A highly reusable genosensor for late-life depression diagnosis based on microRNA 184 attomolar detection in human plasma

• Published in: Talanta (Oxford) Vol. 258; p. 124342
• Main Authors: Guedes, Pedro H.G., Brussasco, Jéssica G., Moço, Anna C.R., Moraes, Dayane D., Segatto, Monica, Flauzino, José M.R., Mendes-Silva, Ana P., Vieira, Carlos U., Madurro, João M., Brito-Madurro, Ana G.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2023
• Subjects: Aged; Biomarkers; Biosensing Techniques - methods; biosensors; Depression - diagnosis; Depression - genetics; detection limit; dielectric spectroscopy; elderly; Electrochemical genosensor; Electrochemical Techniques - methods; electrochemistry; ethidium; Gene Expression Regulation; Humans; Late-life depression; microRNA; MicroRNAs; miR-184 detection; oxidation; voltammetry; Electrochemical genosensor; microRNA; Depression diagnosis; miR-184 detection; Late-life depression
• ISSN: 0039-9140; 1873-3573; 1873-3573
• DOI: 10.1016/j.talanta.2023.124342

Late-Life Depression (LLD) is one of the most prevalent psychiatric disorders in elderly, causing significant functional impairments. MicroRNAs are small molecules involved in the post-transcriptional regulation of gene expression. Elderly individuals diagnosed with LLD present down regulation of miR-184 (hsa-miR-184) expression compared to healthy patients. Therefore, this miR-184 can be used as a biomarker to diagnose LLD. Current LLD diagnosis depends primarily on clinical subjective identification, based on symptoms and variable scales. This work introduces a novel and facile approach for the LLD diagnosis based on the development of an electrochemical genosensor for miR-184 detection in plasma, using differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). DPV results presented a 2-Fold increase in current value for healthy patients, compared to individuals with LLD when monitoring ethidium bromide oxidation peak. For EIS, a 1.5-fold increase in charge transfer resistance for healthy elderly subjects was observed in comparison with depressed patients. In addition, the analytical performance of the biosensor was evaluated using DPV, obtaining a linear response ranging from 10−9 mol L−1 to 10−17 mol L−1 of miR-184 in plasma and a detection limit of 10 atomoles L−1. The biosensor presented reusability, selectivity and stability, the current response remained 72% up to 50 days of storage. Thus, the genosensor proved to be efficient in the diagnosis of LLD, as well as the accurate quantification of miR-184 in real plasma samples of healthy and depressed patients. •The first electrochemical genosensor for miR-184 detection is reported.•A facile and novel approach to diagnose Late-Life depression based on an electrochemical genosensor is proposed.•The biosensor presented an attomolar limit of detection, good stability, selectivity and a remarkable regeneration capability.•The genosensor was able to discriminate real biological samples from healthy and depressed elderly patients.