Publications

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2024
Detecting mir-155-3p through a Molecular Beacon Bead-Based Assay, Moreira, David, Alexandre Daniela, Miranda André, c}o Pedro Louren{\c, Baptista {Pedro V. }, Tomaz Cândida, Lu Yi, and Cruz Carla , Molecules, Volume 29, Number 13, (2024) Abstract

Lung cancer (LC) is recognized as one of the most prevalent and lethal cancers worldwide, underscoring an urgent need for innovative diagnostic and therapeutic approaches. MicroRNAs (miRNAs) have emerged as promising biomarkers for several diseases and their progression, such as LC. However, traditional methods for detecting and quantifying miRNAs, such as PCR, are time-consuming and expensive. Herein, we used a molecular beacon (MB) bead-based assay immobilized in a microfluidic device to detect miR-155-3p, which is frequently overexpressed in LC. The assay relies on the fluorescence enhancement of the MB upon binding to the target miRNA via Watson and Crick complementarity, resulting in a conformational change from a stem–loop to a linear structure, thereby bringing apart the fluorophores at each end. This assay was performed on a microfluidic platform enabling rapid and straightforward target detection. We successfully detected miR-155-3p in a saline solution, obtaining a limit of detection (LOD) of 42 nM. Furthermore, we evaluated the method’s performance in more complex biological samples, including A549 cells’ total RNA and peripheral blood mononuclear cells (PBMCs) spiked with the target miRNA. We achieved satisfactory recovery rates, especially in A549 cells’ total RNA.

Discovery of Novel Fluorescent Azaindoles with Cytotoxic Action in A2780 Ovarian Carcinoma Cells, Cunha, {José C. }, Roma-Rodrigues Catarina, Ferreira {Joana R. M. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Guieu S., and Marques Manuel {M. B. } , Chemmedchem, Volume 19, Number 20, (2024) Abstract

Azaindole scaffold is a privileged structure in medicinal chemistry and some derivatives have demonstrated to be potential anticancer drugs. Herein, a set of novel azaindoles, comprising the four regioisomers, bearing a morpholine (azaindoles 3a-d) and N-methyl-N-benzylamine (azaindoles 4a-d) groups were prepared. Among these compounds, azaindoles 4 exhibited higher cytotoxicity against the ovarian cancer cell line A2780 and normal dermal fibroblasts compared to azaindoles 3. Furthermore, azaindoles 4b and 4c promoted a delay in the cell cycle of the cancer cell line, inspiring an investigation into the intracellular localization of these derivatives.

2023
Doxorubicin-sensitive and -resistant colorectal cancer spheroid models: assessing tumor microenvironment features for therapeutic modulation, Valente, Ruben, Cordeiro Sandra, Luz André, Rodrigues {Catarina Roma}, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Frontiers in Cell and Developmental Biology, Volume 11, (2023) Abstract

Introduction: The research on tumor microenvironment (TME) has recently been gaining attention due to its important role in tumor growth, progression, and response to therapy. Because of this, the development of three-dimensional cancer models that mimic the interactions in the TME and the tumor structure and complexity is of great relevance to cancer research and drug development. Methods: This study aimed to characterize colorectal cancer spheroids overtime and assess how the susceptibility or resistance to doxorubicin (Dox) or the inclusion of fibroblasts in heterotypic spheroids influence and modulate their secretory activity, namely the release of extracellular vesicles (EVs), and the response to Dox-mediated chemotherapy. Different characteristics were assessed over time, namely spheroid growth, viability, presence of hypoxia, expression of hypoxia and inflammation-associated genes and proteins. Due to the importance of EVs in biomarker discovery with impact on early diagnostics, prognostics and response to treatment, proteomic profiling of the EVs released by the different 3D spheroid models was also assessed. Response to treatment was also monitored by assessing Dox internalization and its effects on the different 3D spheroid structures and on the cell viability. Results and Discussion: The results show that distinct features are affected by both Dox resistance and the presence of fibroblasts. Fibroblasts can stabilize spheroid models, through the modulation of their growth, viability, hypoxia and inflammation levels, as well as the expressions of its associated transcripts/proteins, and promotes alterations in the protein profile exhibit by EVs. Summarily, fibroblasts can increase cell-cell and cell-extracellular matrix interactions, making the heterotypic spheroids a great model to study TME and understand TME role in chemotherapies resistance. Dox resistance induction is shown to influence the internalization of Dox, especially in homotypic spheroids, and it is also shown to influence cell viability and consequently the chemoresistance of those spheroids when exposed to Dox. Taken together these results highlight the importance of finding and characterizing different 3D models resembling more closely the in vivo interactions of tumors with their microenvironment as well as modulating drug resistance.

