Abstract
The development of a fully automated flow electrochemical aptasensor based on the use of a selective capture aptamer and modified magnetic beads (MBs) is reported. The developed flow-based aptasensor is demonstrated under continuous/stopped flow conditions for the detection of ochratoxin A (OTA) employing direct and indirect competitive strategies. In the direct format, biotin labeled and free OTA competed to bind with immobilized aptamer onto the surface of a screen printed carbon electrode (SPCE) placed in a flow cell. In the indirect assay, immobilized OTA and free OTA in solution competed to bind with aptamer in solution. The current response obtained from the conversion of the substrate 1-naphtyl phosphate by ALP decreased proportionally to the concentration of OTA in the sample. A lower limit of detection (0.05 μg/L) was obtained with the indirect flow-based aptasensor. Finally, the flow-based aptasensor was validated with real beer samples, and the good recovery values demonstrated the efficiency of the competitive aptasensor.
Original language | English |
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Pages (from-to) | 1160-1166 |
Number of pages | 7 |
Journal | Sensors and Actuators, B: Chemical |
Volume | 176 |
DOIs | |
State | Published - 2013 |
Externally published | Yes |
Keywords
- Beer sample
- Flow-based aptasensor
- Ochratoxin A
- On-line detection