Novos sitemas  óticos biomiméticos para o seguimento de biomarcadores de cancro

Funder

Organizational Unit

Publications

Molecularly imprinted polymer for Mucin 4 (MUC4) biomarker

Publication . Piloto, A.M.L.; Cerqueira, N.; Sales, Goreti

(Introduction) Molecularly imprinted polymers (MIPs) were synthesized around quantum dots (QDs) to detect the protein biomarker MUC4, which is associated with pancreatic cancer (Kauretal.,2022; Mehrotraetal.,2024). In this approach, MIPs serve as biorecognition elements and are conjugated with cadmium telluride QDs to form the sensing system. The fluorescence of these imprinted polymers is quenched as MUC4 concentrations increase, demonstrating a linear response within the range of 0.12 ng/mL to 16.9 ng/mL in human serum. This range is below the pancreatic cancer diagnostic cut-off values (1.2 to 1.3 ng/mL). The MIPs exhibit good stability and selectivity for MUC4 compared to non-imprinted controls. Additionally, theoretical studies provide valuable insights for the prediction of the functional structure of MIPs, enhancing its selectivity for the target, while reducing time and costs associated with laborious benchtop assays, which may provide an effective tool for tailoring MIPs to other biomarkers for clinical diagnosis.

2024Conference object

Open access

Paper-based approach for cancer biomarker MMP7 detection using quantum dots and molecularly imprinted polymers

Publication . Oliveira, Pedro; Piloto, Ana Margarida L.

(Introduction) Preliminary investigation using lab-on-paper Molecular Imprinted Polymers (MIPs) paired with Quantum Dots (QDs) to detect Matrix Metalloproteinase-7 (MMP7) using image processing to quantify fluorescence and area with a CMOS sensor reflex camera. MMP7 is critical in pancreatic tumor formation, which has the lowest survival rate among malignant malignancies. High levels of the MMP7 in blood have been associated to a poor prognosis and limited survival in patients. CdTe Quantum Dots (CdTe@MPA QDs) are luminescent nanoparticles with narrow emission spectra, enabling for exceptional sensitive detection of biomarkers.Combination of MIPs with CdTe MPA-capped provide selectivitive for biomiarker.

2024Conference object

Open access

Detection of CA19-9 using fluorescent polymer imprinted membranes

Publication . Xu, Ana; Piloto, Ana Margarida L.

(Introduction) The Carbohydrate antigen19-9 (CA19-9) is a biomarker widely used for the diagnosis and monitoring of various types of cancer, especially pancreatic cancer (PC). Molecularly Imprinted Polymers (MIPs) are synthetic materials with recognition sites molecularly designed to bind selectively to a target analyte, providing high specificity and sensitivity. In this work, the use of solid supports such as membranes, was used to imprint the MIPs, allowing the creation of robust and easy-to-manipulate biomimetic sensors for the precise and efficient detection of biomarkers, specifically CA19-9.

2024Conference object

Open access

Ratiometric determination of CA19-9 using fluorescent carbon dots and yellow-emitting quantum dots

Publication . Rodrigues, E.; Piloto, A.M.L.

(Introduction) Quantum dots (QDs) have high fluorescence, chemical stability and sensitivity and optical properties. Traditional QDs probes have a single peak, leading to some problems such as systemic errors due to detection conditions and fluorescence background and systemic instability. Ratiometric methods eliminate random changes in QDs fluorescence intensity and reduces optical fluctuations not caused by the target.

2024Conference object

Open access

Development of an immunosensor based on quantum dots with different emissions for the detection of cancer biomarkers

Publication . Oliveira, Daniela; Piloto, Ana Margarida L.

(Introduction) Cancer is a global health challenge, where early detection is crucial to increasing survival rates [1]. Non-invasive, rapid, and affordable diagnostic methods are urgently needed. Immunosensors emerge as promising alternatives to traditional methods such as ELISA, allowing point-of-care (PoC) analyses [2]. This study introduces a fluorescent probe using cadmium telluride quantum dots (CdTe@MPA QDs) to detect the pancreatic cancer biomarker CA 19-9. With the increasing CA 19-9 concentrations, the fluorescence intensity of green-, orange-, and red-emitting QDs@conjugates was reduced, creating a visible colour gradient under a 365 nm UV lamp. The method, suitable for serum analysis, is highly sensitive and selective, with a detection range of 0.31 to 501.9 U mL-1 and analyzed using ImageJ software. These immunosensors offer significant potential for cancer biomarker detection in clinical diagnostics.

2024Conference object

Open access