Development of triphenylamine functional dye for selective photoelectrochemical sensing of cysteine.
A novel triphenylamine-based organic dye, TTA, with an acrylic group is designed to graft TiO2 nanoparticles for sensitive and selective photoelectrochemical sensing. The synthesized TTA possesses a high molar absorption coefficient, leading to an enhanced photoelectron emission ability of the electron donor. The carboxyl group of TTA acts as not only an electron acceptor but also a linker to connect TTA to TiO2 nanoparticles. Under irradiation, TTA shows fast intramolecular charge transfer from triphenylamine to carboxyl group via the π-bridge of thiophene moiety, thus producing a sensitive photocurrent response. Meanwhile, the acrylic moiety provides an active site for the Michael addition reaction, which would destroy the π-bridge and decrease the photocurrent response. Thus, a selective photoelectrochemical sensing strategy is proposed for detection of small biomolecules. Using cysteine as a model analyte, this sensing strategy shows a detectable range from 1 to 200 μM, without the interference from natural amino acids and various biological reducing reagents. This work offers a new photoelectrochemical route to highly selective and sensitive detection of biologically important small molecules.
School of Chemistry, Dalian University of Technology , Dalian 116023, PR China.
Shuo
S
Wu
Honglei
H
Song
Jie
J
Song
Cheng
C
He
Jun
J
Ni
Yanqiu
Y
Zhao
Xiuyun
X
Wang
D000814:Aniline Compounds / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D003545:Cysteine / Q000032:analysis*; D055664:Electrochemical Techniques / Q000379:methods*; D055668:Photochemical Processes; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
D000814:Aniline Compounds; D004396:Coloring Agents; D003545:Cysteine