TY - JOUR
T1 - Label-free aptasensor for lysozyme detection using electrochemical impedance spectroscopy
AU - Ortiz-Aguayo, Dionisia
AU - del Valle, Manel
PY - 2018/2/1
Y1 - 2018/2/1
N2 - © 2018 by the authors. This research develops a label-free aptamer biosensor (aptasensor) based on graphite-epoxy composite electrodes (GECs) for the detection of lysozyme protein using Electrochemical Impedance Spectroscopy (EIS) technique. The chosen immobilization technique was based on covalent bonding using carbodiimide chemistry; for this purpose, carboxylic moieties were first generated on the graphite by electrochemical grafting. The detection was performed using [Fe(CN) 6 ] 3- /[Fe(CN) 6 ] 4- as redox probe. After recording the frequency response, values were fitted to its electric model using the principle of equivalent circuits. The aptasensor showed a linear response up to 5 µMfor lysozyme and a limit of detection of 1.67 µM. The sensitivity of the established method was 0.090 µM -1 in relative charge transfer resistance values. The interference response by main proteins, such as bovine serum albumin and cytochrome c, has been also characterized. To finally verify the performance of the developed aptasensor, it was applied to wine analysis.
AB - © 2018 by the authors. This research develops a label-free aptamer biosensor (aptasensor) based on graphite-epoxy composite electrodes (GECs) for the detection of lysozyme protein using Electrochemical Impedance Spectroscopy (EIS) technique. The chosen immobilization technique was based on covalent bonding using carbodiimide chemistry; for this purpose, carboxylic moieties were first generated on the graphite by electrochemical grafting. The detection was performed using [Fe(CN) 6 ] 3- /[Fe(CN) 6 ] 4- as redox probe. After recording the frequency response, values were fitted to its electric model using the principle of equivalent circuits. The aptasensor showed a linear response up to 5 µMfor lysozyme and a limit of detection of 1.67 µM. The sensitivity of the established method was 0.090 µM -1 in relative charge transfer resistance values. The interference response by main proteins, such as bovine serum albumin and cytochrome c, has been also characterized. To finally verify the performance of the developed aptasensor, it was applied to wine analysis.
KW - Aptamer
KW - Biosensor
KW - Electrochemical grafting
KW - Electrochemical impedance spectroscopy
UR - https://ddd.uab.cat/record/199392
U2 - https://doi.org/10.3390/s18020354
DO - https://doi.org/10.3390/s18020354
M3 - Article
VL - 18
JO - Sensors
JF - Sensors
SN - 1424-3210
IS - 2
M1 - 354
ER -