Paper-based OECTs and Circular Devices
Paper-based OECTs and Circular Devices
In last decade the chronic diseases have significantly increased while contributing to 75% of deaths globally. Conditions such as diabetes, blood pressure and dehydration have increased and it is essential to monitor these conditions and have a diagnostic plan. Among emerging technologies, the organic electrochemical transistors (OECTs) stand out as a potential candidate for biomedical sensing due to their high signal amplification and low operating voltages. OECTs are a three terminal device (Source, Drain and Gate) where the organic semiconducting material poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) can be used as a channel.
Traditionally, these devices have been fabricated on various bio-compatible substrates such as polyimide, PET and parylene. Contrarily to the commonly used channel material PEDOT:PSS, the substrates are not water soluble or biodegradable leading to long term electronic waste. In last decade the amount of electronic waste has doubled with Europe being the largest contributor. With the ongoing trend of wearable sensor systems, RFID tags and single use electronics has made it worse for recycling. Therefore, it is essential to substitute the substrate materials and an interesting candidate is the recycled paper which is sustainable and thereby enhancing the devices environmental compatibility without compromising performance. The paper industry is growing year by year and so is the recycled paper which is often used in packaging industry due to its low cost and abundance.
Our work focuses on developing new methods to implement OECTs on paper substrate without the need of cleanroom technologies for ensuring sustainability and scalability. Integrating microfluidic device for sweat sampling, sensing of human stress levels (Cortisol) through sweat and sensing of phosphate in plants, river water or soil are some of the examples of the ongoing projects.
