João Tomé

Prof. Dr. João Tomé

Department of Chemical Engineering & CQE, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, nº 1, 1049-001 Lisboa, Portugal

Research Focus & Metrics

Academic Career Length

30Years (1997-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 July 2015 in Chemical Society Reviews
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Journal Article
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PSPatrícia Silva
Patrícia Silva
SVSérgio Vilela
Sérgio Vilela
João ToméJoão Tomé
João Tomé
Filipe Almeida PazFilipe Almeida Paz
Filipe Almeida Paz
After three decades of intense and fundamental research on metal–organic frameworks (MOFs), is there anything left to say or to explain? The synthesis and properties of MOFs have already been comprehensively described elsewhere. It is time, however, to prove the nature of their true usability: technological applications based on these extended materials require development and implementation as a natural consequence of the up-to-known intensive research focused on their design and preparation. The current large number of reviews on MOFs emphasizes practical strategies to develop novel networks with varied crystal size, shape and topology, being mainly devoted to academic concerns. The present survey intends to push the boundaries and summarise the state-of-the-art on the preparation of promising (multi)functional MOFs in worldwide laboratories and their use as materials for industrial implementation. This review starts, on the one hand, to describe several tools and striking examples of remarkable and recent (multi)functional MOFs exhibiting outstanding properties (e.g., in gas adsorption and separation, selective sorption of harmful compounds, heterogeneous catalysis, luminescent and corrosion protectants). On the other hand, and in a second part, it intends to use these examples of MOFs to incite scientists to move towards the transference of knowledge from the laboratories to the industry. Within this context, we exhaustively review the many efforts of several worldwide commercial companies to bring functional MOFs towards the daily use, analysing the various patents and applications reported to date. Overall, this review goes from the very basic concepts of functional MOF engineering and preparation ending up in their industrial production on a large scale and direct applications in society.

15 September 2011 in Chemical Society Reviews
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Filipe Almeida PazFilipe Almeida Paz
Filipe Almeida Paz
JKJacek Klinowski
Jacek Klinowski
SVSérgio Vilela
Sérgio Vilela
João ToméJoão Tomé
João Tomé
JCJosé Cavaleiro
José Cavaleiro
João RochaJoão Rocha
João Rocha
Metal–organic frameworks (MOFs), also known as coordination polymers, are formed by the self-assembly of metallic centres and bridging organic linkers. In this critical review, we review the key advances in the field and discuss the relationship between the nature and structure of specifically designed organic linkers and the properties of the products. Practical examples demonstrate that the physical and chemical properties of the linkers play a decisive role in the properties of novel functional MOFs. We focus on target materials suitable for the storage of hydrogen and methane, sequestration of carbon dioxide, gas separation, heterogeneous catalysis and as magnetic and photoluminescent materials capable of both metal- and ligand-centred emission, ion exchangers and molecular sieves. The advantages of highly active discrete complexes as metal-bearing ligands in the construction of MOFs are also briefly reviewed (128 references).

20 January 2010 in Marine Drugs
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ATAnabela Tavares
Anabela Tavares
CCCarla M. B. Carvalho
Carla M. B. Carvalho
Maria Amparo FaustinoMaria Amparo Faustino
Maria Amparo Faustino
Maria NevesMaria Neves
Maria Neves
João ToméJoão Tomé
João Tomé
Adelaide AlmeidaAdelaide Almeida
Adelaide Almeida
Antimicrobial photodynamic therapy (aPDT) has emerged in the clinical field as a potential alternative to antibiotics to treat microbial infections. No cases of microbial viability recovery or any resistance mechanisms against it are yet known. 5,10,15-tris(1-Methylpyridinium-4-yl)-20-(pentafluorophenyl)-porphyrin triiodide (Tri-Py+-Me-PF) was used as photosensitizer. Vibrio fischeri and recombinant Escherichia coli were the studied bacteria. To determine the bacterial recovery after treatment, Tri-Py+-Me-PF (5.0 µM) was added to bacterial suspensions and the samples were irradiated with white light (40 W m-2) for 270 minutes. Then, the samples were protected from light, aliquots collected at different intervals and the bioluminescence measured. To assess the development of resistance after treatment, bacterial suspensions were exposed to white light (25 minutes), in presence of 5.0 μM of Tri-Py+-Me-PF (99.99% of inactivation) and plated. After the first irradiation period, surviving colonies were collected from the plate and resuspended in PBS. Then, an identical protocol was used and repeated ten times for each bacterium. The results suggest that aPDT using Tri-Py+-Me-PF represents a promising approach to efficiently destroy bacteria since after a single treatment these microorganisms do not recover their viability and after ten generations of partially photosensitized cells neither of the bacteria develop resistance to the photodynamic process.

