Publications

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2021
New non-toxic n-alkyl cholinium-based ionic liquids as excipients to improve the solubility of poorly water-soluble drugs, Jesus, {Ana R. }, Raposo {Luís R. }, Soromenho {Mário R. C. }, Agostinho {Daniela A. S. }, Esperan{\c c}a {José M. S. S. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Reis {Patrícia M. } , Symmetry, nov, Volume 13, Number 11, (2021) Abstract

In this work, we prepared new biocompatible N-alkyl cholinium-based ionic liquids to be used as cosolvents to improve the solubility of poorly water-soluble drugs, namely, sodium diclo-fenac and paracetamol. In this set of ionic liquids, we intend to understand the effect of increasing the asymmetry of the ionic liquid cation/anion by growing the length of one of the alkyl chains attached to the nitrogen center/sulfonate center on the dissolution capacity of the ionic liquid. The addition of these new ionic liquids to water increased the dissolution capacity of the drugs up to four-times that in water, and improved the pharmacodynamic properties of these drugs, especially the case of sodium diclofenac. The intermolecular interactions between the drugs and ionic liquids were investigated by NMR. Two-dimensional1H/1H nuclear overhauser effect spectroscopy (NO-ESY) revealed an interaction between sodium diclofenac and the alaninate anion from the [C2Ch]2[SucAla]. In the case of paracetamol and [C4Ch][C2SO3], it was possible to observe two inter-molecular interactions between the hydroxyl group of paracetamol and two protons from the cation [C4Ch]+. Interestingly, the ionic liquid bearing a succinyl-DL-alaninate anion, [SucAla]2−, and a N-ethyl cholinium cation, [C2Ch]+, which presented the highest ability to dissolve sodium diclofenac, showed no cytotoxicity up to 500 mM. Therefore, this ionic liquid is a potential candidate for drug delivery applications.

2019
Enhancement of water solubility of poorly water-soluble drugs by new biocompatible N-acetyl amino acid N-alkyl cholinium-based ionic liquids, Jesus, {Ana R. }, Soromenho {Mário R. C. }, Raposo {Luís R. }, Esperan{\c c}a {José M. S. S. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Reis {Patrícia M. } , European Journal of Pharmaceutics and Biopharmaceutics, apr, Volume 137, p.227–232, (2019) Abstract

The major challenge of the pharmaceutical industry is to find potential solvents for poorly water-soluble drug molecules. Ionic liquids (ILs) have attracted this industry as (co-) solvents due to their unique physicochemical and biological properties. Herein, a straightforward approach for the enhancement of water solubility of paracetamol and sodium diclofenac is presented, using new biocompatible N-acetyl amino acid N-alkyl cholinium-based ionic liquids as co-solvents (0.2 - 1 mol%). These new ionic liquids were able to increase water solubility of these drugs up to four times higher than in pure water or in an inorganic salt solution. In the presence of these ILs the drugs lipophilicity (log Kow) was not significantly changed for paracetamol, but for sodium diclofenac it was possible to decrease significantly its lipophilicity. Concerning cytotoxicity in human dermal fibroblasts it was observed that ILs did not show a significant toxicity, and were able to improve cell viability compared with the respective precursors.

2017
Multifunctional gold-nanoparticles: A nanovectorization tool for the targeted delivery of novel chemotherapeutic agents, Fernandes, {Alexandra R. }, Jesus João, Martins Pedro, Figueiredo Sara, Rosa Daniela, Martins {Luísa M. R. D. R. S. }, Corvo {Maria Luísa}, Carvalheiro {Manuela C. }, Costa {Pedro M. }, and Baptista {Pedro V. } , Journal of Controlled Release, jan, Volume 245, p.52–61, (2017) Abstract

Due to their small size and unique properties, multifunctional nanoparticles arise as versatile delivery systems easily grafted with a vast array of functional moieties, such as anticancer cytotoxic chemotherapeutics and targeting agents. Here, we formulated a multifunctional gold-nanoparticle (AuNP) system composed of a monoclonal antibody against epidermal growth factor receptor (EGFR) (anti-EGFR D-11) for active targeting and a Co(II) coordination compound [CoCl(H2O)(phendione)2][BF4] (phendione = 1,10-phenanthroline-5,6-dione) (TS265) with proven antiproliferative activity towards cancer cells (designated as TargetNanoTS265). The efficacy of this nanoformulation, and the non-targeted counterpart (NanoTS265), were evaluated in vitro using cancer cell models and in vivo using mice xenografts. Compared to the free compound, both nanoformulations (TargetNanoTS265 and NanoTS265) efficiently delivered the cytotoxic cargo in a controlled selective manner due to the active targeting, boosting tumor cytotoxicity. Treatment of HCT116-derived xenografts tumors with TargetNanoTS265 led to 93% tumor reduction. This simple conceptual nanoformulation demonstrates the potential of nanovectorization of chemotherapeutics via simple assembly onto AuNPs of BSA/HAS-drug conjugates that may easily be expanded to suit other cargo of novel compounds that require optimized controlled delivery to cancer target.

