resumo
A surface plasmon resonance (SPR) phenomenon implemented via D-shaped polymer optical fiber (POF) is exploited to realize cortisol biosensors. In this work, two immonosensors are designed and developed for the qualitative as well as quantitative measurement of cortisol in artificial and real samples. The performances of the POF-based biosensors in cortisol recognition are achieved using different functionalization protocols to make the same antibody receptor layer over the SPR surface via cysteamine and lipoic acid, achieving a limit of detection (LOD) of 0.8 pg/mL and 0.2 pg/mL, respectively. More specifically, the use of cysteamine or lipoic acid changes the distance between the receptor layer and the SPR surface, improving the sensitivity at low concentrations of about one order of magnitude in the configuration based on lipoic acid. The LODs of both cortisol biosensors are achieved well competitively with other sensor systems but without the need for amplification or sample treatments. In order to obtain the selectivity tests, cholesterol and testosterone were used as interfering substances. Moreover, tests in simulated seawater were performed for the same cortisol concentration range achieved in buffer solution to assess the immunosensor response to the complex matrix. Finally, the developed cortisol biosensor was used in a real seawater sample to estimate the cortisol concentration value. The gold standard method has confirmed the estimated cortisol concentration value in real seawater samples. Liquid-liquid extraction was implemented to maximize the response of cortisol in liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis.
palavras-chave
OPTICAL-FIBER; STRESS; SPR; IMMUNOSENSOR; RESPONSES; WATER
categoria
Science & Technology - Other Topics
autores
Arcadio, F; Soares, S; Nedoma, J; Aguiar, D; Pereira, AC; Zeni, L; Cennamo, N; Marques, C
nossos autores
Carlos Marques
Professor AuxiliarProjectos
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
agradecimentos
F.A, N.C. and L.Z. acknowledge the support of the European Union by the Next Generation EU project PRIN2022-2022JRKETK-"BOHEMIAN" (Versatile hybrid in-fiBer OpticalelectrocHemical systEMs for wIdely Applicable bioseNsing). All authors acknowledge the Fundac & atilde;o para a Ciencia e a Tecnologia (UI/BD/153066/2022); Fundac & atilde;o para a Ciencia e a Tecnologia/Ministerio da Educac & atilde;o e Ciencia (PTDC/EEI-EEE/0415/2021, LA/P/0006/2020, UIDB/50011/2020, UIDP/50011/2020, LA/P/0037/2020, UIDB/50025/2020, UIDP/50025/2020). The research was co-funded by the financial support of the European Union under the REFRESH-Research Excellence For REgion Sustainability and High-tech Industries project number CZ.10.03.01/00/22_003/0000048 via the Operational Programme Just Transition. This work was also supported by the Ministry of Education, Youth, and Sports of the Czech Republic conducted by the VSB-Technical University of Ostrava, under Grant No. SP2024/081.