Single-molecule fluorescence detection of a tricyclic nucleoside analogue

Abstract

Fluorescent nucleoside analogue ABN is readily detected at the single-molecule level and retains a quantum yield >50% in duplex DNA oligonucleotides.

Determination of two-photon absorption in nucleobase analogues: a QR-DFT perspective

“…However, given that qAnitro is not reported to fluoresce, it cannot be recommended for use as this property is independent of the OPA or TPA methods used. Instead, we can look to the structure of qAnitro, coupled with the newly presented ABN analogue [67], for insight into the design of analogues with high cross sections. As can be seen in the orbital transitions of qAnitro (figures 4 & 5), and the word done by Samaan et.…”

“…al. [67], there is significant merit in pursuing the construction of a push-pull motifs, commonly considered a hallmark of optically bright organic fluorophores, as a mechanism for enhancing the TPA cross section of future FBAs.…”

“…A number of analogues have previously been investigated experimentally for two-photon viability, including: 2AP [30,64], 6-MI [64,65], 6MAP [66], ABN [67], pA [38,38,68] and tC [30]. This paper looks to expand this investigation to a wider range of commonly utilised analogues (Fig.…”

Fundamental photophysics of isomorphic and expanded fluorescent nucleoside analogues

“…Adapted from ref. 337 More recently, using rhodamine B as a model, Purse et al further modified the push-pull properties of tC by introducing ABN (Figure 34E) 340 . The free nucleoside, present only in the T-like tautomeric form, had an absorption and fluorescence maxima centered at 442 nm (ε = 20 000 M -1 cm -1 ) and 540 nm (ΦF=0.39), respectively.…”

Multicolor fluorescence encoding of different microRNAs in lung cancer tissues at the single-molecule level

“…Single-molecule detection has gained overwhelming attention due to high signal-to-noise ratio, low sample consumption, and ultrahigh sensitivity. [41][42][43][44][45][46] We used two lung cancer biomarkers miR-155 and miR-21 as the targets. The presence of miR-155 and miR-21 can initiate three consecutive amplification reactions (i.e., cyclic strand displacement amplification (SDA), APE1-assisted cyclic cleavage, and rolling circle amplification (RCA)), converting extremely low abundant target miRNAs to abundant Cy5/Cy3 fluorophores-encoded DNA products whose digestion releases larger numbers of fluorescent molecules.…”