Targeting canine mammary tumours via gold nanoparticles functionalized with promising Co(II) and Zn(II) compounds, Raposo, {Luis R. }, Roma-Rodrigues Catarina, Jesus Joao, Martins {L. M. D. R. S., Pombeiro {Armando J. L. }, Baptista {P. V. }, and Fernandes {A. R. } , Veterinary and Comparative Oncology, dec, Volume 15, Number 4, p.1537–1542, (2017) Abstract

Background: Despite continuous efforts, the treatment of canine cancer has still to deliver effective strategies. For example, traditional chemotherapy with doxorubicin and/or docetaxel does not significantly increase survival in dogs with canine mammary tumors (CMTs). Aims: Evaluate the efficiency of two metal compounds [Zn(DION)2]Cl (TS26

2015
Heterocyclic anticancer compounds: Recent advances and the paradigm shift towards the use of nanomedicine's tool Box, Martins, Pedro, Jesus Joao, Santos Sofia, Raposo {Luis R. }, Roma-Rodrigues Catarina, Baptista {Pedro Miguel Ribeiro Viana}, and de Fernandes {Maria Alexandra Núncio Carvalho Ramos} , Molecules, sep, Volume 20, Number 9, p.16852–16891, (2015) Abstract

The majority of heterocycle compounds and typically common heterocycle fragments present in most pharmaceuticals currently marketed, alongside with their intrinsic versatility and unique physicochemical properties, have poised them as true cornerstones of medicinal chemistry. Apart from the already marketed drugs, there are many other being investigated for their promising activity against several malignancies. In particular, anticancer research has been capitalizing on the intrinsic versatility and dynamic core scaffold of these compounds. Nevertheless, as for any other promising anticancer drugs, heterocyclic compounds do not come without shortcomings. In this review, we provide for a concise overview of heterocyclic active compounds and families and their main applications in medicine. We shall focus on those suitable for cancer therapy while simultaneously addressing main biochemical modes of action, biological targets, structure-activity relationships as well as intrinsic limitation issues in the use of these compounds. Finally, considering the advent of nanotechnology for effective selective targeting of drugs, we shall discuss fundamental aspects and considerations on nanovectorization of such compounds that may improve pharmacokinetic/pharmacodynamic properties of heterocycles.

2014
A low cost, safe, disposable, rapid and self-sustainable paper-based platform for diagnostic testing: Lab-on-paper, Costa, {Mafalda Nascimento}, Veigas Bruno, Jacob {Jorge M. }, Santos {David S. }, Gomes Jacinto, Baptista {Pedro Viana}, Martins Rodrigo, Inácio João, and Fortunato Elvira , Nanotechnology, mar, Volume 25, Number 9, (2014) Abstract

There is a strong interest in the use of biopolymers in the electronic and biomedical industries, mainly towards low-cost applications. The possibility of developing entirely new kinds of products based on cellulose is of current interest, in order to enhance and to add new functionalities to conventional paper-based products. We present our results towards the development of paper-based microfluidics for molecular diagnostic testing. Paper properties were evaluated and compared to nitrocellulose, the most commonly used material in lateral flow and other rapid tests. Focusing on the use of paper as a substrate for microfluidic applications, through an eco-friendly wax-printing technology, we present three main and distinct colorimetric approaches: (i) enzymatic reactions (glucose detection); (ii) immunoassays (antibodies anti-Leishmania detection); (iii) nucleic acid sequence identification (Mycobacterium tuberculosis complex detection). Colorimetric glucose quantification was achieved through enzymatic reactions performed within specific zones of the paper-based device. The colouration achieved increased with growing glucose concentration and was highly homogeneous, covering all the surface of the paper reaction zones in a 3D sensor format. These devices showed a major advantage when compared to the 2D lateral flow glucose sensors, where some carryover of the coloured products usually occurs. The detection of anti-Leishmania antibodies in canine sera was conceptually achieved using a paper-based 96-well enzyme-linked immunosorbent assay format. However, optimization is still needed for this test, regarding the efficiency of the immobilization of antigens on the cellulose fibres. The detection of Mycobacterium tuberculosis nucleic acids integrated with a non-cross-linking gold nanoprobe detection scheme was also achieved in a wax-printed 384-well paper-based microplate, by the hybridization with a species-specific probe. The obtained results with the above-mentioned proof-of-concept sensors are thus promising towards the future development of simple and cost-effective paper-based diagnostic devices.

