Cookies Policy
We use cookies to improve our site and your experience. By continuing to browse our site you accept our cookie policy. Find out More
Close
  • Menu
About

About

I am a professor in the Physics Department of University de Trás-os-Montes e Alto Douro and senior researcher at Center of Applied Photonics of INESC-TEC. I have received my Ph.D. in Physics from Porto University in 2005. I am specialized in the deposition of thin films of functional materials using laser ablation and sputtering techniques for sensor and actuator applications. Presently my research interests include the development of optical biosensors for DNA identification, the development of UV LED's optical sources for wastewater treatment, and the study of the physical properties of thin films of functional materials.

Interest
Topics
Details

Details

003
Publications

2018

Applying high-resolution melting (HRM) technology to olive oil and wine authenticity

Authors
Pereira, L; Gomes, S; Barrias, S; Fernandes, JR; Martins Lopes, P;

Publication
Food Research International

Abstract
Olive oil and wine production have a worldwide economic impact. Their market reliability is under great concern because of the increasing number of fraud and adulteration attempts. The need for a traceability system in all its extension is crucial particularly for the cases of olive oils and wines with certified labels, in which only a limited number of olives and grapevine varieties, respectively, are allowed in a restricted well-defined geographical area. Molecular markers have been vastly applied to the food sector, and in particular High-Resolution DNA Melting technology has been successfully applied for olive oil and wine authentication, as part of the traceability system. In this review, the applications of HRM and their usefulness for this sector considering, Safety, Security and Authenticity will be reviewed. A broad overview of the HRM technique will be presented, focusing on the aspects that are crucial for its success, in particular the new generation of fluorescent dsDNA dyes used for amplicon detection and quantification, and the data analysis. A brief outlook on the olive oil and wine authenticity procedures, based on new DNA technology advances, and in which way this may influence the future establishment of a traceability system will be discussed. © 2017 Elsevier Ltd

2018

Alternative SNP detection platforms, HRM and biosensors, for varietal identification in Vitis vinifera L. using F3H and LDOX genes

Authors
Gomes, S; Castro, C; Barrias, S; Pereira, L; Jorge, P; Fernandes, JR; Martins Lopes, P;

Publication
SCIENTIFIC REPORTS

Abstract
The wine sector requires quick and reliable methods for Vitis vinifera L. varietal identification. The number of V. vinifera varieties is estimated in about 5,000 worldwide. Single Nucleotide Polymorphisms (SNPs) represent the most basic and abundant form of genetic sequence variation, being adequate for varietal discrimination. The aim of this work was to develop DNA-based assays suitable to detect SNP variation in V. vinifera, allowing varietal discrimination. Genotyping by sequencing allowed the detection of eleven SNPs on two genes of the anthocyanin pathway, the flavanone 3-hydroxylase (F3H, EC: 1.14.11.9), and the leucoanthocyanidin dioxygenase (LDOX, EC 1.14.11.19; synonym anthocyanidin synthase, ANS) in twenty V. vinifera varieties. Three High Resolution Melting (HRM) assays were designed based on the sequencing information, discriminating five of the 20 varieties: Alicante Bouschet, Donzelinho Tinto, Merlot, Moscatel Galego and Tinta Roriz. Sanger sequencing of the HRM assay products confirmed the HRM profiles. Three probes, with different lengths and sequences, were used as bio-recognition elements in an optical biosensor platform based on a long period grating (LPG) fiber optic sensor. The label free platform detected a difference of a single SNP using genomic DNA samples. The two different platforms were successfully applied for grapevine varietal identification.

2017

The role of PbTiO3 layers in piezoelectric multilayer composite films based on Pb(Mg1/3Nb2/3)O-3-PbTiO3

Authors
El Hosiny Ali, HE; Jimenez, R; Ramos, P; de la Cruz, JP; Fernandes, JRA; Bretos, I; Calzada, ML; Ricote, J;

Publication
THIN SOLID FILMS

Abstract
The sharp decrease of the remnant ferroelectric and piezoelectric properties of Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMNT) thin films close to the Morphotropic Phase Boundary (MPB) respect to their corresponding bulk ceramics is a major drawback for their integration in microdevices. In order to take full advantage of the excellent piezoelectric properties of polycrystalline PMNT in thin film form, a multilayer configuration with PbTiO3 (PT) layers is proposed. The PT layers generate an internal electric bias within the PMNT layer, which anchor an induced polarization in it. This results in a significant improvement of the piezoelectric behavior, obtaining remnant piezoelectric coefficients, d(33) (r), as high as 67 pm V-1. The role of the thickness of the PT layers used is discussed, in order to find the optimum configuration for these multilayers.