2022
Digital Microfluidics-Powered Real-Time Monitoring of Isothermal DNA Amplification of Cancer Biomarker, Coelho, {Beatriz Jorge}, Veigas Bruno, Bettencourt Luís, Águas Hugo, Fortunato Elvira, Martins Rodrigo, Baptista {Pedro V. }, and Igreja Rui , Biosensors, mar, Volume 12, Number 4, (2022) Abstract

We introduce a digital microfluidics (DMF) platform specifically designed to perform a loop-mediated isothermal amplification (LAMP) of DNA and applied it to a real-time amplification to monitor a cancer biomarker, c-Myc (associated to 40% of all human tumors), using fluorescence microscopy. We demonstrate the full manipulation of the sample and reagents on the DMF platform, resulting in the successful amplification of 90 pg of the target DNA (0.5 ng/µL) in less than one hour. Furthermore, we test the efficiency of an innovative mixing strategy in DMF by employing two mixing methodologies onto the DMF droplets—low frequency AC (alternating current) actuation as well as back-and-forth droplet motion—which allows for improved fluorescence readouts. Fluo-rophore bleaching effects are minimized through on-chip sample partitioning by DMF processes and sequential droplet irradiation. Finally, LAMP reactions require only 2 µL volume droplets, which represents a 10-fold volume reduction in comparison to benchtop LAMP.

2021
Drug delivery nanosystems targeted to hepatic ischemia and reperfusion injury, Ferreira-Silva, Margarida, Faria-Silva Catarina, Baptista {Pedro Viana}, Fernandes Eduarda, Fernandes {Alexandra Ramos}, and Corvo {Maria Luísa} , Drug delivery and translational research, apr, Volume 11, Number 2, p.397–410, (2021) Abstract

Abstract: Hepatic ischemia and reperfusion injury (IRI) is an acute inflammatory process that results from surgical interventions, such as liver resection surgery or transplantation, or hemorrhagic shock. This pathology has become a severe clinical issue, due to the increasing incidence of hepatic cancer and the high number of liver transplants. So far, an effective treatment has not been implemented in the clinic. Despite its importance, hepatic IRI has not attracted much interest as an inflammatory disease, and only a few reviews addressed it from a therapeutic perspective with drug delivery nanosystems. In the last decades, drug delivery nanosystems have proved to be a major asset in therapy because of their ability to optimize drug delivery, either by passive or active targeting. Passive targeting is achieved through the enhanced permeability and retention (EPR) effect, a main feature in inflammation that allows the accumulation of the nanocarriers in inflammation sites, enabling a higher efficacy of treatment than conventional therapies. These systems also can be actively targeted to specific compounds, such as inflammatory markers and overexpressed receptors in immune system intermediaries, allowing an even more specialized therapy that have already showed encouraging results. In this manuscript, we review drug delivery nanosystems designed for hepatic IRI treatment, addressing their current state in clinical trials, discussing the main hurdles that hinder their successful translation to the market and providing some suggestions that could potentially advance their clinical translation. Graphical abstract: [Figure not available: see fulltext.].

