Formulation of DNA chimera templates: Effects on emission behavior of silver nanoclusters and sensing

Ratiometric Detection of microRNA Using Hybridization Chain Reaction and Fluorogenic Silver Nanoclusters

“…HCR‐positive). This is in accordance to the dual‐emissive character of the AgNCs hosted at the nucleating sequence of H1, as aforementioned [20] . Without miR‐155, the hairpin structure of H1 remained conserved, whereby four cytosine bases at the 5’‐end of the H1 toehold region come in close proximity to the AgNCs and result in predominance of red emission.…”

“…H1 was designed to have a nucleation sequence of AgNCs (‐ ACC CAC CCA ‐) at the end of the hairpin structure. This sequence was previously reported to produce yellow and red emissive species, with the former as dominant [20] . Inspired by the concept of nanocluster beacons, where their optical property is known to be influenced by adjacent bases, [21] we deduce that the AgNCs hosted in H1 will change their fluorescence profile when the hairpin unfolds during HCR.…”

“…This is in accordance to the dualemissive character of the AgNCs hosted at the nucleating sequence of H1, as aforementioned. [20] Without miR-155, the hairpin structure of H1 remained conserved, whereby four cytosine bases at the 5'-end of the H1 toehold region come in close proximity to the AgNCs and result in predominance of red emission. When HCR was triggered by miR-155, the nucleating sequence was separated from the toehold region, leading to enhancement of yellow fluorescence.…”

“…This sequence was previously reported to produce yellow and red emissive species, with the former as dominant. [20] Inspired by the concept of nanocluster beacons, where their optical property is known to be influenced by adjacent bases, [21] we deduce that the AgNCs hosted in H1 will change their fluorescence profile when the hairpin unfolds during HCR. Considering cytosine-rich bases could result in AgNCs of greater size and with longer emission wavelength, [22] we hence introduced four cytosine bases in the toehold region of H1 (i. e. opposite to the region containing nucleation sequence).…”

Recent advances in optical biosensing and imaging of telomerase activity and relevant signal amplification strategies

“…The specific quenching was attributed to the formation of parallel G-quadruplexes, since the authors have demonstrated that an anti-parallel G-quadruplex showed a relatively lower quenching efficiency. 35 Furthermore, the effect of the number of TTAGGG repeats (R n ) on the fluorescence of AgNCs was investigated. Compared to the fluorescence of Ct 9 TS-AgNCs without any telomeric repeats, the emission intensity of Ct 9 TSR n -AgNCs decreased by about 50% in TRAP buffer due to the formation of a parallel G-quadruplex (Fig.…”