A high-nuclearity Cd(II)-Tb(III) nanocage for the rapid and quantitative time-resolved luminescence detection of guanosine-5-monophoshpate and RNA

Abstract

One 32-metal Cd(II)-Tb(III) nanocage 1 was obtained using a flexible Schiff base ligand. The addition of guanosine-5-monophosphate (GMP) and RNA of human pancreas cancer results in the Tb(III) luminescence (5D4 → 7Fn transitions, n = 6, 5, 4 and 3), which is dominated by the static enhancement model. 1 exhibits highly sensitive time-resolved luminescence (TRL) detection to GMP and RNA with a delay time of 500 μs, and the corresponding linear fitting equations are (I-I0)/I0 = 14502·CGMP + 856 and (I-I0)/I0 = 2421·CRNA + 1926, respectively. The limits of detection to GMP and RNA are 0.021 μM and 0.71 ng/μL, respectively, and 1 can be used to determine the concentrations of GMP and RNA accurately. 1 displays rapid and stable luminescence response to the analytes, with the response times less than five seconds and no changes for the lanthanide emission over one week.