title: Enzymatic Hydrogelation-Induced Fluorescence Turn-Off for Sensing Alkaline Phosphatase in Vitro and in Living Cells.
abstract: Alkaline phosphatase (ALP)-catalyzed hydrogelation has been extensively explored and found wide applications. Spectroscopic and electrochemical approaches are commonly employed for the detection of ALP activity. Herein, by rational design of a fluorescence probe Fmoc-K(FITC)FFYp (P1) (where FITC is fluorescein), we incorporated sol-gel transition with fluorescence "turn-off" and developed a new method for quantitative sensing ALP activity in vitro and in living cells. Under the catalysis of ALP, P1 was converted to hydrogelator Fmoc-K(FITC)FFY (1) which self-assembles into nanofibers to form Gel I. Accompanying this sol-gel transition, the fluorescence emission of P1 was turned off. Our assay was employed to detect ALP activity over the range of 0-2.8 U/mL with a limit of detection (LOD) of 0.06 U/mL. ALP-inhibitor-treated cell imaging indicated that P1 could be applied for sensing ALP activity in living cells. Our method provides a new option for real time and quantitative sensing ALP activity in vitro and even in living cells.
authors.affiliation: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.|‡Department of Chemistry and Chemical Engineering, Hefei Normal University, Hefei, Anhui 230061, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Dong
authors.affiliation: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Miao
authors.affiliation: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Zijuan
authors.initials: Z
authors.lastname: Hai
authors.affiliation: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Gaolin
authors.initials: G
authors.lastname: Liang
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis*; D019793:Fluorescein / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry*; D066298:In Vitro Techniques; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D020100:Hydrogels; D000469:Alkaline Phosphatase; D019793:Fluorescein