Highly sensitive and selective turn-on fluorescent and chromogenic probe for Cu²⁺and ClO⁻based on a N-picolinyl rhodamine B-hydrazide derivative

Abstract

A new rhodamine B-based dual-function chromo- and fluorogenic probe for Cu(2+) and ClO(-) has been designed, synthesized, and characterized. The probe comprises a spectroscopic unit of rhodamine B and a Cu(2+)-specific chelating unit of pyridinecarboxamide as well as a ClO(-)-specific reactive moiety of diacylhydrazine, and is a highly selective and extremely sensitive fluorescent and colorimetric sensor for Cu(2+) and ClO(-) in different pH conditions. Compared with the reported probes for Cu(2+) or ClO(-), this is the first chemosensor based on a small molecule that can detect both Cu(2+) and ClO(-), respectively, at 1 nM level.

“Off-On” based fluorescent chemosensor for Cu2+ in aqueous media and living cells

“…All the methods present good selectivity for Cu 2+ with signal enhancement, and most of them can adopt dual chromo-and fluorogenic changes toward Cu 2+ [11,[16][17][18][19], as well as our proposed NRC. A few of chemosensors possess wide quantitation span [11,17,18,21], or down to nM LOD [17,18], but some of them need more rigorous testing media and the applicability in living cells are not investigated.…”

“…All the methods present good selectivity for Cu 2+ with signal enhancement, and most of them can adopt dual chromo-and fluorogenic changes toward Cu 2+ [11,[16][17][18][19], as well as our proposed NRC. A few of chemosensors possess wide quantitation span [11,17,18,21], or down to nM LOD [17,18], but some of them need more rigorous testing media and the applicability in living cells are not investigated. Notably, as for the two types of enhancement chemosensors based on rhodamine [18] and naphthalimide modified rhodamine derivatives [11], dual-function detection for Cu 2+ and ClO − [18], and dual-function detection for Cu 2+ and Zn 2+ [11] are realized, respectively, however, their applications in living cells are not validated, yet.…”

“…A few of chemosensors possess wide quantitation span [11,17,18,21], or down to nM LOD [17,18], but some of them need more rigorous testing media and the applicability in living cells are not investigated. Notably, as for the two types of enhancement chemosensors based on rhodamine [18] and naphthalimide modified rhodamine derivatives [11], dual-function detection for Cu 2+ and ClO − [18], and dual-function detection for Cu 2+ and Zn 2+ [11] are realized, respectively, however, their applications in living cells are not validated, yet. Our newly developed chemosensor presents a number of attractive analytical features such as high sensitivity, wide linear range, good reproducibility, good selectivity and wide applicability.…”

Fluorescent probe for copper(II) ion based on a rhodamine spirolactame derivative, and its application to fluorescent imaging in living cells

“…Most of the fluorescence enhancement methods possess wide quantitation span [11,[22][23][24][25], but some of them have more or less disadvantages, such as irreversibility [11,25], complicated purification [22,23], and long analysis time [11]. As for the two types of enhancement probes based on rhodamine derivative, dual-function detection for Cu 2+ and ClO -are realized [28] and reversible response in living cells are exhibited [29], however, low yields still restrict their further applications [28,29]. Our newly developed fluorescence enhancement method presents a number of attractive analytical features such as high sensitivity, wide linear range, good reversibility and reproducibility, good selectivity, high yield and wide applicability.…”

“…On the basis of the spirolactam (non fluorescent) to ring-open amide (fluorescent) equilibrium of rhodamine, most of rhodamine fluorescent probes based on rhodamine hydrazide derivatives or rhodamine amine conjugates for various cations via chromogenical and fluorogenical signals have been successfully fabricated as the fluorescence enhancement type [26][27][28][29]. To date, many investigations are still in progress to search for cheaper, more stable, convenient and effective rhodamine derivatives.…”