Theranostics 2012; 2(7):631-654. doi:10.7150/thno.4308

Review

Quantum Dot Enabled Molecular Sensing and Diagnostics

Yi Zhang1, Tza-Huei Wang2 ✉

1. Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
2. Department of Biomedical Engineering, Department of Mechanical Engineering, Sidney Kimmel Comprehensive Cancer Center, Center of Cancer Nanotechnology Excellence, Johns Hopkins University, Baltimore, MD 21205, USA.

Abstract

Since its emergence, semiconductor nanoparticles known as quantum dots (QDs) have drawn considerable attention and have quickly extended their applicability to numerous fields within the life sciences. This is largely due to their unique optical properties such as high brightness and narrow emission band as well as other advantages over traditional organic fluorophores. New molecular sensing strategies based on QDs have been developed in pursuit of high sensitivity, high throughput, and multiplexing capabilities. For traditional biological applications, QDs have already begun to replace traditional organic fluorophores to serve as simple fluorescent reporters in immunoassays, microarrays, fluorescent imaging applications, and other assay platforms. In addition, smarter, more advanced QD probes such as quantum dot fluorescence resonance energy transfer (QD-FRET) sensors, quenching sensors, and barcoding systems are paving the way for highly-sensitive genetic and epigenetic detection of diseases, multiplexed identification of infectious pathogens, and tracking of intracellular drug and gene delivery. When combined with microfluidics and confocal fluorescence spectroscopy, the detection limit is further enhanced to single molecule level. Recently, investigations have revealed that QDs participate in series of new phenomena and exhibit interesting non-photoluminescent properties. Some of these new findings are now being incorporated into novel assays for gene copy number variation (CNV) studies and DNA methylation analysis with improved quantification resolution. Herein, we provide a comprehensive review on the latest developments of QD based molecular diagnostic platforms in which QD plays a versatile and essential role.

Keywords: Quantum Dot, Diagnostics, Sensing, Nanosensor, Nanoassembly.

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How to cite this article:
Zhang Y, Wang TH. Quantum Dot Enabled Molecular Sensing and Diagnostics. Theranostics 2012; 2(7):631-654. doi:10.7150/thno.4308. Available from http://www.thno.org/v02p0631.htm