2018
A double Philadelphia chromosome-positive chronic myeloid leukemia patient, co-expressing P210BCR-ABL1 and P195BCR-ABL1 isoforms, Vinhas, Raquel, Louren{\c c}o Alexandra, Santos Susana, Ribeiro Patrícia, Silva Madalena, {de Sousa} {Aida Botelho}, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Haematologica, nov, Volume 103, Number 11, p.e549–e552, (2018) Abstract
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2017
A digital microfluidics platform for loop-mediated isothermal amplification detection, Coelho, {Beatriz Jorge}, Veigas Bruno, Águas Hugo, Fortunato Elvira, Martins Rodrigo, Baptista {Pedro Viana}, and Igreja Rui , Sensors, nov, Volume 17, Number 11, (2017) Abstract

Digital microfluidics (DMF) arises as the next step in the fast-evolving field of operation platforms for molecular diagnostics. Moreover, isothermal schemes, such as loop-mediated isothermal amplification (LAMP), allow for further simplification of amplification protocols. Integrating DMF with LAMP will be at the core of a new generation of detection devices for effective molecular diagnostics at point-of-care (POC), providing simple, fast, and automated nucleic acid amplification with exceptional integration capabilities. Here, we demonstrate for the first time the role of coupling DMF and LAMP, in a dedicated device that allows straightforward mixing of LAMP reagents and target DNA, as well as optimum temperature control (reaction droplets undergo a temperature variation of just 0.3°C, for 65°C at the bottom plate). This device is produced using low-temperature and low-cost production processes, adaptable to disposable and flexible substrates. DMF-LAMP is performed with enhanced sensitivity without compromising reaction efficacy or losing reliability and efficiency, by LAMP-amplifying 0.5 ng/µL of target DNA in just 45 min. Moreover, on-chip LAMP was performed in 1.5 µL, a considerably lower volume than standard bench-top reactions.

Digital microfluidics for nucleic acid amplification, Coelho, Beatriz, Veigas Bruno, Fortunato Elvira, Martins Rodrigo, Águas Hugo, Igreja Rui, and Baptista {Pedro V. } , Sensors, jul, Volume 17, Number 7, (2017) Abstract

Digital Microfluidics (DMF) has emerged as a disruptive methodology for the control and manipulation of low volume droplets. In DMF, each droplet acts as a single reactor, which allows for extensive multiparallelization of biological and chemical reactions at a much smaller scale. DMF devices open entirely new and promising pathways for multiplex analysis and reaction occurring in a miniaturized format, thus allowing for healthcare decentralization from major laboratories to point-of-care with accurate, robust and inexpensive molecular diagnostics. Here, we shall focus on DMF platforms specifically designed for nucleic acid amplification, which is key for molecular diagnostics of several diseases and conditions, from pathogen identification to cancer mutations detection. Particular attention will be given to the device architecture, materials and nucleic acid amplification applications in validated settings.

2015
DNA adduct identification using gold-aptamer nanoprobes, Larguinho, Miguel, Santos Sofia, Almeida Joao, and Baptista Pedro , Iet Nanobiotechnology, apr, Volume 9, Number 2, p.95–101, (2015) Abstract

The optical and physico-chemical properties of gold nanoparticles (AuNPs) have prompted new and improved approaches which have greatly evolved the fields of biosensing and molecular detection. In this study, the authors took advantage of AuNPs' ease of modification and functionalised it with selected DNA aptamers using a salt aging method to produce gold-aptamer nanoprobes. After characterisation, these nanoprobes were subsequently used for biomolecular detection of glycidamide (GA)-guanine (Gua) adducts generated in vitro. The results are based on differences in nanoprobe stabilisation against salt-induced aggregation, similar to the non-cross-linking method developed by Baptista for discrimination of specific sequences. Alkylated Guas were efficiently discriminated from deoxyguanosine and GA in solution. Despite this, a clear identification of DNA adducts derived from genomic DNA alkylation has proven to be a more challenging task.

2014
Dual-color control of nucleotide polymerization sensed by a fluorescence actuator, Reimão-Pinto, {Madalena M. }, Cordeiro Ana, Almeida Carina, Pinheiro {Andre V. }, Moro Artur, Lima {João C. }, and Baptista Pedro , Photochemical & Photobiological Sciences, Volume 13, Number 5, p.751–756, (2014) Abstract

Spatial and temporal control of molecular mechanisms can be achieved using photolabile bonds that connect biomolecules to protective caging groups, which can be cleaved upon irradiation of a specific wavelength, releasing the biomolecule ready-to-use. Here we apply and improve a previously reported strategy to tightly control in vitro transcription reactions. The strategy involves two caging molecules that block both ATP and GTP nucleotides. Additionally, we designed a molecular beacon complementary to the synthesized mRNA to infer its presence through a light signal. Upon release of both nucleotides through a specific monochromatic light (390 and 325 nm) we attain a light signal indicative of a successful in vitro transcription reaction. Similarly, in the absence of irradiation, no intense fluorescence signal was obtained. We believe this strategy could further be applied to DNA synthesis or the development of logic gates.

