Electrochemical biosensing of non-electroactive targets using ferrocene-labeled magnetic particles and CNT wiring.
We show that target binding onto ferrocene-modified magnetic microparticles (MP-Fc) promotes physical sheltering of the labels. This can be measured electrochemically by CNT wiring, which enhances ten-fold the signals registered compared to direct detection of the MPs alone. As a proof of concept, detection of detergents and antibodies is accomplished. In these preliminary experiments, random binding of 0.01% Tween 20 onto MP-Fc was detectable both voltametrically and impedimetrically after a 2 min incubation. Furthermore, affinity capture of 4 μg mL(-1) of biotinylated antibody by streptavidin MP-Fc could be measured in less than 30 min and even in the presence of 1 mg mL(-1) of BSA.
IK4-Ikerlan Technological Research Centre, 20500 Mondragón, Spain.
Zorione
Z
Herrasti
Rosa
R
Olivé-Monllau
Francesc Xavier
FX
Muñoz-Pascual
Fernando
F
Martínez
Eva
E
Baldrich
D000906:Antibodies / Q000032:analysis; D015374:Biosensing Techniques / Q000295:instrumentation*; D019921:Biotinylation; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004867:Equipment Design; D005296:Ferrous Compounds / Q000737:chemistry*; D059346:Magnets / Q000737:chemistry*; D000075163:Metallocenes; D011136:Polysorbates / Q000032:analysis
D000906:Antibodies; D005296:Ferrous Compounds; D000075163:Metallocenes; D011136:Polysorbates; C004998:ferrocene