Development of Nanobiosensing platform at a 10nm scale

2020 Fiscal Year Annual Research Report

• Project/Area Number: 19F19801
• Research Institution: The University of Tokyo
• Principal Investigator: 藤井 輝夫 東京大学, 生産技術研究所, 教授 (30251474)
• Co-Investigator(Kenkyū-buntansha): LI SHUO 東京大学, 生産技術研究所, 外国人特別研究員
• Project Period (FY): 2019-11-08 – 2022-03-31
• Keywords: Nanodots array / Electrochemistry / Biosensor / Apatmer / Microfluidic device

Outline of Annual Research Achievements

In this project, we explore the challenges and opportunities of the development of a new class of versatile, mass-fabrication compatible sensors in the 10 nm range by using electrochemical approach. The 10 nm range is an ideal length scale for statistical analysis, single entity measurement and for taking advantages of unique features. Following results were achieved in this fiscal year:(i)Tuned the density of the bio molecules to get ideal sensor probe. (ii)Developed mixed self-assembled-monolayer to increase the stability of the sensor and avoid nonspecific binding with undesired materials. (iii)Fabricated and optimized nanostructure by using e-beam lithography to improve the properties of the device. (iv)The device has been used to test with different types of cancer cells, which showed specific property to bind with target. (v)The device has been combined with micro-fluidic system to specify the target and non target with different fluidity by checking with fluorescent microscope. (vi)Created theory to combine with the experiment, a nice model has been simulated to show the interaction between the sensor probe and target.(vii)Fabricated 10 nm nanodots array, which will be used to demonstrate for single-molecule arrays. The device will be tested in biological environment, and for further studying the information of trapped CTCs.

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

Until now, the first design of the sensor has been successfully developed by optimizing configuration of the sensor. Cell detection performance of the sensor has been successfully demonstrated by detecting and analyzing electrochemical signals from cancer cells. At the same time, nanodot array with diameters ranging from 10 nm to 500 nm has been successfully fabricated in 1.5 mm × 1.5 mm area by using e-beam lithography after optimization of the fabrication process. According to the research plan, most of the research steps have been accomplished. Measurement of the electrochemical signal with a single molecule per dot will be demonstrated in the following moths as a last step of this research.

Strategy for Future Research Activity

The theory part will be mainly progressed to combine it with current experiment results, which is also significant to optimize the device and make sure the platform is more efficient. Then, the concept of single DNA per dot will be demonstrated using novel nanodot arrays.