Linlin Lu
BME Ph.D. Defense Presentation
 
Date: Thursday, May 30

Time: 5 am - 6 am Atlanta time / 5 pm - 6 pm Beijing time
Location:  ZongHeKeYan Building (Room 425) - PKU 

https://bluejeans.com/987877370?src=join_info

 
Committee members:
Xiaojie Duan (Advisor)
Garrett B. Stanley (Co-Advisor)
Antony K. Chen 
Haifeng Chen
Youfan Hu

Yingying Zhang

Weihua Pei
 
Soft Carbon Nanotube Fiber Electrodes for Multimodal Neural Interfacing

Chronically implanted neural devices are highly needed for neuroscience studies as well as clinical applications. These devices are used to record extracellular electrical potential or stimulate tissues adjacent to implanting sites so as to associate brain with peripheral facilities. Devices like the cochlea implant, retinal prosthesis, deep brain stimulation electrodes are already widely used for conditions like deafness, blindness and diseases including epilepsy, essential tremor, depression and chronic pain. However, current implantable stimulating or recording electrodes are mainly made of noble materials, stainless steel, and crystalline silicon, which have gradual decaying function quality over time. The cause of decay is still under debate while most experts agree that glial scarring caused by continuous inflammation due to mechanical mismatch between devices and brain tissue increases electrode’s impedance and makes it difficult for devices’ functioning. Another problem of commonly used electrodes is their incompatibility with MRI, which makes it impossible to show the macroscopic brain structure of the tissue around implantation sites and surrounding tissues. In addition, MRI compatible devices enable patients with DBS electrodes in the brain to do magnetic resonance scanning without electrodes’ retrieve, which gives great convenience for patients. 
CNT fibers have low impedance and high charge injection limit, which makes them qualified for neural recording and stimulation with a tiny diameter. With softness attributed to small diameter, CNT fibers are supposed to cause less inflammation response, leading to chronic functionality as neural probes. And nonmetallic CNT fibers are less likely to cause artifacts in MRI due to their similar magnetic susceptibility to brain tissue. My research focuses on developing CNT fiber microelectrodes for chronic neural recording and MRI compatible use.