Biosensors and Bioelectronics: X (Sep 2022)
Design of EQCM-MIP sensing matrix for highly specific and sensitive detection of thyroglobulin
Abstract
In this paper an electrochemical quartz crystal microbalance (EQCM)-MIP sensor for thyroglobulin had been developed by using 4-aminothiophenol (4-ATP) - methacrylic acid (MAA)- reduced graphene oxide (RGO) composite as a polymeric format for the first time. Thyroglobulin plays a central role in the biology of thyroid as active and exclusive support for thyroid hormone synthesis and storage. Measurement of serum thyroglobulin is primarily used to detect recurrence of follicular thyroid cancer following total thyroidectomy and radioactive iodine ablation. The MIP sensor was developed by electodeposition of 4-ATP-MAA-RGO composite on EQCM electrode in presence of template thyroglobulin. Due to the location of imprinted sites on the surface and high specific surface area, analyte molecules have good accessibility and high binding affinity to template molecules thus yielding a highly sensitive and efficient signal. The limit of detection of 0.02 ng/mL, without any crossreactivity and matrix effect indicates high sensitivity and selectivity for thyroglobulin. The sensor was appreciably selective to thyroglobulin in presence of probable interferents. The relative standard deviation for determination was 4.23%. Based on speediness and sensitivity, the sensor is reusable and shows a great improvement in selectivity and adsorption capacity over other sensors.
