A novel and photostable pH probe for selectively staining nuclei in living cells

Abstract

A novel pH probe based on hemi-cyanine was synthesized, which displays extremely large Stokes shift (122 nm) and good photostability. The probe responds to basic pH (pKa 8.32) with a colorimetric and fluorescence turn-on signal. Interestingly, the probe has good cell membrane permeability and could selectively stain nuclei in living cells.

A Tris(hydroxymethyl)aminomethane‐Rhodamine Spirolactam Derivative as Dual Channel pH and Water Sensor and Its Application to Bio Imaging

“…This shows that R1 has good cell membrane permeability and also indicates that R1 has appropriate size of the planar aromatic system, hydrophilicity and base strength to act as a nuclear staining agent. Similar examples have already been documented in the literature 22,23…”

Charge-driven tripod somersault on DNA for ratiometric fluorescence imaging of small molecules in the nucleus

“…Moreover, although the ratiometric uorescence sensing of these bioactive molecules in the whole cell, cytoplasm, and mitochondria has been widely explored, 19,31,32 it is still a challenging task to trace their ux in the nucleus. Indeed, the rare examples only include nuclearlocalized probes NucPE1, SNAP-PG and a highly sensitive probe NP1 responding to the changes of nuclear H 2 O 2 uxes, [33][34][35] a photo-stable pH probe NaOCy and a ratiometric uorescence pH probe hoeFL for selectively staining nuclei in living cells; 36,37 a sulfur-containing uorogenic probe JG45 for selectively detecting nuclear methylmercury (MeHg 2+ ). 38 The difficulty in visualizing the ux of bioactive molecules in the nucleus is mainly due to the impermeable nuclear membrane and the interference of the complex nucleic acid environment with the uorescence of probes.…”

Novel Rhodamine B and 2H‐benzo[b][1,4]oxazin‐3(4H)‐one‐derived Fluorescent Sensor for Low pH Value Detection

“…Fluorescent analysis is recognized as a convenient and highly sensitive technique for the detection of pH values and has been proven to be one of the best methods for the analysis of trace biological compounds in complex biological samples . Compared with other detection methods, the noninvasive fluorescent probes have advantages such as high selectivity and the ability for real‐time detection . There are numerous classes of fluorescent sensors .…”