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Dr. Miguel Santos
LAQV-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal

Basic Info


Research Keywords & Expertise

0 Bioavailability
0 Ionic Liquids
0 Organic Chemistry
0 Polymorphism
0 Pharmaceutical Chemistry

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Ionic Liquids
Bioavailability
Polymorphism
Active Pharmaceutical Ingredients as Ionic Liquids

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Project

Project Goal: This project aims to develop novel ionic formulations of repurposed drugs with known activity against SARS-CoV-2 in order to enhance their bioavailability and therapeutic activity while decreasing associated toxicity

Starting Date:06 July 2020

Current Stage: ongoing

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Review
Published: 07 June 2021 in Surfaces
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Antiseptics and disinfectants are extensively used for a variety of topical and hard-surface applications. A wide variety of biocides as active chemical agents is found in these products, including alcohols, phenols, iodine, and chlorine. Many of these active agents demonstrate broad-spectrum antimicrobial activity; however, the mode of action of these agents is not well-documented. This review is focused on several examples of ionic systems based on ionic surfactants and ionic liquids as well as nanomaterials and nanoparticles acting as antiseptics and disinfectants for surfaces. It is important to note that many of these biocides may be used singly or in combination in a variety of products, which vary considerably in activity against microorganisms. Antimicrobial activity can be influenced by several factors such as formulation effects, presence of an organic load, synergy, temperature, dilution, and test method. The most promissory compounds based on ionic systems and nanomaterials published in mainly the last decade is chronologically reported in this review.

ACS Style

Francisco Faísca; Luis Filipe; Zeljko Petrovski; Miguel Santos; Sandra Gago; Luís Branco. Ionic Systems and Nanomaterials as Antiseptic and Disinfectant Agents for Surface Applications: A Review. Surfaces 2021, 4, 169 -190.

AMA Style

Francisco Faísca, Luis Filipe, Zeljko Petrovski, Miguel Santos, Sandra Gago, Luís Branco. Ionic Systems and Nanomaterials as Antiseptic and Disinfectant Agents for Surface Applications: A Review. Surfaces. 2021; 4 (2):169-190.

Chicago/Turabian Style

Francisco Faísca; Luis Filipe; Zeljko Petrovski; Miguel Santos; Sandra Gago; Luís Branco. 2021. "Ionic Systems and Nanomaterials as Antiseptic and Disinfectant Agents for Surface Applications: A Review." Surfaces 4, no. 2: 169-190.

Journal article
Published: 05 February 2021 in Pharmaceutics
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Mesoporous silica nanoparticles (MSNs) are very promising nanomaterials for treating bacterial infections when combined with pharmaceutical drugs. Herein, we report the preparation of two nanomaterials based on the immobilization of ciprofloxacin in mesoporous silica nanoparticles, either as the counter-ion of the choline derivative cation (MSN-[Ch][Cip]) or via anchoring on the surface of amino-group modified MSNs via an amide bond (MSN-Cip). Both nanomaterials were characterized by TEM, FTIR and solution 1H NMR spectroscopies, elemental analysis, XRD and N2 adsorption at 77 K in order to provide the desired structures. No cytotoxicity from the prepared mesoporous nanoparticles on 3T3 murine fibroblasts was observed. The antimicrobial activity of the nanomaterials was determined against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Klebsiella pneumoniae) bacteria and the results were promising against S. aureus. In the case of B. subtilis, both nanomaterials exhibited higher antimicrobial activity than the precursor [Ch][Cip], and in the case of K. pneumoniae they exhibited higher activity than neutral ciprofloxacin.

ACS Style

Blanca De Juan Mora; Luís Filipe; Andreia Forte; Miguel Santos; Celso Alves; Fernando Teodoro; Rui Pedrosa; Manuela Ribeiro Carrott; Luís Branco; Sandra Gago. Boosting Antimicrobial Activity of Ciprofloxacin by Functionalization of Mesoporous Silica Nanoparticles. Pharmaceutics 2021, 13, 218 .

AMA Style

Blanca De Juan Mora, Luís Filipe, Andreia Forte, Miguel Santos, Celso Alves, Fernando Teodoro, Rui Pedrosa, Manuela Ribeiro Carrott, Luís Branco, Sandra Gago. Boosting Antimicrobial Activity of Ciprofloxacin by Functionalization of Mesoporous Silica Nanoparticles. Pharmaceutics. 2021; 13 (2):218.

