Toward biosensors for the detection of circulating microRNA as a cancer biomarker: an overview of the challenges and successes.

Considerable attention has been dedicated to developing feasible point-of-care tests for cancer diagnosis and prognosis. An ideal biomarker for clinical use should be easily assayed with minimally invasive medical procedures but possess high sensitivity and specificity. The role of microRNAs (miRNAs) in the regulation of different cellular processes, the unique altered patterns in cancer patients and presence in body fluids in the stable form, points to their clinical utility as blood-based biomarkers for diagnosis, prognosis, and treatment of cancer.

A novel route to copper(II) detection using 'click' chemistry-induced aggregation of gold nanoparticles.

A simple colorimetric method for the detection of copper ions in water is described. This method is based on the 'click' copper(I)-catalyzed azide-alkyne cycloaddition reaction and its use in promoting the aggregation of azide-tagged gold nanoparticles by a dialkyne cross-linker is described. Nanoparticle cross-linking, evidenced as a colour change, is used for the detection of copper ions.