"On-off-on" switchable sensor: a fluorescent spiropyran responds to extreme pH conditions and its bioimaging applications.
A novel spiropyran that responds to both extreme acid and extreme alkali and has an "on-off-on" switch is reported. Benzoic acid at the indole N-position and carboxyl group at the indole 6-position contribute to the extreme acid response. The ionizations of carboxyl and phenolic hydroxyl groups cause the extreme alkali response. Moreover, the fluorescent imaging in bacterial cells under extreme pH conditions supports the mechanism of pH response.
State Key Laboratory of Chemical Resource Engineering, Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology , Beijing 100029, China.
Shulin
S
Wan
Yang
Y
Zheng
Jie
J
Shen
Wantai
W
Yang
Meizhen
M
Yin
D001578:Benzopyrans / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007211:Indoles / Q000737:chemistry*; D057054:Molecular Imaging / Q000379:methods*; D009574:Nitro Compounds / Q000737:chemistry*
D001578:Benzopyrans; D004396:Coloring Agents; D005456:Fluorescent Dyes; D007211:Indoles; D009574:Nitro Compounds; C088184:spiropyran; C030374:indole
bacterial labeling; chromophores; dual color; extreme pH sensor; spiropyran; “on−off−on” switch