Chicago/Turabian Style

Blanca De Juan Mora; Luís Filipe; Andreia Forte; Miguel Santos; Celso Alves; Fernando Teodoro; Rui Pedrosa; Manuela Ribeiro Carrott; Luís Branco; Sandra Gago. 2021. "Boosting Antimicrobial Activity of Ciprofloxacin by Functionalization of Mesoporous Silica Nanoparticles." Pharmaceutics 13, no. 2: 218.

Proceedings
Published: 01 December 2020 in Proceedings
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The majority of antibiotics display low oral bioavailability due to reduced solubility in water and/or inefficient permeability across biological membranes. Their efficiency is further limited by the frequent presence of polymorphic structures with different pharmaceutical activities. In this communication, we present our latest results on the development of organic salts and ionic liquids from fluoroquinolones (FQ-OSILs) as highly efficient ionic formulations of this family of antimicrobials. Ciprofloxacin and norfloxacin were used as anions and as cations, by combination with biocompatible organic counter-ions. In vitro bioavailability studies showed that all prepared FQ-OSILs presented higher solubility in water than the original drugs. All compounds were found to be isomorphic and with tailorable antimicrobial activity according to the cation–anion combination against Staphylococcus aureus, Bacillus subtilis and Klebsiella pneumoniae strains.

ACS Style

Diogo Madeira; Celso Alves; Joana Silva; Catarina Florindo; Alexandra Costa; Željko Petrovski; Isabel Marrucho; Rui Pedrosa; Miguel Santos; Luís Branco. Fluoroquinolone-Based Organic Salts and Ionic Liquids as Highly Bioavailable Broad-Spectrum Antimicrobials. Proceedings 2020, 78, 3 .

AMA Style

Diogo Madeira, Celso Alves, Joana Silva, Catarina Florindo, Alexandra Costa, Željko Petrovski, Isabel Marrucho, Rui Pedrosa, Miguel Santos, Luís Branco. Fluoroquinolone-Based Organic Salts and Ionic Liquids as Highly Bioavailable Broad-Spectrum Antimicrobials. Proceedings. 2020; 78 (1):3.

Chicago/Turabian Style

Diogo Madeira; Celso Alves; Joana Silva; Catarina Florindo; Alexandra Costa; Željko Petrovski; Isabel Marrucho; Rui Pedrosa; Miguel Santos; Luís Branco. 2020. "Fluoroquinolone-Based Organic Salts and Ionic Liquids as Highly Bioavailable Broad-Spectrum Antimicrobials." Proceedings 78, no. 1: 3.

Editorial
Published: 23 September 2020 in Pharmaceutics
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Over the last few decades, Ionic Liquids (ILs) and Deep Eutectic Solvents (DES) have been studied academically throughout many fields of chemical and biological research, including pharmaceutical sciences, due to their highly tunable physical, chemical and physicochemical properties

ACS Style

Miguel M. Santos; Luís C. Branco. Ionic Liquids and Deep Eutectic Solvents for Application in Pharmaceutics. Pharmaceutics 2020, 12, 909 .

AMA Style

Miguel M. Santos, Luís C. Branco. Ionic Liquids and Deep Eutectic Solvents for Application in Pharmaceutics. Pharmaceutics. 2020; 12 (10):909.

Chicago/Turabian Style

Miguel M. Santos; Luís C. Branco. 2020. "Ionic Liquids and Deep Eutectic Solvents for Application in Pharmaceutics." Pharmaceutics 12, no. 10: 909.

Journal article
Published: 22 September 2020 in Biosensors
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A new fluorescent chemosensor for copper (II) and subsequent anion sensing was designed and fully characterized. The sensor consisted of a 1,8-naphthalimide core, bearing two terminal dipicolylamine (DPA) receptor units for binding metal cations, and an ethoxyethanol moiety for enhanced water solubility. The DPA units are connected to position 4 of the fluorophore via a triazine-ethylenediamine spacer. Fluorescence titration studies of the chemosensor revealed a high selectivity for Cu2+ over other divalent ions, the emissions were strongly quenched upon binding, and a stability constant of 5.52 log units was obtained. Given the distance from DPA chelating units and the fluorophore, quenching from the Cu2+ complexation suggests an electron transfer or an electronic energy transfer mechanism. Furthermore, the Cu2+-sensor complex proved to be capable of sensing anionic phosphate derivatives through the displacement of the Cu2+ cation, which translated into a full recovery of the luminescence from the naphthalimide. Super-resolution fluorescence microscopy studies performed in HeLa cells showed there was a high intracellular uptake of the chemosensor. Incubation in Cu2+ spiked media revealed a strong fluorescent signal from mitochondria and cell membranes, which is consistent with a high concentration of ATP at these intracellular sites.

