Electrochemical Biosensors

November 7, 2014 13:15 PSP Book - 9in x 6in 12-Serge-Cosnier-c12

ECL Biosensor and Its Applications 357

electrochemical oxidation inhibition mechanism [83]. The presence

of these compounds produces a larger IR drop and makes the

practical potential E

w

less than the applied potential E [84]:

E

w

= E − IR = E − (I

q

+ I

emitter

)R (12.42)

where I

q

and I

emitter

are the oxidation currents of the quencher

and the light emitterm respectively. The lower E

w

decreases the

oxidation of the light emitter, leading to weaker ECL emission. Thus

after addition of nitrite to the detection solution, the ECL of the CdSe

QDs/sulfite system at +0.927 V was attenuated, which leads