Cobalt ion-mediated cysteine detection with a hyperbranched conjugated polyelectrolyte as a new sensing platform.
A highly efficient colorimetric and fluorescence turn-off probe for the sensitive and selective detection of the biologically important amino acid, cysteine (Cys), is demonstrated using a newly synthesized water-soluble hyperbranched polymer (HP) containing sulfonic acid groups. The detection mechanism involves two steps: (i) the slight quenching of HP in the presence of Co(2+)  in advance; and (ii) the gradual quenching of the HP-Co(2+)  complex according to the concentration of Cys due to the absorption screening effect of the formation of the Cys-Co(2+)  complex, which prevents HP from absorbing excitation energy.
Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon, Korea.
Daigeun
D
Kim
Geunseok
G
Jang
Jongho
J
Kim
Seongwon
S
Seo
Won Ho
WH
Park
Taek Seung
TS
Lee
D015374:Biosensing Techniques / Q000295:instrumentation*; D003035:Cobalt / Q000737:chemistry*; D003545:Cysteine / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*
D004573:Electrolytes; D007477:Ions; D011108:Polymers; D003035:Cobalt; D003545:Cysteine