Paperbased Electrical Respiration Sensor”, Angewandte Chemie Int. Ed. 2016, 55, p.5727– 5732
F. Güder, A. Ainla, J. Redston, B. Mosadegh, A. Glavan, G. M. Whitesides
(See online at https://doi.org/10.1002/anie.201511805)
