Analytical and Bioanalytical Chemistry

, Volume 397, Issue 8, pp 3213–3224 | Cite as

Use of quantum dots in the development of assays for cancer biomarkers

  • Megan K. Wagner
  • Feng Li
  • Jingjing Li
  • Xing-Fang Li
  • X. Chris Le
Review

Abstract

Biomarker assays may be useful for screening and diagnosis of cancer if a set of molecular markers can be quantified and statistically differentiated between cancerous cells and healthy cells. Markers of disease are often present at very low concentrations, so methods capable of low detection limits are required. Quantum dots (QDs) are nanoparticles that are emerging as promising probes for ultrasensitive detection of cancer biomarkers. QDs attached to antibodies, aptamers, oligonucleotides, or peptides can be used to target cancer markers. Their fluorescent properties have enabled QDs to be used as labels for in-vitro assays to quantify biomarkers, and they have been investigated as in-vivo imaging agents. QDs can be used as donors in assays involving fluorescence resonance energy transfer (FRET), or as acceptors in bioluminescence resonance energy transfer (BRET). The nanoparticles are also capable of electrochemical detection and are potentially useful for “lab-on-a-chip” applications. Recent developments in silicon QDs, non-blinking QDs, and QDs with reduced-size and controlled-valence further make these QDs bioanalytically attractive because of their low toxicity, biocompatibility, high quantum yields, and diverse surface modification flexibility. The potential of multiplexed sensing using QDs with different wavelengths of emission is promising for simultaneous detection of multiple biomarkers of disease.

Figure

Quantum dots have been conjugated to affinity probes to assay for cancer biomarkers including proteins, peptides, DNA, and whole cells

Keywords

Quantum dots Nanoparticles Tumor markers Imaging Biosensors Fluorescence FRET BRET Electrochemical Multiplex Aptamers Cancer 

Abbreviations

AFP

α-Fetoprotein

BPDE

Benzo[a]pyrene diol epoxide

BRET

Bioluminescence resonance energy transfer

CA

Cancer antigen

CEA

Carcinoembryonic antigen

CK18

Cytokeratin 18

DNA

Deoxyribonucleic acid

ELISA

Enzyme-linked immunosorbent assay

FRET

Fluorescence resonance energy transfer

HER2

Human epidermal growth factor receptor 2

IgG

Immunoglobulin G

MMP

Matrix metalloproteinase

MUC1

Mucin 1

PCR

Polymerase chain reaction

PEG

Poly(ethylene glycol)

PSA

Prostate-specific antigen

PSMA

Prostate-specific membrane antigen

QD

Quantum dot

RCA

Rolling circle amplification

RNA

Ribonucleic acid

SELEX

Systematic evolution of ligands by exponential enrichment

uPA

Urokinase-type plasminogen activator

VEGF

Vascular endothelial growth factor

Notes

Acknowledgements

The authors thank the Natural Sciences and Engineering Research Council of Canada, Canadian Institutes of Health Research, the Canada Research Chairs program, and Alberta Health and Wellness for their support. An Alberta Ingenuity Nanotechnology Scholarship (to MKW) and a China Scholarship Council visiting studentship (to JL) are also acknowledged.

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Megan K. Wagner
    • 1
  • Feng Li
    • 1
  • Jingjing Li
    • 1
  • Xing-Fang Li
    • 1
  • X. Chris Le
    • 1
  1. 1.Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, 10-102 Clinical Sciences BuildingUniversity of AlbertaEdmontonCanada

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