2013
Designing gold nanoparticles for in vivo gene silencing as a new therapeutic tool, Conde, João, Ambrosone A., Hernandez Yulan, Marchesano V., Tian Furong, {Ricardo Ibarra} M., Baptista {Pedro Viana}, Tortiglione C., and {de la Fuente} {Jesus M. } , Human Gene Therapy, dec, Volume 24, Number 12, p.A24–A24, (2013) Abstract
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Detec{\c c}ão de MDRTB por gold-nanoprobes – uma nova abordagem tecnológica desenvolvida em Portugal, Pedrosa, Pedro, Veigas Bruno, Machado Diana, Perdigão João, Portugal Isabel, Couto Isabel, Viveiros Miguel, and Baptista {Pedro V. } , (2013) Abstract
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2012
Design of multifunctional gold nanoparticles for in vitro and in vivo gene silencing, Conde, João, Ambrosone Alfredo, Sanz Vanesa, Hernandez Yulan, Marchesano Valentina, Tian Furong, Child Hannah, Berry {Catherine C. }, Ibarra Ricardo} {M., Baptista {Pedro V. }, Tortiglione Claudia, and {de la Fuente} {Jesus M. } , ACS Nano, sep, Volume 6, Number 9, p.8316–8324, (2012) Abstract

Over the past decade, the capability of double-stranded RNAs to interfere with gene expression has driven new therapeutic approaches. Since small interfering RNA (siRNAs, 21 base pair double-stranded RNA) was shown to be able to elicit RNA interference (RNAi), efforts were directed toward the development of efficient delivery systems to preserve siRNA bioactivity throughout the delivery route, from the administration site to the target cell. Here we provide evidence of RNAi triggering, specifically silencing c-myc protooncogene, via the synthesis of a library of novel multifunctional gold nanoparticles (AuNPs). The efficiency of the AuNPs is demonstrated using a hierarchical approach including three biological systems of increasing complexity: in vitro cultured human cells, in vivo invertebrate (freshwater polyp, Hydra), and in vivo vertebrate (mouse) models. Our synthetic methodology involved fine-tuning of multiple structural and functional moieties. Selection of the most active functionalities was assisted step-by-step through functional testing that adopted this hierarchical strategy. Merging these chemical and biological approaches led to a safe, nonpathogenic, self-tracking, and universally valid nanocarrier that could be exploited for therapeutic RNAi.

2010
Development of a fast and efficient ultrasonic-based strategy for DNA fragmentation, Larguinho, Miguel, Santos {Hugo M. }, c}alo Doria Gon{\c, Scholz H., Baptista {Pedro V. }, and Capelo {José L. } , Talanta, may, Volume 81, Number 3, p.881–886, (2010) Abstract

Several ultrasound-based platforms for DNA sample preparation were evaluated in terms of effective fragmentation of DNA (plasmid and genomic DNA)-ultrasonic probe, sonoreactor, ultrasonic bath and the newest Vialtweeter device. The sonoreactor showed the best efficiency of DNA fragmentation while simultaneously assuring no cross-contamination of samples, and was considered the best ultrasonic tool to achieve effective fragmentation of DNA at high-throughput and avoid sample overheating. Several operation variables were studied-ultrasonication time and amplitude, DNA concentration, sample volume and sample pre-treatment-that allowed optimisation of a sonoreactor-based strategy for effective DNA fragmentation. Optimal operating conditions to achieve DNA fragmentation were set to 100% ultrasonic amplitude, 100 μL sample volume, 8 min ultrasonic treatment (2 min/sample) for a DNA concentration of 100 μg mL-1. The proposed ultrasonication strategy can be easily implemented in any laboratory setup, providing fast, simple and reliable means for effective DNA sample preparation when fragmentation is critical for downstream molecular detection and diagnostics protocols.

