A colorimetric selective sensing probe for calcium ions with tunable dynamic ranges using cytidine triphosphate stabilized gold nanoparticles

Cytidine triphosphate (CTP) stabilized-Au nanoparticles (CTP-AuNPs) allow a quantitative assay of Ca2+ down to a concentration of 10(-4) Mwith high selectivity towards Ca2+ ions over various metal ions including Mg2+ and the detection range of this probe also can be easily tuned by changing the concentration of CTP.