title: Bioresorbable silicon electronic sensors for the brain.
abstract: Many procedures in modern clinical medicine rely on the use of electronic implants in treating conditions that range from acute coronary events to traumatic injury. However, standard permanent electronic hardware acts as a nidus for infection: bacteria form biofilms along percutaneous wires, or seed haematogenously, with the potential to migrate within the body and to provoke immune-mediated pathological tissue reactions. The associated surgical retrieval procedures, meanwhile, subject patients to the distress associated with re-operation and expose them to additional complications. Here, we report materials, device architectures, integration strategies, and in vivo demonstrations in rats of implantable, multifunctional silicon sensors for the brain, for which all of the constituent materials naturally resorb via hydrolysis and/or metabolic action, eliminating the need for extraction. Continuous monitoring of intracranial pressure and temperature illustrates functionality essential to the treatment of traumatic brain injury; the measurement performance of our resorbable devices compares favourably with that of non-resorbable clinical standards. In our experiments, insulated percutaneous wires connect to an externally mounted, miniaturized wireless potentiostat for data transmission. In a separate set-up, we connect a sensor to an implanted (but only partially resorbable) data-communication system, proving the principle that there is no need for any percutaneous wiring. The devices can be adapted to sense fluid flow, motion, pH or thermal characteristics, in formats that are compatible with the body's abdomen and extremities, as well as the deep brain, suggesting that the sensors might meet many needs in clinical medicine.
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Seung-Kyun
authors.initials: SK
authors.lastname: Kang
authors.affiliation: Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Rory K J
authors.initials: RK
authors.lastname: Murphy
authors.affiliation: KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Suk-Won
authors.initials: SW
authors.lastname: Hwang
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Seung Min
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Daniel V
authors.initials: DV
authors.lastname: Harburg
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Neil A
authors.initials: NA
authors.lastname: Krueger
authors.affiliation: Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Jiho
authors.initials: J
authors.lastname: Shin
authors.affiliation: Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Gamble
authors.affiliation: Department of Engineering Science and Mechanics, Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Huanyu
authors.initials: H
authors.lastname: Cheng
authors.affiliation: Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Sooyoun
authors.initials: S
authors.lastname: Yu
authors.affiliation: Institute of High Performance Computing, Singapore 138632, Singapore.
authors.forename: Zhuangjian
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Anesthesiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Jordan G
authors.initials: JG
authors.lastname: McCall
authors.affiliation: Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Manu
authors.initials: M
authors.lastname: Stephen
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Hanze
authors.initials: H
authors.lastname: Ying
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Jeonghyun
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Biomicrosystem Technology, Korea University, Seoul 136-701, South Korea.|Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul 136-713, South Korea.
authors.forename: Gayoung
authors.initials: G
authors.lastname: Park
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: R Chad
authors.initials: RC
authors.lastname: Webb
authors.affiliation: Weldon School of Biomedical Engineering, School of Mechanical Engineering, The Center for Implantable Devices, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Chi Hwan
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Sangjin
authors.initials: S
authors.lastname: Chung
authors.affiliation: School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Dae Seung
authors.initials: DS
authors.lastname: Wie
authors.affiliation: Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Amit D
authors.initials: AD
authors.lastname: Gujar
authors.affiliation: Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Bharat
authors.initials: B
authors.lastname: Vemulapalli
authors.affiliation: Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Albert H
authors.initials: AH
authors.lastname: Kim
authors.affiliation: Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul 136-713, South Korea.
authors.forename: Kyung-Mi
authors.initials: KM
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Cheng
authors.affiliation: Department of Mechanical Engineering, Civil and Environmental Engineering, Materials Science and Engineering, and Skin Disease Research Center, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: Younggang
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Biomedical Engineering, College of Health Science, Korea University, Seoul 136-703, South Korea.
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Paul V
authors.initials: PV
authors.lastname: Braun
authors.affiliation: Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Wilson Z
authors.initials: WZ
authors.lastname: Ray
authors.affiliation: Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.|Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Rogers
mesh_terms: D020341:Absorbable Implants / Q000009:adverse effects; D000279:Administration, Cutaneous; D000818:Animals; D001831:Body Temperature; D001921:Brain / Q000378:metabolism* / Q000601:surgery; D004581:Electronics / Q000295:instrumentation*; D004867:Equipment Design; D006868:Hydrolysis; D008297:Male; D008991:Monitoring, Physiologic / Q000009:adverse effects / Q000295:instrumentation*; D009928:Organ Specificity; D011312:Pressure; D019736:Prostheses and Implants / Q000009:adverse effects; D051381:Rats; D011917:Rats, Inbred Lew; D012825:Silicon; D013686:Telemetry / Q000295:instrumentation; D059015:Wireless Technology / Q000295:instrumentation
chemical_list: D012825:Silicon