Materials, Mechanics Designs, and Bioresorbable Multisensor Platforms for Pressure Monitoring in the Intracranial Space

• Published in: Advanced functional materials Vol. 30; no. 17
• Main Authors: Yang, Quansan, Lee, Seungae, Xue, Yeguang, Yan, Ying, Liu, Tzu‐Li, Kang, Seung‐Kyun, Lee, Yung Jong, Lee, Seok Hwan, Seo, Min‐Ho, Lu, Di, Koo, Jahyun, MacEwan, Matthew R., Yin, Rose T., Ray, Wilson Z., Huang, Yonggang, Rogers, John A.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.04.2020
• Subjects: bioabsorbable electronics; Biocompatibility; biomedical implants; Biomedical materials; Encapsulation; Materials science; Monitoring; Multisensor applications; Pressure sensors; Sensors; Surgical implants; transient electronics
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201910718

Pressures in the intracranial, intraocular, and intravascular spaces are important parameters in assessing patients with a range of conditions, of particular relevance to those recovering from injuries or from surgical procedures. Compared with conventional devices, sensors that disappear by natural processes of bioresorption offer advantages in this context, by eliminating the costs and risks associated with retrieval. A class of bioresorbable pressure sensor that is capable of operational lifetimes as long as several weeks and physical lifetimes as short as several months, as combined metrics that represent improvements over recently reported alternatives, is presented. Key advances include the use of 1) membranes of monocrystalline silicon and blends of natural wax materials to encapsulate the devices across their top surfaces and perimeter edge regions, respectively, 2) mechanical architectures to yield stable operation as the encapsulation materials dissolve and disappear, and 3) additional sensors to detect the onset of penetration of biofluids into the active sensing areas. Studies that involve monitoring of intracranial pressures in rat models over periods of up to 3 weeks demonstrate levels of performance that match those of nonresorbable clinical standards. Many of the concepts reported here have broad applicability to other classes of bioresorbable technologies. Monocrystalline silicon and natural wax materials serve as the basis for bioresorbable pressure sensors with operational lifetimes as long as several weeks and physical lifetimes as short as several months. Optimized mechanics designs yield stable operation as the encapsulation materials dissolve and disappear. Many of the concepts reported here have broad applicability to other classes of bioresorbable technologies.