Development of a quantum-dot-labelled magnetic immunoassay method for circulating colorectal cancer cell detection.

Aim: To detect of colorectal cancer (CRC) circulating tumour cells (CTCs) surface antigens, we present an assay incorporating cadmium selenide quantum dots (QDs) in these paper.

Methods: The principle of the assay is the immunomagnetic separation of CTCs from body fluids in conjunction with QDs, using specific antibody biomarkers: epithelial cell adhesion molecule antibody, and monoclonal cytokeratin 19 antibody. The detection signal was acquired from the fluorescence signal of QDs.

Quantum dots hold promise for early cancer imaging and detection.

Despite all major breakthroughs in recent years of research concerning the complex events that lead to cancer expression and metastasis, we are not yet able to effectively treat cancer that has spread to vital organs. The various clinical phases originating from cancer diagnosis through treatment and prognosis require a comprehensive understanding of these events, to utilise pre-symptomatic, minimally invasive and targeted cancer management techniques. Current imaging modalities such as ultrasound, computed tomography, magnetic resonance imaging and gamma scintigraphy facilitate the pre-operative study of tumours, but they have been rendered unable to visualise cancer in early stages, due to their intrinsic limitations.