There were over 8 million cancer-related deaths worldwide in 2013. According to the World Health Organization, this death toll will reach 13.1 million by 2030 unless rapid and cost- effective diagnostic technologies are developed for the early detection of the disease. Current diagnostic techniques such as ELISA are time-consuming for point-of-care settings and often cost-prohibitive for developing countries where resources are scarce. Here, we propose a potentially transformative all-carbon electronic biosensor based on a tube-in-a-tube semiconductor (Tube^2) created by our research team. A Tube^2 is composed of an atom-thick semiconductor nested within a charged, covalent functional shell. We hypothesize that conductance through the semiconductor can be completely controlled solely by surface functional groups on the shell such that binding of a small number of targeted cancer markers can be detected electrically. Our preliminary studies have shown evidence of chemically gated field effect detection of DNA using thin-film Tube^2 sensors. The proposed research will focus on three specific aims: 1) establishing the fundamentals of electrode-free chemical gating of Tube^2; 2) coaxial chemical lithography with light; and 3) label-free and multiplexed detection of cancer biomarkers by Tube^2 sensors.
In Aim 1, a series of aryl functional groups will be attached covalently at controlled densities on Tube^2 to quantitatively determine the gating effects of surface functional groups.
In Aim 2, we will investigate light-driven defunctionalization and re-functionalization of Tube^2 as the basis for a straightforward, fundamentally new fabrication approach to electronic sensor arrays.
In Aim 3, chemically gated field effect detection of model cancer markers, including prostate-specific antigen and -fetoprotein, will be investigated in thin-film Tube^2 sensor arrays. This work may provide a new foundation for the development of rapid and cost-effective medical diagnostic technologies.

Public Health Relevance

This proposal describes a new biosensor based on fundamental studies of chemical gating effects on a synthetic semiconductor. The bioanalytical potential of the proposed sensor will be evaluated using DNA and model cancer biomarkers. The proposed work will lay the foundation for the development of a rapid and cost-effective medical diagnostic technology.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Project (R01)
Project #
Application #
Study Section
Nanotechnology Study Section (NANO)
Program Officer
Wehrle, Janna P
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Maryland College Park
Earth Sciences/Resources
College Park
United States
Zip Code
Ng, Allen L; Chen, Chien-Fu; Kwon, Hyejin et al. (2017) Chemical Gating of a Synthetic Tube-in-a-Tube Semiconductor. J Am Chem Soc 139:3045-3051
Wang, Chunyan; Meany, Brendan; Wang, YuHuang (2017) Optically Triggered Melting of DNA on Individual Semiconducting Carbon Nanotubes. Angew Chem Int Ed Engl 56:9326-9330
Peng, Zhiwei; Ng, Allen L; Kwon, Hyejin et al. (2017) Graphene as a functional layer for semiconducting carbon nanotube transistor sensors. Carbon N Y 125:49-55
Ng, Allen L; Piao, Yanmei; Wang, YuHuang (2017) Laser Lithography of a Tube-in-a-Tube Nanostructure. ACS Nano 11:3320-3327
K?os, Jacek; Kim, Mijin; Alexander, Millard H et al. (2016) Chemical Control and Spectral Fingerprints of Electronic Coupling in Carbon Nanostructures. J Phys Chem C Nanomater Interfaces 120:29476-29483
Powell, Lyndsey R; Piao, Yanmei; Wang, YuHuang (2016) Optical Excitation of Carbon Nanotubes Drives Localized Diazonium Reactions. J Phys Chem Lett 7:3690-4
Kwon, Hyejin; Furmanchuk, Al'ona; Kim, Mijin et al. (2016) Molecularly Tunable Fluorescent Quantum Defects. J Am Chem Soc 138:6878-85