A new turn-on fluorescent chemosensor based on diketopyrrolopyrrole (DPP) for imaging Zn2+ in living cells

Abstract

A new turn-on fluorescent chemosensor, DPPL1, was rationally designed and synthesized based on diketopyrrolopyrrole (DPP), which presented high sensitivity and selectivity for Zn(2+). Specifically, DPPL1 presented a large emission enhancement and a 70 nm blue-shift upon Zn(2+) binding. (1)H NMR titrations, studies into the pH effects and DFT calculations further proved that this phenomenon was due to both photo-induced electron transfer (PET) and intra-molecular charge transfer (ICT) processes. More importantly, DPPL1 was successfully used for imaging Zn(2+) in living HeLa cells. To the best of our knowledge, this is the first DPP-based fluorescent chemosensor to recognize Zn(2+) ions in living cells with a large blue-shift and a fluorescent enhancement based on both photo-induced electron-transfer (PET) and intramolecular charge-transfer (ICT) effects. Meanwhile, we have also provided a new effective platform for the development of fluorescent chemosensors for other analytes.

Diketopyrrolopyrroles: Synthesis, Reactivity, and Optical Properties

“…The acidifi cation of the solution of compound 154 also turns on the fl uorescence due to the protonation of amine groups. [ 99 ] Similar results were obtained when amine groups were exchanged into the analogous tertiary amide functions. [ 100 ] Compound 154 can be used for the detection of zinc ions inside living cells in fl uorescence microscopy.…”

“…An example of such a DPP-based derivative is dye 154 ( Scheme 51 ). [ 99 ] In the free-base form, this compound shows very weak fl uorescence, which is caused by photoinduced electron transfer (PET) in the excited state from the electron-rich amine groups to the electron-poor DPP core. Due to the presence of dipicolylamine subunits, dye 154 is capable of strong complexation of zinc cations.…”

“…[ 100 ] Compound 154 can be used for the detection of zinc ions inside living cells in fl uorescence microscopy. [ 99 ] DPP 156 , which was obtained by the condensation of the corresponding diformyl DPP with malononitrile, turned out to be a very good fl uorescent sensor for thiols. [ 101 ] The authors demonstrated that 156 dissolved in a mixture of acetonitrile and water reacts with cysteine, giving a Michael diadduct 157 ( Scheme 52 ).…”

A highly sensitive benzimidazole-based chemosensor for the colorimetric detection of Fe(ii) and Fe(iii) and the fluorometric detection of Zn(ii) in aqueous media

“…12,13 In human body zinc is the second most abundant element aer iron. [17][18][19][20] However, excessive Zn 2+ ion would cause imbalance in cellular processes, resulting in neurodegenerative diseases such as Menkes and Wilson diseases, Alzheimer's disease, Parkinson's disease, prostate cancer and diabetes. [17][18][19][20] However, excessive Zn 2+ ion would cause imbalance in cellular processes, resulting in neurodegenerative diseases such as Menkes and Wilson diseases, Alzheimer's disease, Parkinson's disease, prostate cancer and diabetes.…”

Diketopyrrolopyrrole-based chemosensors for selective recognition of fluoride ions

“…19 Recently, many research groups reported progress in the development of DPP-containing fluorescent sensors, and they investigated their applications in selective detection of thiols, Zn 2+ , cyanide, pH, DNA and CO 2 . [20][21][22][23][24][25][26] However, reports on the F -detection using DPP derivatives were very few. [27][28][29][30][31] Present study was a part of our current research interest towards chemosensors based on DPP with hydrazone (-CH=N-NH-) as bridge.…”