ACS Style

Artur Moro; Miguel Santos; Mani Outis; Pedro Mateus; Pedro Pereira. Selective Coordination of Cu2+ and Subsequent Anion Detection Based on a Naphthalimide-Triazine-(DPA)2 Chemosensor. Biosensors 2020, 10, 129 .

AMA Style

Artur Moro, Miguel Santos, Mani Outis, Pedro Mateus, Pedro Pereira. Selective Coordination of Cu2+ and Subsequent Anion Detection Based on a Naphthalimide-Triazine-(DPA)2 Chemosensor. Biosensors. 2020; 10 (9):129.

Chicago/Turabian Style

Artur Moro; Miguel Santos; Mani Outis; Pedro Mateus; Pedro Pereira. 2020. "Selective Coordination of Cu2+ and Subsequent Anion Detection Based on a Naphthalimide-Triazine-(DPA)2 Chemosensor." Biosensors 10, no. 9: 129.

Journal article
Published: 23 July 2020 in Pharmaceutics
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As the development of novel antibiotics has been at a halt for several decades, chemically enhancing existing drugs is a very promising approach to drug development. Herein, we report the preparation of twelve organic salts and ionic liquids (OSILs) from ciprofloxacin and norfloxacin as anions with enhanced antimicrobial activity. Each one of the fluoroquinolones (FQs) was combined with six different organic hydroxide cations in 93–100% yield through a buffer-assisted neutralization methodology. Six of those were isomorphous salts while the remaining six were ionic liquids, with four of them being room temperature ionic liquids. The prepared compounds were not toxic to healthy cell lines and displayed between 47- and 1416-fold more solubility in water at 25 and 37 °C than the original drugs, with the exception of the ones containing the cetylpyridinium cation. In general, the antimicrobial activity against Klebsiella pneumoniae was particularly enhanced for the ciprofloxacin-based OSILs, with up to ca. 20-fold decreases of the inhibitory concentrations in relation to the parent drug, while activity against Staphylococcus aureus and the commensal Bacillus subtilis strain was often reduced. Depending on the cation–drug combination, broad-spectrum or strain-specific antibiotic salts were achieved, potentially leading to the future development of highly bioavailable and safe antimicrobial ionic formulations.

ACS Style

Miguel Santos; Celso Alves; Joana Silva; Catarina Florindo; Alexandra Costa; Željko Petrovski; Isabel Marrucho; Rui Pedrosa; Luís Branco. Antimicrobial Activities of Highly Bioavailable Organic Salts and Ionic Liquids from Fluoroquinolones. Pharmaceutics 2020, 12, 694 .

AMA Style

Miguel Santos, Celso Alves, Joana Silva, Catarina Florindo, Alexandra Costa, Željko Petrovski, Isabel Marrucho, Rui Pedrosa, Luís Branco. Antimicrobial Activities of Highly Bioavailable Organic Salts and Ionic Liquids from Fluoroquinolones. Pharmaceutics. 2020; 12 (8):694.

Chicago/Turabian Style

Miguel Santos; Celso Alves; Joana Silva; Catarina Florindo; Alexandra Costa; Željko Petrovski; Isabel Marrucho; Rui Pedrosa; Luís Branco. 2020. "Antimicrobial Activities of Highly Bioavailable Organic Salts and Ionic Liquids from Fluoroquinolones." Pharmaceutics 12, no. 8: 694.

Journal article
Published: 24 March 2020 in Pharmaceutics
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Herein the quantitative synthesis of eight new mono- and dianionic Organic Salts and Ionic Liquids (OSILs) from alendronic acid (ALN) is reported by following two distinct sustainable and straightforward methodologies, according to the type of cation. The prepared ALN-OSILs were characterized by spectroscopic techniques and their solubility in water and biological fluids was determined. An evaluation of the toxicity towards human healthy cells and also human breast, lung and bone (osteosarcoma) cell lines was performed. Globally, it was observed that the monoanionic OSILs showed lower toxicity than the corresponding dianionic structures to all cell types. The highest cytotoxic effect was observed in OSILs containing a [C2OHMIM] cation, in particular [C2OHMIM][ALN]. The latter showed an improvement in IC50 values of ca. three orders of magnitude for the lung and bone cancer cell lines as well as fibroblasts in comparison with ALN. The development of OSILs with high cytotoxicity effect towards the tested cancer cell types, and containing an anti-resorbing molecule such as ALN may represent a promising strategy for the development of new pharmacological tools to be used in those pathological conditions.

