Browsing by Author "Correa-Duarte, Miguel A."
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- Amplified Sensitivity in SERS Detection of L1CAM With Silver Plasmonic Mesoporous Silica Capsules on an Imprinted FilmsPublication . Castaño-Guerrero, Yuselis; Arjones-Fernández, Belén; Moreira, Felismina T. C.; Alvarez-Puebla, Ramon A.; Correa-Duarte, Miguel A.; Águas, H.; Sales, M. Goreti F.This study presents a novel approach for dual detection, leveraging a combination of a Raman reporter-bearing nanomaterial and molecular imprinting polymers (MIP). A core-shell Au-Ag nanoparticles (Au-Ag NPs) encapsulated in mesoporous silica nanocapsules (Au-Ag NCs) and a new MIP-based material targeting L1CAM are used. The MIP prepared via surface imprinting on a carbon screen-printed electrode (C-SPE) used thionine (TH) as a monomer. The plasmonic Au-AgNCs are further functionalized with the Raman reporter 4-mercaptobenzoic acid (MBA) and anti-L1CAM for selective detection by surface-enhanced Raman scattering (SERS) spectroscopy. The biosensor's analytical performance is evaluated using both SERS and electrochemical impedance spectroscopy (EIS). EIS analysis reveals a linear response within the concentration range of 0.1 to 100 ng mL−1 in buffer and serum samples. SERS demonstrates a sensitivity ten times higher than EIS. Selectivity study demonstrates the biosensor's excellent specificity toward L1CAM, with minimal interference from other compounds such as creatinine, glucose, and carbohydrate antigen 19-9 (CA 19-9). The Raman signal from the reporter molecule correlates with increasing L1CAM concentrations, reinforcing the analytical findings obtained through electrochemical analysis. Thus, the combination of dual detection and recognition capabilities presents promising potential for detecting diverse biomarkers, especially in critical scenarios where reducing false-positive or false-negative errors is crucial.
- Application of gold nanoparticles as radiosensitizer for metastatic prostate cancer cell linesPublication . Soares, Sílvia; Faria, Isabel; Aires, Fátima; Monteiro, Armanda; Pinto, Gabriela; Sales, Maria Goreti; Correa-Duarte, Miguel A.; Guerreiro, Susana G.; Fernandes, RúbenMore than 50% of all prostate cancer (PCa) patients are treated by radiotherapy (RT). Radioresistance and cancer recurrence are two consequences of the therapy and are related to dose heterogeneity and non-selectivity between normal and tumoral cells. Gold nanoparticles (AuNPs) could be used as potential radiosensitizers to overcome these therapeutic limitations of RT. This study assessed the biological interaction of different morphologies of AuNPs with ionizing radiation (IR) in PCa cells. To achieve that aim, three different amine-pegylated AuNPs were synthesized with distinct sizes and shapes (spherical, AuNPsp-PEG, star, AuNPst-PEG, and rods, AuNPr-PEG) and viability, injury and colony assays were used to analyze their biological effect on PCa cells (PC3, DU145, and LNCaP) when submitted to the accumulative fraction of RT. The combinatory effect of AuNPs with IR decreased cell viability and increased apoptosis compared to cells treated only with IR or untreated cells. Additionally, our results showed an increase in the sensitization enhancement ratio by cells treated with AuNPs and IR, and this effect is cell line dependent. Our findings support that the design of AuNPs modulated their cellular behavior and suggested that AuNPs could improve the RT efficacy in PCa cells.
- Development of a biosensor for phosphorylated Tau 181 protein detection in Early-Stage Alzheimer’s diseasePublication . Schneider, Maria; Guillade, Lucía; Correa-Duarte, Miguel A.; Moreira, FelisminaAlzheimer's disease (AD) is the most common form of dementia in the elderly, and there are still no reliable methods for its early detection. Recently, the phosphorylated protein Tau181 (p-Tau181) was identified as a highly specific biomarker for AD. Therefore, in this work, a new strategy for the development of an electrochemical-based immunosensor for the detection of p-Tau181 is described. For this purpose, a carbon screen-printed electrode (C-SPE) was modified with platinum nanoparticles decorated with multi-walled carbon nanotubes (MWCNTs- PAH /Pt) to enable antibody binding. Scanning electron microscopy, transmission electron microscopy, Raman and X-ray photoelectron spectroscopy were used to study the morphology and crystallinity of the nanomaterials. Cyclic voltammetry and square-wave voltammetry were performed to compare the electrochemical properties of these electrodes. Under optimal conditions, the developed immunosensor exhibited a linear range from 8.6 to 1100 pg/mL, and the detection limit was estimated to be 0.24 pg/mL. This device showed excellent reproducibility and stability with remarkable selectivity for p-Tau181 in serum samples. Overall, this device enables minimally invasive clinical evaluation of p-Tau181 level with high sensitivity through simple operation, which makes this device a promising tool for future point-of-care purposes that will contribute to the technological development of clinical diagnostics.
