Cysteinehydropersulfide (Cys-SSH) plays primary roles in synthesis of sulfur containingcofactors, regulation of cellular signaling, activation or inactivation ofenzyme activities, and modulation of cellular redox milieu. However, itsbiofunctions need to be further addressed due to the fact that many issuesremain to be clarified. Herein, we conceive a novel ratiometric near-infrared fluorescentprobe Cy-Dise for the sensitive andselective detection of Cys-SSH in living cells and in vivo for the first time. Cy-Diseis composed of three moieties: bis(2-hydroxyethyl) diselenide, heptamethinecyanine, and D-galactose. Cy-Diseexhibits satisfactory linear ratio response to Cys-SSH via selenium-sulfurexchange reaction in the range of 0 - 12 μM Cys-SSH. The experimental detectionlimit is determined to be 0.12 μM. The results of ratio imaging analysesconfirm the qualitative and quantitative detection capabilities of Cy-Dise in HepG2 cells, HL-7702 cells,and primary hepatocytes. The level changes of Cys-SSH in cells stimulated by some related reagents are also observed. The probe isalso suitable for deep tissue ratio imaging. Organ targeting tests with Cy-Dise in normal Spraque-Dawley (SD)rats and Walker-256 tumor SD rats verify its predominant localization in liver.The probe is promising for revealing the roles of Cys-SSH in physiological andpathological processes.

同行评议：I have read the whole manuscript with a lot ofinterest. On balance this is a very important study. The bio-medicalexperiments were excellent and push boundaries of how this type ofresearch/papers that describe a new probe should be done.

Quantificationof cysteine hydropersulfide with a ratiometric near-infrared fluorescent probebased on selenium-sulfur exchange reaction

Xiaoyue Han,^ab†Fabiao Yu,^a† Xinyu Song,^a Lingxin Chen^a*

Chemical Science, 2016, DOI: 10.1039/C6SC00838K

http://pubs.rsc.org/en/content/articlelanding/2016/sc/c6sc00838k