A Fluorescent Probe for Selective Facile Detection of H₂S in Serum Based on an Albumin-Binding Fluorophore and Effective Masking Reagent

Abstract

A fluorescent probe (4-(2-(4-(diethylamino)phenyl)-4-methyl-5-oxo-4,5-dihydrothieno[3,2- b ]pyridin-7-yl)phenyl 2,4-dinitrobenzenesulfonate, KF-DNBS ) for facile detection of H 2 S in serum was developed based on the combination of an environment-sensitive fluorophore (2-(4-(diethylamino)phenyl)-7-(4-hydroxyphenyl)-4-methylthieno[3,2- b ]pyridin-5(4 H )-one, KF ) with albumin and the 2,4-dinitrobenzene sulfonyl (DNBS) group as a recognition unit for H 2 S. KF-DNBS showed remarkable fluorescence enhancement due to H 2 S-triggered thiolysis followed by the formation of a fluorescent fluorophore ( KF )-albumin complex. The H 2 S detection limit of KF-DNBS was estimated to be 3.2 μM, and KF-DNBS achieves a high selectivity to H 2 S over biothiols by employing 2-formyl benzene boronic acid (2-FBBA) as an effective masking reagent. Furthermore, under optimized sensing conditions, KF-DNBS could be applied to accurately determine spiked H 2 S in human serum without the need for any further procedure for the removal of serum proteins.

Activity-Based Fluorescent Probes for Hydrogen Sulfide and Related Reactive Sulfur Species

“…The turnon response to H 2 S was also demonstrated in HADF cells treated with exogenous H 2 S. Lee and Han reported 475 (KF-DNBS) based on H 2 S-medaited cleavage of the DNBS group to release the KF fluorophore that is only weakly fluorescent unless complexed to human serum albumin (HSA). 500 This probe showed poor selectivity for H 2 S over Cys or Hcy unless the samples were also treated with 2-formyl benzene boronic acid to scavenge the Cys and Hcy present in solution. Also using a benzothiazole motif, Li reported 476, which provided a turn-on response at 479 nm and was further used to develop H 2 S responsive test strips.…”

Small Molecule Optical Probes for Detection of H2S in Water Samples: A Review

“…The probes are categorized into two based on the detection mechanism: (i) “reactive” probes that work on irreversible S 2– -specific chemical reactions centered on the double nucleophilic nature and reduction ability of H 2 S and (ii) “competitive” probes that utilize displacement of metal ions to selectively react with H 2 S and not with any other sulfur containing species or anions. Nitro, hydroxylamine, azide, − DNP ethers, − nitrobenzoxadiazole (NBO) ether, , and NBD − are the copiously used functional groups for the colorimetric detection of H 2 S.…”

A Highly Selective and Sensitive Colorimetric Chemosensor for the Detection of Hydrogen Sulfide: A Real‐time Application in Multiple platforms

“…Chemodosimeter is the most common optical approach in which the chemical probe is incorporated with an H 2 S selective irreversible responsive unit and optical response modulator. Functional groups such as nitro (39–41), azide (42–48), hydroxylamine (49) (H 2 S induced reduction), dinitrophenyl ethers (50–60), disulfide bonds (61), nitrobenzoxadiazole ether (62, 63) and nitrobenzofurazan (64–68) (NBD) (H 2 S induced hydrolysis) are the functional groups dexterously employed for the detection of H 2 S. As H 2 S has a strong binding affinity toward metal ions, its metal displacement or coordination has also been copiously used to detect H 2 S (69, 70). Though most of the optical techniques to detect H 2 S are based on fluorescence changes, visible color change of the probes in the presence of H 2 S is also often reported.…”