Graphene Quantum Dots and Graphene Oxide-Based Biosensors for Detection of Cancer Biomarkers and Heavy Metals

Generally organic dye molecules are used as both the energy donor and acceptor in fluorescence resonance energy transfer (FRET) systems.^1,2 However, organic dyes suffer  from photobleaching. Graphene and graphene oxide (GO) were recently developed as both the donor and the acceptor for energy transfer-based fluorescent sensors.^3-5 A fluorescent dye to graphene follows the nano-surface energy transfer (NSET) mechanism.

Herein a fluorescent sensor based on the quantum dot (QD)/aptamer-GO complex is constructed in which GO acts an energy acceptor. This sensor is highly sensitive to Pb(II) with a limit of detection of 90 pM. On the other hand, with GO as the energy donor, a fluorescent sensor has also been developed for Hg²⁺ detection.

In addition, graphene quantum dots have been used as the energy acceptor to build fluorescent sensor for cancer biomarker detection.

This work was financially supported by a NSF grant (CBET-1336205). The resource and facilities used were partially supported by NSF (EPS 1003907) and a Research Challenge Grant from the State of West Virginia (EPS08-01).

REFERENCES AND NOTES

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(2)   M. Li, H. Gou, I. Al-Ogaidi, N. Q. Wu, Nanostructured sensors for detection of heavy metals: a review, ACS Sustainable Chemistry & Engineering, 1 (2013), 713-723

(3)   M. Li, X. Zhou, S. Guo, N. Q. Wu, Detection of lead (II) with a "turn-on" fluorescent biosensor based on energy transfer from CdSe/ZnS quantum dots to graphene oxide, Biosensors and Bioelectronics, 43 (2013), 69-74.

(4)   M. Li, X. Zhou, W. Ding, S. Guo, N. Q. Wu, Fluorescent aptamer-functionalized graphene oxide biosensor for label-free detection of Mercury(II), Biosensors and Bioelectronics, 41 (2013), 889-893

(5)   I. Al-Ogaidi, H. Gou, Z. P. Aguilar, S. Guo, A. K. Melconian, A. Kareem A. Al-kazaz, F. Meng*, and N. Q. Wu, Detection of the ovarian cancer biomarker CA-125 using chemiluminescence resonance energy transfer to graphene quantum dots, Chemical Communications, 50 (2014), 1344-1346