2017

Synthesis, spectroscopic characterization and biological evaluation of unsymmetrical aminosquarylium cyanine dyes

Authors
Friaes, S; Silva, AM; Boto, RE; Ferreira, D; Fernandes, JR; Souto, EB; Almeida, P; Vieira Ferreira, LFV; Reis, LV;

Publication
BIOORGANIC & MEDICINAL CHEMISTRY

Abstract
New unsymmetrical aminosquarylium cyanine dyes were synthesized and their potential as photosensitizers evaluated. New dyes, derived from benzothiazole and quinoline, were prepared by nucleophilic substitution of the corresponding O-methylated, the key intermediate that was obtained by methylation with CF3SO3CH3 of the related zwitterionic unsymmetrical dye, with ammonia and methylamine, respectively. All three news dyes herein described displayed intense and narrow bands in the Vis/NIR region (693-714 nm) and their singlet oxygen formation quantum yields ranged from 0.03 to 0.05. In vitro toxicity, in Caco-2 and HepG2 cells, indicated that dark toxicity was absent for concentrations up to 5 mu M (for the less active dye) or up to 1 mu M (for the two more active dyes). The three dyes present potential as photosensitizers, differing in irradiation conditions and period of incubation in the presence of irradiated dye. The less active dye needs a longer irradiation period to exhibit phototoxicity which is only evident after longer period of contact with cells (24 h). However, the remaining two more active dyes produce higher phototoxicity, even at shorter incubation periods (1 h), with shorter irradiation time (7 min). Although in different extents, these dyes show promising in vitro results as photosensitizers.

2017

Disinfection of simulated and real winery wastewater using sulphate radicals: Peroxymonosulphate/transition metal/UV-A LED oxidation

Authors
Rodriguez Chueca, J; Moreira, SI; Lucas, MS; Fernandes, JR; Tavares, PB; Sampaio, A; Peres, JA;

Publication
JOURNAL OF CLEANER PRODUCTION

Abstract
The inactivation of four different microorganisms, Escherichia coli, Bacillus mycoides, Staphylococcus aureus and Candida albicans, inoculated in simulated (SWW) and real winery wastewaters (RWW), was assessed by the first time using free sulphate and hydroxyl radicals from photolytic (UV-A LED radiation; 370 nm) and metal [Fe(II) or Co(II)] activation of peroxymonosulphate (PMS). The experimental conditions tested were [PMS] = 0.1 mM and [Fe(II) or Co(II)] = 0.1 mM and pH 5.0 for the inactivation of microorganisms in SWW. However, due to the complexity of the water matrix, not unexpectedly, a fivefold concentration of reagents was required to inactivate the same organisms in RWW. In addition, compared to the bacteria, the fungus C. albicans presented a higher oxidative stress resistance to the treatments, and different experimental conditions were necessary to inactivate these cells. After 90 min, the photolytic activation of PMS through UV-A LED radiation achieved complete inactivation of E. coli, followed by S. aureus (approximate to 4 log) and B. mycoides (approximate to 3 log). Total inactivation of C. albicans was also achieved, but with higher dosages of PMS (10 mM). The metal activation of PMS through the use of a transition metal [Fe(II) or Co(II)] accelerated the inactivation rate, particularly in the first minutes of exposure time. These treatments reached between 1 and 3 log inactivation of microorganisms in the first minute of the experiment. In addition, the use of Co(II) as promoter in the activation of PMS, was more effective in the inactivation of S. aureus and C. albicans than activation with Fe(II). Since linear mathematical models do not adjust satisfactorily to inactivation results in all cases, different mathematical models were tested to fit the experimental inactivation data. In general, the Hom model correctly fits the inactivation results of the four microorganisms in all applied treatments. However, other models such as Biphasic and Double Weibull fit acceptably as well.

Supervised
thesis

2016

Estudo do efeito da temperatura sobre as propriedades mecânicas da madeira através de espectroscopia mecânica e acústica

Author
Lionel Vieira de Barros

Institution
UTAD

2016

-

Author
Chong liu

Institution
UM

2016

Deposição de filmes do sistema (Bi,Lu)-Fe-O e estudo da sua potencial utilização como biossensores

Author
Ana Flávia Cardoso

Institution
UTAD

2016

Effect of the probe structure design in the biossensor response: the case of Vitis Vinifera L.

Author
Sara Isabel Mourão Barrias

Institution
UTAD