DNA-templated silver nanoclusters as label-free, sensitive detection probes for potassium ions and nitric oxide

Potassium-induced G-quadruplex DNAzyme as a chemiluminescent sensing platform for highly selective detection of K+

“…Potassium (K + ) plays a vital role in many kinds of metastasis of biological organisms, such as transmitting nerve, maintaining extracellular and intracellular osmolality and muscular strength, regulating the concentration of other ions. 1,2 Abnormal concentrations of K + in extracellular and intracellular uids will trigger a series of diseases, such as disorder heart rhythms and high blood. 3,4 Therefore, a simple, sensitive and selective detection method of K + is essential to biomedical clinical diagnosis, and it has been one of the most attractive eld for researchers.…”

“…3,4 Therefore, a simple, sensitive and selective detection method of K + is essential to biomedical clinical diagnosis, and it has been one of the most attractive eld for researchers. Although some prominent progress has been achieved, [1][2][3][4][5][6][7][8][9] selective detection of extracellular K + is still a challenge mainly due to the large excess of sodium and other trace metal elements in physiological conditions. Several techniques have been devised for resolving this difficulty in recent years.…”

Dengue serotyping with a label-free DNA sensor

“…36 Moreover the uorescence emission of AgNC is tunable by DNA sequence programming. 36,[45][46][47] The application of AgNCs for diagnostics is not new with examples of them having been used in miRNA detection, 42,46 cell imaging, 48 sensing, 49,50 cell labelling, 51 nucleic acid detection 52,53 and drug delivery. 54 The uorescence intensity generated by AgNCs could be measured by using a uorescence spectrophotometer since there is a direct correlation between the uorescence intensity and AgNC concentration (Fig.…”

“…The ratio of these two components has always been xed at 1 : 6 : 6, 1 : 12 : 12, or 1 : 18 : 18. 50,[55][56][57] An equal molar ratio of AgNO 3 and NaBH 4 is always applied in the formation of AgNCs because one mole of NaBH 4 is needed to reduce one mole of AgNO 3 into silver atoms (AgNO 3 + NaBH 4 / Ag + NaNO 3 + 1 2 B 2 H 6 + 1 2 H 2 ). 58 In this paper however, the molar ratio of AgNO 3 was three times higher than that of NaBH 4 .…”

Fluorescence switch for silver ion detection utilizing dimerization of DNA-Ag nanoclusters

“…Water-soluble DNA-templated Ag nanoclusters (DNA-AgNCs) fabricated by simple mixing and reduction process can be used for imaging or sensing probe that exploits their DNA sequence-dependent fluorogenic property (Lee et al 2014;Li et al 2012;Petty et al 2004;Richards et al 2008). N3 atoms and the carboxyl group in the pyrimidine ring of cytosine (Cyt) and the N atoms in the purine ring of guanine (Gua) are the most probable binding sites for Ag + during DNA-AgNCs formation, though the detailed mechanism has not yet been known (Arakawa et al 2001;DiRico et al 1985;Luk et al 1975).…”