- Development of a novel electrochemical biosensor based on plastic antibodies for detection of STEAP1 biomarker in cancerPublication . Carvalho, Margarida; Rocha, Sandra Moreira; Barroca-Ferreira, Jorge; Maia, Claudio J.; Guillade, Lucía; Correa-Duarte, Miguel A.; Passarinha, Luís A.; Moreira, Felismina T.C.; Gomes, Rui M.STEAP1 is a cell surface protein of the STEAP family whose main function focuses on intercellular communication and cell growth. STEAP1 is considered a promising putative biomarker and a candidate target for prostate cancer treatment. For specific and selective detection of STEAP1, a molecularly imprinted polymers (MIP) was developed on a screen-printed electrode (C-SPE) whose surface was modified with a nanocomposite based on carbon nanotubes decorated with dendritic platinum nanoparticles (CNTs- PAH /Pt). Then, the MIPs were produced on the modified C-SPE by electropolymerization of a mixture of STEAP1 and a monomer (pyrrole-2-carboxylic acid). Then, the protein was removed from the polymeric network by enzymatic treatment with trypsin, which created the specific template cavities for further STEAP1 detection. Electrochemical techniques such as EIS and CV were used to follow the chemical modification steps of C-SPE. The analytical performance of the biosensor was evaluated by SWV in PBS buffer and in lysates of neoplastic prostate cancer cells (LNCaP) extracts. The MIP material showing a linear range from 130 pg/ml to 13 µg/ml. Overall, the biosensor exhibits essential properties such as selectivity, sensitivity and reproducibility for its application in medical and clinical research diagnosis and/or prognosis of prostate cancer.
- SERS and electrochemical impedance spectroscopy immunoassay for carcinoembryonic antigenPublication . Castaño-Guerrero, Yuselis; Moreira, Felismina; Sousa-Castillo, Ana; Correa-Duarte, Miguel A.; Sales, GoretiThis work describes an innovative dual detection approach, combining electrochemical and surface-enhanced Raman scattering (SERS) sequential readings, on the same sensing surface. This was achieved by establishing (i) an antibody binding stage on a suitably modified screen-printed electrode (Au-SPE), to produce an electrochemical signalling system, followed by (ii) a second antibody binding stage, on the same sensing surface, comprising gold nanostars (AuNS) with a suitable Raman reporter, and acting as a second signalling system (SERS). This simple principle is applied herein to carcinoembryonic antigen (CEA) detection. The first layer of antibodies was assembled on the Au-SPE previously modified with a cysteamine layer. Binding to CEA was allowed for 30 minutes. Electrochemical impedance spectroscopy (EIS) readings followed the several stages of Au-SPE modification and generated analytical data. After, the AuNS were modified with 4-aminothiophenol (4-ATP)/Ab-CEA, and incubated on the same sensing surface, to provide SERS data. The analytical features were checked for both EIS and SERS. In EIS, the sensor showed linear response range from 0.25 to 250 ng/mL, with a linear correlation coefficient of 0.991, evaluated in serum. It also demonstrated good selectivity against creatinine and glucose. Using the SERS as signalling system, the spectra confirmed differentiated signals from the background within 0.025 ng/mL to 250 ng/mL of CEA. As expected, the Raman signal of the reporter increased with increasing CEA concentrations, and contributed to confirm the accuracy of the analytical data. Overall, this approach is simple, and may be adaptable to new multiplexing devices, also being adaptable to mass production.
- The influence of miRNAs on radiotherapy treatment in prostate cancer – a systematic reviewPublication . Soares, Sílvia; Guerreiro, Susana S.; Cruz-Martins, Natália; Sousa Pinho Faria, Isabel Maria; Baylina, Pilar; Sales, Maria Goretti; Correa-Duarte, Miguel A.; Fernandes, RúbenIn the last years, extensive investigation on miRNomics have shown to have great advantages in cancer personalized medicine regarding diagnosis, treatment and even clinical outcomes. Prostate cancer (PCa) is the second most common male cancer and about 50% of all PCa patients received radiotherapy (RT), despite some of them develop radioresistance. Here, we aim to provide an overview on the mechanisms of miRNA biogenesis and to discuss the functional impact of miRNAs on PCa under radiation response. As main findings, 23 miRNAs were already identified as being involved in genetic regulation of PCa cell response to RT. The mechanisms of radioresistance are still poorly understood, despite it has been suggested that miRNAs play an important role in cell signaling pathways. Identification of miRNAs panel can be thus considered an upcoming and potentially useful strategy in PCa diagnosis, given that radioresistance biomarkers, in both prognosis and therapy still remains a challenge.