Development of an impedimetric sensor for the label-free detection of the amino acid sarcosine with molecularly imprinted polymer receptors

• Published in: Sensors and actuators. B, Chemical Chemical, 2017-07, Vol.246, p.461-470
• Main Authors: Nguy, Tin Phan, Van Phi, Toan, Tram, Do T.N., Eersels, Kasper, Wagner, Patrick, Lien, Truong T.N.
• Format: Article
• Language: English
• Subjects: Faradaic electro-chemical Impedance spectroscopy EIS; Gold nanoparticles; Molecularly imprinted polymers; Prostate cancer; Sarcosine
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.02.101

[Display omitted] •AuNPs were scattered on SPCE by CV method•AuNPs/SPCE is sensitive transducing platform for sarcosine-MIP impedimetric sensor.•The sophisticated thickness of MIP was confirmed to be created on AuNPs/SPCE platform.•Sarcosine was removed from MIP film by electroelution method.•The sensor has LOD to be 0.84ng/mL in a linear range from 1ng/mL to 1.6μg/mL. In this article we report on the development and optimization of a biomimetic sensor for the label-free detection of the amino acid sarcosine, a molecule which is seen as a biomarker for prostate cancer. The recognition elements were sarcosine-imprinted poly-aminothiophenol (p-ATP) layers deposited by electro-polymerization onto screen-printed gold electrodes and, for comparison, onto carbon electrodes covered first with a gold-nanoparticles interlayer. Using the latter type of electrodes, we reached a detection limit below 1nM in aqueous buffer solutions with an accessible concentration range from the nano- to the micromolar scale. This was achieved by a careful thickness optimization of the Au-nanoparticle and the p-ATP layers in combination with Faradaic impedance spectroscopy as a readout method. The sensor showed an excellent reproducibility, a good stability with time, and a surprisingly low cross-selectivity towards other proteins.