22 documents found, page 1 of 3
Low-cost photoacoustic system for biomedical applications
Ferreira, João Filipe SObreiro; Pinto, Vânia Cristina Gonçalves; Matos, Tiago; Catarino, Susana Oliveira; Minas, Graça; Sousa, Paulo Jorge TeixeiraRecently, the field of photoacoustic (PA) imaging has garnered significant attention due to its ability to provide high-resolution images and real-time monitoring of biological tissues. However, PA systems have relied on expensive and complex laser sources and detection mechanisms, limiting their accessibility for widespread use in both clinical and research settings. So, this work aims to address these limitat...
A portable and low-cost optical device for pigment-based taxonomic classificati...
Magalhães, Vitor; Pinto, Vânia Cristina Gonçalves; Sousa, Paulo Jorge Teixeira; Afonso, José A.; Gonçalves, L. M.; Fernández, Emilio; Minas, GraçaAvailable online 21 October 2024; The proliferation of certain phytoplankton species may lead to harmful algal blooms (HABs) that can affect living resources and human health. Therefore, an accurate identification of phytoplankton populations is essential for the sustainable management of some activities relevant for the blue economy, such as aquaculture, being also relevant for environmental monitoring and mar...
A proof-of-concept study aiming for the integration of an optical biosensor in ...
Correia, Margarida O.; Sousa, Paulo Jorge Teixeira; Rodrigues, Raquel Oliveira; Minas, GraçaAlzheimer’s disease (AD), a progressive neurodegenerative disorder, is marked by the abnormal production of amyloid-beta (Aβ) fibrils, a key biomarker for diagnosis and illness monitoring. Advanced microfluidic devices, such as brain-on-a-chip (BoC), are innovative preclinical tools with the potential to revolutionize AD early diagnosis and treatment. However, existing BoCs face limitations, including challenge...
Optical sensor system to monitor the pH of circulating media on biomimetic micr...
Mendes, Fernando; Miranda, Inês Sofia Ferreira; Rodrigues, Raquel Oliveira; Ferreira, Gabriel Malheiro; Schütte, Helmut; Gassmann, StefanComunicação: "YEF-ECE 2025 - 9th International Young Engineers Forum on Electrical and Computer Engineering", Lisboa, Portugal. July 4, 2025.; pH is a physiological parameter of great importance in biomedical research. For example, during cell growth process, pH is usually lowered due to the acidic metabolites released by the cells. This decrease on the pH value can affect biological processes and, consequently...
Critical issues on the surface functionalization of plasmonic Au-Ag/TiO2 thin f...
Costa, Diogo; Pereira-Silva, Patrícia; Sousa, Paulo Jorge Teixeira; Pinto, Vânia Cristina Gonçalves; Borges, Joel; Vaz, Filipe; Minas, GraçaThis work reports on the surface functionalization of a nanomaterial supporting localized surface plasmon resonances (LSPRs) with (synthetic) thiolated oligonucleotide-based biorecognition elements, envisaging the development of selective LSPR-based DNA biosensors. The LSPR thin-film transducers are composed of noble metal nanoparticles (NPs) embedded in a TiO2 dielectric matrix, produced cost-effectively and s...
PDMS porous microneedles used as engineered tool in advanced microfluidic devic...
Maia, Renata Patrícia Faria; Sousa, Paulo Jorge Teixeira; Pinto, Vânia Cristina Gonçalves; Soares, Delfim; Lima, Rui Alberto Madeira MacedoThe advancement of organ-on-a-chip (OoC), as end-use preclinical tool, has been slackened with the techno logical and engineering challenges that in-situ real-time monitoring of physicochemical and biological param eters still represent. In this study, the envisioned solution to surpass this challenge is the integration of a microneedle (MN) patch into a microfluidic device to collect cell culture media directl...
Complementary metal oxide semiconductor-based optical detection system for flui...
Santos, André Alves dos; Ferreira, Gabriel Malheiro; Sousa, Paulo Jorge Teixeira; Sousa, Patrícia C.; Catarino, Susana Oliveira; Minas, GraçaAccurate pH sensing is essential for the effective physiological control of the culture media in organ-on-a-chip (OoC) systems. This work proposes a miniaturized optical detection system, based on optical transmittance, for pH level quantification of the EGM™-2 Endothelial Cell Growth Medium-2 BulletKit™ culture medium. Firstly, using a commercial spectrophotometric setup, a set of wavelengths (500, 560, and 60...
A numerical study of the heat distribution generated by a microheater in an org...
Ferreira, Gabriel Malheiro; Sousa, Paulo Jorge Teixeira; Pinto, Vânia Cristina Gonçalves; Catarino, Susana Oliveira; Sousa, Patrícia C.; Minas, GraçaIn an organ-on-a-chip (OoC), temperature must be kept stable for a well-controlled and human representative microenvironment. This work presents the numerical simulation of a microheater to be integrated in a polydimethylsiloxane chamber that will comprise an OoC. Numerical simulations were performed to evaluate the heat distribution, considering the fluid flow and its direction, the microheater and substrate m...
Development and characterization of porous PDMS microneedles
Maia, Renata Patrícia Faria; Sousa, Paulo Jorge Teixeira; Pinto, Vânia Cristina Gonçalves; Lima, Rui Alberto Madeira Macedo; Minas, Graça"IEEE Portuguese Meeting on Bioengineering, e-ISSN 2771-487X"; This study aimed the development and characterization of polydimethylsiloxane (PDMS) porous microneedles (MNs) cast with silica nanoparticles as porogenic material for biomedical applications. To produce the porous PDMS MNs, different concentrations of silica nanoparticles were cast into PDMS, followed by chemical etching to remove the casted materi...
Portable and low-cost fluorometer for phytoplankton monitoring
Sá, Leonardo Rafael Correia; Pinto, Vânia Cristina Gonçalves; Sousa, Paulo Jorge Teixeira; Magalhães, Vitor H.; Carvalho, Denise Andreia Mota"IEEE Portuguese Meeting on Bioengineering, e-ISSN 2771-487X"; Phytoplankton monitoring using fluorescence spectroscopy techniques has been frequently used over time. This monitoring is based on the detection of the main photosynthetic pigment, chlorophyll-a, as its concentration is widely used as a proxy of phytoplankton biomass in the water column. However, the fluorometers available for their measurement and...