Related Experiment Video
Updated: Jan 14, 2026
09:28
Engineering Molecular Recognition with Bio-mimetic Polymers on Single Walled Carbon Nanotubes
Published on: January 10, 2017
8.5K
Quantum Defects Engineered in Chirality Pure Single-Wall Carbon Nanotubes for Enabling Ratiometric Sensing of Insulin
Ali A Alizadehmojarad1, Hohyung Kang1, Gabriel Sánchez-Velázquez1
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|October 22, 2025
Summary
Researchers developed a new ratiometric nanosensor for insulin detection using quantum-defective, single-chirality carbon nanotubes. This improved Corona Phase Molecular Recognition (CoPhMoRe) method enhances sensitivity and simplifies spectral analysis for accurate hormone sensing.
Area of Science:
- Nanotechnology and Materials Science
- Biomedical Engineering
- Analytical Chemistry
Background:
- The Corona Phase Molecular Recognition (CoPhMoRe) method utilizes fluorescent semiconducting single-wall carbon nanotubes (SWCNTs) functionalized with heteropolymers for analyte detection.
- Current CoPhMoRe sensors face challenges in spectral complexity and sensitivity, particularly for detecting biomolecules like the hormone insulin.
Purpose of the Study:
- To enhance the CoPhMoRe method by incorporating quantum defects into SWCNTs for ratiometric sensing.
- To improve the selectivity and sensitivity of SWCNT-based sensors for insulin detection.
- To develop a scalable method for isolating single-chirality SWCNTs to simplify sensor fabrication and analysis.
Main Methods:
- Functionalization of SWCNTs with a C16 PEG2K Ceramide heteropolymer corona.
- Introduction of sp3 quantum defects into SWCNTs via UV irradiation in the presence of 5-iodoracil, creating a new E11* emission feature.
- Development and application of a scaled-up method for isolating single-chirality SWCNTs.
- Characterization of ratiometric sensor response using new metrics including spectral shift and intensity ratios (E11*/E11).
Main Results:
- The incorporation of quantum defects resulted in a dual emission profile (E11 and E11*) in SWCNTs.
- Chirality-sorted SWCNTs demonstrated a 20% greater fluorescence quenching by insulin compared to unsorted SWCNTs.
- The E11*/E11 ratio was precisely modulated in ratiometric sensors fabricated with sorted SWCNTs.
- A minimum E11*/E11 ratio of 3 was identified as optimal for ratiometric nanosensor transformation.
Conclusions:
- Chemically induced quantum defects and the use of chirality-sorted SWCNTs significantly improve CoPhMoRe sensor performance.
- The developed ratiometric nanosensor offers enhanced sensitivity and simplified analysis for insulin detection.
- This approach provides a robust platform for developing advanced nanosensors for various analytes.
