Batteryless solutions for implantable and wearable wireless medical devices

Récupération et transmission d'énergie pour électronique médicale intra- et extra-corporelle

Luigi Di Trocchio (1)

1 IMS - Laboratoire de l'intégration, du matériau au système

Electronic medical devices are nowadays blossoming, revolutionizing the way of think- ing the healthcare. These innovative devices are more and more frequently substituting the classical and conventional pharmaceutical approach to monitor and treat various diseases in different parts of the body, increasing results and limiting side effects. Re- cently, the advancements in bioelectronics have brought miniaturized implantable medical devices, which can be placed directly on the desired spot of the body, and wearable so- lutions, allowing the monitor of body parameters with minimum impact on the patients. Moreover, these devices are now embedding wireless communication capabilities, to allow the remote monitoring without needing unwanted wires. In order to further improve this technology, one of the most challenging and still not solved design problem is the research of a suitable powering approach, since classical batteries are not the optimal choice due to their size, weight and discharge in time. This dissertation proposes new batteryless solutions for both implantable and wearable wireless medical devices. On the implantable side, the first steps towards a highly integrated implantable micro- energy platform with communication capabilities are carried out. Two alternatives to batteries were selected to power the device: Wireless Power Transfer (WPT) and glucose Biofuel Cells (BFC). The first involves the transmission of energy from a transmitter to a receiver via an oscillating magnetic field and the second uses living organisms to produce electricity, using glucose and oxygen, both very abundant inside the human body. The proposed design is able to merge these two technologies in one single object, having both antenna and electrode capabilities, in order to allow a further miniaturization of the platform while having a hybrid powering system. Regarding wearable devices, fully-passive Ultra High Frequency Radio Frequency Identification (UHF-RFID) sensor solutions are proposed with application on laboratory rodents and human healthcare. In this work, the proposed hybrid implantable technology was successfully validated. Improvements of the structure, starting from a simple design, were defined and proven, in order to increase the efficiency of the wireless link. This allows to reduce the impact of dielectric losses associated to the body environment, while keeping the antenna/electrode in contact with the tissues. Moreover, four wearable RFID sensors were developed in order to continuously monitor a BFC implanted in a laboratory rat, leading to successfully monitoring of a BFC in-vivo for about 24 hours. Finally, a passive ultra-low-cost wearable RFID tag, with temperature monitoring capabilities, was also designed and developed using corrugated cardboard as substrate, allowing the easy screening of the human body temperature in developing countries, in case of emergencies or diseases outbreak.

Ce travail de doctorat fait partie d'un projet multidisciplinaire, dont le but est de développer de nouveaux capteurs biomédicaux implantables, sans fil et qui fonctionnent sans moyens de batterie. La thèse se concentrera sur la partie électronique de ces implants. Des solutions novatrices seront proposées afin d'alimenter les appareils et d'optimiser la communication avec l'extérieur du corps. La communication se fera par le biais d'un lien radiofréquence et, en ce qui concerne la source d'alimentation, nous prévoyons utiliser deux alternatives aux batteries: transfert de puissance sans fil et biopiles. Le premier implique la transmission d'énergie d'un émetteur à un récepteur via un champ magnétique oscillant et le second utilise des organismes vivants pour produire de l'électricité, en utilisant du glucose et de l'oxygène, tous deux très abondants à l'intérieur du corps humain.

Mots clés: Implantable device; Wearable device; Wireless Power Transfer; RFID; Biofuel cell

Mots clés: RFID; Récupération d’énergie sans fils; Dispositif implantable; Électronique médicale; Biopile

Domaines: Micro et nanotechnologies/Microélectronique; Instrumentations et Détecteurs [physics.ins-det]; Ingénierie biomédicale

Luigi Di Trocchio. Batteryless solutions for implantable and wearable wireless medical devices. Micro and nanotechnologies/Microelectronics. Université de Bordeaux, 2019. English. ⟨NNT : ⟩. ⟨tel-02519390⟩