Ortega, Francisco GabrielGomez, German EGonzalez-Martinez, CoralValero, TeresaExposito-Hernandez, JosePuche, IgnacioRodriguez-Martinez, AlbaSerrano, Maria JoseLorente, Jose AntonioFernandez-Baldo, Martin A2023-05-032023-05-032022-09-06Ortega FG, Gómez GE, González-Martinez C, Valero T, Expósito-Hernández J, Puche I, et al. A Novel, Quick, and Reliable Smartphone-Based Method for Serum PSA Quantification: Original Design of a Portable Microfluidic Immunosensor-Based System. Cancers (Basel). 2022 Sep 16;14(18):4483.2072-6694http://hdl.handle.net/10668/20917We describe a versatile, portable, and simple platform that includes a microfluidic electrochemical immunosensor for prostate-specific antigen (PSA) detection. It is based on the covalent immobilization of the anti-PSA monoclonal antibody on magnetic microbeads retained in the central channel of a microfluidic device. Image flow cytometry and scanning electron microscopy were used to characterize the magnetic microbeads. A direct sandwich immunoassay (with horseradish peroxidase-conjugated PSA antibody) served to quantify the cancer biomarker in serum samples. The enzymatic product was detected at -100 mV by amperometry on sputtered thin-film electrodes. Electrochemical reaction produced a current proportional to the PSA level, with a linear range from 10 pg mL-1 to 1500 pg mL-1. The sensitivity was demonstrated by a detection limit of 2 pg mL-1 and the reproducibility by a coefficient of variation of 6.16%. The clinical performance of this platform was tested in serum samples from patients with prostate cancer (PCa), observing high specificity and full correlation with gold standard determinations. In conclusion, this analytical platform is a promising tool for measuring PSA levels in patients with PCa, offering a high sensitivity and reduced variability. The small platform size and low cost of this quantitative methodology support its suitability for the fast and sensitive analysis of PSA and other circulating biomarkers in patients. Further research is warranted to verify these findings and explore its potential application at all healthcare levels.enAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/PSAcancer biomarkercancer diagnosisliquid biopsymagnetic microbeadsmicrofluidic immunosensorHumansProstate-Specific AntigenBiomarkers, TumorImmunoassayMicrospheresFlow CytometryMicrofluidicsBiosensing TechniquesLimit of DetectionMicroscopy, Electron, ScanningHorseradish PeroxidaseReproducibility of ResultsReproducibility of ResultsProstatic NeoplasmsDelivery of Health CareLab-On-A-Chip DevicesElectrodesAntibodies, MonoclonalMagnetic Phenomenaresearch article36139646open accessAnticuerpos monoclonalesAntígeno prostático específicoAtención a la saludBiomarcadores de tumorCitometría de flujoDispositivos laboratorio en un ChipElectrodosFenómenos magnéticosHumanosInmunoensayoLímite de detecciónMasculinoMicroesferasMicrofluídicaMicroscopía electrónica de rastreoNeoplasias de la próstataPeroxidasa de rábano silvestreReproducibilidad de los resultadosTécnicas biosensibles10.3390/cancers14184483PMC9496945https://www.mdpi.com/2072-6694/14/18/4483/pdf?version=1663316257https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9496945/pdf