A novel pyrene based fluorescent probe for selective detection of cysteine in presence of other bio-thiols in living cells

作者：Rani B Kirthika; John S Abraham^*

来源：Biosensors and Bioelectronics, 2016, 83: 237-242.

DOI：10.1016/j.bios.2016.04.013

• Pyrene based fluorescent probe
• Cysteine
• Spectrofluorimetry
• Intramolecular charge transfer
• Confocal microscopy
• HeLa cells

This manuscript reports the synthesis of pyrene-based fluorescent probe (PA-1) containing a,(3-unsaturated carbonyl moiety and its application towards the selective and sensitive detection of cysteine (Cys) over other bio-thiols. The probe, 3-(32-hydroxyphenyl)-1-pyrenyl-2-propenone (PA-1) was synthesized through Claisen-Schmidt condensation between acetyl pyrene and salicylaldehyde. The formed product was characterized by H-1 NMR, C-13 NMR and GC-MS techniques. The probe exhibited absorption maximum at 374 nm and emission maximum at 467 nm (lambda(ex)=342 nm). The emission intensity of PA-1 was greatly enhanced while adding 2.5 nM Cys. This can be attributed to the nucleophilic attack of Cys to the alpha,beta-unsaturated ketone resulting in switching off, intramolecular charge transfer (ICT) from pyrene moiety to the phenolic nucleus. This was confirmed by DFT measurements. The PA-1 exhibited an excellent selectivity towards the determination of 40 nM cys in the presence of 250,000-fold higher concentration of common interferents. The emission intensity was linearly increased and the limit of detection was found to be 10 pM/L (S/N=3). Interestingly, the response of the PA-1 towards Cys is less than 1 min. The confocal laser scanning micrographs of HeLa cells confirmed the cell permeability of the PA-1 and its ability to selectively detect Cys in living cells. In addition, the proposed probe was successfully applied for the determination of Cys in blood serum samples.

• 出版日期2016-9-15