2013
Invivo tumor targeting via nanoparticle-mediated therapeutic siRNA coupled to inflammatory response in lung cancer mouse models, Conde, João, Tian Furong, Hernández Yulán, Bao Chenchen, Cui Daxiang, Janssen {Klaus Peter}, Ibarra Ricardo} {M., Baptista {Pedro V. }, Stoeger Tobias, and {de la Fuente} {Jesús M. } , Biomaterials, oct, Volume 34, Number 31, p.7744–7753, (2013) Abstract

Up to now, functionalized gold nanoparticles have been optimized as an effective intracellular invitro delivery vehicle for siRNAs to interfere with the expression of specific genes by selective targeting, and provide protection against nucleases. Few examples however of suchlike invivo applications have been described so far. In this study, we report the use of siRNA/RGD gold nanoparticles capable of targeting tumor cells in a lung cancer syngeneic orthotopic murine model. Therapeutic RGD-nanoparticle treatment resulted in successful targeting evident from significant c-myc oncogene down-regulation followed by tumor growth inhibition and prolonged survival of lung tumor bearing mice, possibly via αvβ3 integrin interaction. Our results suggest that RGD gold nanoparticles-mediated delivery of siRNA by intratracheal instillation in mice leads to successful suppression of tumor cell proliferation and respective tumor size reduction. These results reiterate the capability of functionalized gold nanoparticles for targeted delivery of siRNA to cancer cells towards effective silencing of the specific target oncogene. What is more, we demonstrate that the gold-nanoconjugates trigger a complex inflammatory and immune response that might promote the therapeutic effect of the RNAi to reduce tumor size with low doses of siRNA.

2012
Gold on paper-paper platform for Au-nanoprobe TB detection, Veigas, {Bruno Miguel Ribeiro}, Jacob {Jorge Alexandre Marmelo}, Costa {Mafalda N. }, de Santos {David Pena Sousa}, Bettencourt {Miguel Viveiros}, Inácio João, de Martins {Rodrigo Ferrão Paiva}, Barquinha {Pedro Miguel Cândido}, Fortunato {Elvira Maria Correia}, and Baptista {Pedro Miguel Ribeiro Viana} , Lab On A Chip, nov, Volume 12, Number 22, p.4802–8, (2012) Abstract

Tuberculosis (TB) remains one of the most serious infectious diseases in the world and the rate of new cases continues to increase. The development of cheap and simple methodologies capable of identifying TB causing agents belonging to the Mycobacterium tuberculosis Complex (MTBC), at point-of-need, in particular in resource-poor countries where the main TB epidemics are observed, is of paramount relevance for the timely and effective diagnosis and management of patients. TB molecular diagnostics, aimed at reducing the time of laboratory diagnostics from weeks to days, still require specialised technical personnel and labour intensive methods. Recent nanotechnology-based systems have been proposed to circumvent these limitations. Here, we report on a paper-based platform capable of integrating a previously developed Au-nanoprobe based MTBC detection assay-we call it {"}Gold on Paper{"}. The Au-nanoprobe assay is processed and developed on a wax-printed microplate paper platform, allowing unequivocal identification of MTBC members and can be performed without specialised laboratory equipment. Upon integration of this Au-nanoprobe colorimetric assay onto the 384-microplate, differential colour scrutiny may be captured and analysed with a generic {"}smartphone{"} device. This strategy uses the mobile device to digitalise the intensity of the colour associated with each colorimetric assay, perform a Red Green Blue (RGB) analysis and transfer relevant information to an off-site lab, thus allowing for efficient diagnostics. Integration of the GPS location metadata of every test image may add a new dimension of information, allowing for real-time epidemiologic data on MTBC identification.

1998
Bacterial contig map of the 21q11 region associated with Alzheimer's disease and abnormal myelopoiesis in Down syndrome, GROET, J., Ives {J. H. }, South {A. P. }, Baptista {P. R. }, Jones {T. A. }, Yaspo {M. L. }, Lehrach H., Potier {M. C. }, {Van Broeckhoven} C., and Nizetic D. , Genome Research, jan, Volume 8, Number 4, p.385–398, (1998) Abstract

We present a high-resolution bacterial contig map of 3.4 Mb of genomic DNA in human chromosome 21q11-q21, encompassing the region of elevated disomic homozygosity in Down Syndrome-associated abnormal myelopoiesis and leukemia, as well as the markers, which has shown a strong association with Alzheimer's Disease that has never been explained. The map contains 89 overlapping PACs, BACs, or cosmids in three contigs (850, 850, and 1500 kb) with two gaps (one of 140-210 kb and the second < 5 kb). To date, eight transcribed sequences derived by cDNA selection, exon trapping, and/or global EST sequencing have been positioned onto the map, and the only two genes so far mapped to this cytogenetic region, STCH and RIP140 have been precisely localized. This work converts a further 10% of chromosome 21q into a high-resolution bacterial contig map, which will be the physical basis for the long-range sequencing of this region. The map will also enable positional derivation of new transcribed sequences, as well as new polymorphic probes, that will help in elucidation of the role the genes in this region may play in abnormal myelopoiesis and leukemia associated with trisomy 21 and Alzheimer's Disease.