Detection and quantification system of biological, matter constituted by one or more optical sensors and one or more light sources, associated process and related applications, Martins, {Rodrigo Ferrão De Paiva}, Baptista {Pedro Miguel Ribeiro Viana}, and Fortunato {Elvira Maria Correia} , feb, (2010) Abstract

The present invention relates to a system and process for detection and/or qualitative and quantitative identification of the biological material, such as specific sequences of nucleic acids or proteins as antibodies, present in biological samples. The system is composed by one or more light sources (1) combined with one or more integrated optical photo sensors, or not, and various electronic components (4), necessary for obtaining/processing of the signal emitted by the metal nanoprobes functionalized with a solution of biological composite, as well as also a micro-controller and a microprocessor, fixed or portable. This photosensor structure is able to detect and to quantify the colour variations produced by metal nanoprobes, being this preferentially gold, functionalized by oligonucleotides complementary to specific DNA/RNA sequences, proteins, as for instance antibodies and/or antigens related with certain disease, or other sample or solution of biological composite, that are to be investigated. The detection and quantification process is based on the response of a photosensor, singular or integrated, based on thin film technology of amorphous, nanocrystalline or microcrystalline silicon and their alloys, as well as the new active ceramic semiconductors, amorphous and not amorphous.

2009
Detection and quantification system of biological matter constituted by one or more optical sensors and one or more light sources, associated process and related applications, Martins, {Rodrigo Ferrao De Paiva}, Baptista {Pedro Miguel Ribeiro Viana}, and Fortunato {Elvira Maria Correia} , may, (2009) Abstract

The present invention relates to a system and process for detection and/or qualitative and quantitative identification of the biological material, such as specific sequences of nucleic acids or proteins as antibodies, present in biological samples. The system is composed by one or more light sources (1) combined with one or more integrated optical photo sensors, or not, and various electronic components (4), necessary for obtaining/ processing of the signal emitted by the metal nanoprobes functionalized with a solution of biological composite, as well as also a micro-controller and a microprocessor, fixed or portable. This photosensor structure is able to detect and to quantify the colour variations produced by metal nanoprobes, being this preferentially gold, functionalized by oligonucleotides complementary to specific DNA/RNA sequences, proteins, as for instance antibodies and/or antigens related with certain disease, or other sample or solution of biological composite, that are to be investigated. The detection and quantification process is based on the response of a photosensor, singular or integrated, based on thin film technology of amorphous, nanocrystalline or microcrystalline silicon and their alloys, as well as the new active ceramic semiconductors, amorphous and not amorphous.

Detection and quantification system of biological matter constituted by one or more optical sensors and one or more light sources, associated process and related applications, Martins, {Rodrigo Ferrao De Paiva}, Baptista {Pedro Miguel Ribeiro Viana}, and Fortunato {Elvira Maria Correia} , dec, (2009) Abstract
n/a
2008
Detection and quantification system of biological matter constituted by one or more optical sensors and one or more light sources, associated process and related applications, Martins, {Rodrigo Ferrao De Paiva}, Baptista {Pedro Miguel Ribeiro Viana}, and Fortunato {Elvira Maria Correia} , mar, (2008) Abstract

The present invention relates to a system and process for detection and/or qualitative and quantitative identification of the biological material, such as specific sequences of nucleic acids or proteins as antibodies, present in biological samples. The system is composed by one or more light sources (1) combined with one or more integrated optical photo sensors, or not, and various electronic components (4), necessary for obtaining/ processing of the signal emitted by the metal nanoprobes functionalized with a solution of biological composite, as well as also a micro-controller and a microprocessor, fixed or portable. This photosensor structure is able to detect and to quantify the colour variations produced by metal nanoprobes, being this preferentially gold, functionalized by oligonucleotides complementary to specific DNA/RNA sequences, proteins, as for instance antibodies and/or antigens related with certain disease, or other sample or solution of biological composite, that are to be investigated. The detection and quantification process is based on the response of a photosensor, singular or integrated, based on thin film technology of amorphous, nanocrystalline or microcrystalline silicon and their alloys, as well as the new active ceramic semiconductors, amorphous and not amorphous.