28 January 2014 in Future Medicinal Chemistry
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Journal Article
Closed access
EAEliana Alves
Eliana Alves
Maria Amparo FaustinoMaria Amparo Faustino
Maria Amparo Faustino
Maria NevesMaria Neves
Maria Neves
Angela CunhaAngela Cunha
Angela Cunha
João ToméJoão Tomé
João Tomé
Adelaide AlmeidaAdelaide Almeida
Adelaide Almeida
The emergence of microbial resistance is becoming a global problem in clinical and environmental areas. As such, the development of drugs with novel modes of action will be vital to meet the threat...

15 April 2009 in BMC Microbiology
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EAEliana Alves
Eliana Alves
LCLiliana Costa
Liliana Costa
CCCarla Mb Carvalho
Carla Mb Carvalho
João ToméJoão Tomé
João Tomé
Maria Amparo FaustinoMaria Amparo Faustino
Maria Amparo Faustino
Adelaide AlmeidaAdelaide Almeida
Adelaide Almeida
Background: In recent times photodynamic antimicrobial therapy has been used to efficiently destroy Gram (+) and Gram (-) bacteria using cationic porphyrins as photosensitizers. There is an increasing interest in this approach, namely in the search of photosensitizers with adequate structural features for an efficient photoinactivation process. In this study we propose to compare the efficiency of seven cationic porphyrins differing in meso-substituent groups, charge number and charge distribution, on the photodynamic inactivation of a Gram (+) bacterium (Enterococcus faecalis) and of a Gram (-) bacterium (Escherichia coli). The present study complements our previous work on the search for photosensitizers that might be considered good candidates for the photoinactivation of a large spectrum of environmental microorganisms. Results: Bacterial suspension (107 CFU mL-1) treated with different photosensitizers concentrations (0.5, 1.0 and 5.0 μM) were exposed to white light (40 W m-2) for a total light dose of 64.8 J cm-2. The most effective photosensitizers against both bacterial strains were the Tri-Py+-Me-PF and Tri-Py+-Me-CO2Me at 5.0 μM with a light fluence of 64.8 J cm-2, leading to > 7.0 log (> 99,999%) of photoinactivation. The tetracationic porphyrin also proved to be a good photosensitizer against both bacterial strains. Both di-cationic and the monocationic porphyrins were the least effective ones. Conclusion: The number of positive charges, the charge distribution in the porphyrins' structure and the meso-substituent groups seem to have different effects on the photoinactivation of both bacteria. As the Tri-Py+-Me-PF porphyrin provides the highest log reduction using lower light doses, this photosensitizer can efficiently photoinactivate a large spectrum of environmental bacteria. The complete inactivation of both bacterial strains with low light fluence (40 W m-2) means that the photodynamic approach can be applied to wastewater treatment under natural light conditions which makes this technology cheap and feasible in terms of the light source.

6 July 2015 in Future Medicinal Chemistry
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Journal Article
Closed access
Adelaide AlmeidaAdelaide Almeida
Adelaide Almeida
Maria Amparo FaustinoMaria Amparo Faustino
Maria Amparo Faustino
João ToméJoão Tomé
João Tomé