ACS Style

Sónia Teixeira; Miguel M. Santos; Maria H. Fernandes; João Costa-Rodrigues; Luís C. Branco. Alendronic Acid as Ionic Liquid: New Perspective on Osteosarcoma. Pharmaceutics 2020, 12, 293 .

AMA Style

Sónia Teixeira, Miguel M. Santos, Maria H. Fernandes, João Costa-Rodrigues, Luís C. Branco. Alendronic Acid as Ionic Liquid: New Perspective on Osteosarcoma. Pharmaceutics. 2020; 12 (3):293.

Chicago/Turabian Style

Sónia Teixeira; Miguel M. Santos; Maria H. Fernandes; João Costa-Rodrigues; Luís C. Branco. 2020. "Alendronic Acid as Ionic Liquid: New Perspective on Osteosarcoma." Pharmaceutics 12, no. 3: 293.

Journal article
Published: 02 March 2020 in Pharmaceutics
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The preparation and characterization of ionic liquids and organic salts (OSILs) that contain anionic penicillin G [secoPen] and amoxicillin [seco-Amx] hydrolysate derivatives and their in vitro antibacterial activity against sensitive and resistant Escherichia coli and Staphylococcus aureus strains is reported. Eleven hydrolyzed β-lactam-OSILs were obtained after precipitation in moderate-to-high yields via the neutralization of the basic ammonia buffer of antibiotics with different cation hydroxide salts. The obtained minimum inhibitory concentration (MIC) data of the prepared compounds showed a relative decrease of the inhibitory concentrations (RDIC) in the order of 100 in the case of [C2OHMIM][seco-Pen] against sensitive S. aureus ATCC25923 and, most strikingly, higher than 1000 with [C16Pyr][seco-Amx] against methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300. These outstanding in vitro results showcase that a straightforward transformation of standard antibiotics into hydrolyzed organic salts can dramatically change the pharmaceutical activity of a drug, including giving rise to potent formulations of antibiotics against deadly bacteria strains.

ACS Style

Ricardo Ferraz; Dário Silva; Ana Rita Dias; Vitorino Dias; Miguel M. Santos; Luís Pinheiro; Cristina Prudêncio; João Paulo Noronha; Željko Petrovski; Luís C. Branco. Synthesis and Antibacterial Activity of Ionic Liquids and Organic Salts Based on Penicillin G and Amoxicillin hydrolysate Derivatives against Resistant Bacteria. Pharmaceutics 2020, 12, 221 .

AMA Style

Ricardo Ferraz, Dário Silva, Ana Rita Dias, Vitorino Dias, Miguel M. Santos, Luís Pinheiro, Cristina Prudêncio, João Paulo Noronha, Željko Petrovski, Luís C. Branco. Synthesis and Antibacterial Activity of Ionic Liquids and Organic Salts Based on Penicillin G and Amoxicillin hydrolysate Derivatives against Resistant Bacteria. Pharmaceutics. 2020; 12 (3):221.

Chicago/Turabian Style

Ricardo Ferraz; Dário Silva; Ana Rita Dias; Vitorino Dias; Miguel M. Santos; Luís Pinheiro; Cristina Prudêncio; João Paulo Noronha; Željko Petrovski; Luís C. Branco. 2020. "Synthesis and Antibacterial Activity of Ionic Liquids and Organic Salts Based on Penicillin G and Amoxicillin hydrolysate Derivatives against Resistant Bacteria." Pharmaceutics 12, no. 3: 221.

Conference paper
Published: 12 November 2019 in Proceedings of 5th International Electronic Conference on Medicinal Chemistry
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Bacterial resistance to current antibiotics has a major impact on worldwide human health, leading to 700K deaths every year. The development of novel antibiotics did not present significant progress, namely regarding clinical trials, over the last years due to low returns. Thus, innovative alternatives must be devised to tackle the continuous rise of antimicrobial resistance. Ionic Liquids and Organic Salts from Active Pharmaceutical Ingredients (API-OSILs) have risen in academia for over 10 years as an efficient formulation for drugs with low bioavailability and permeability, as well as reduction or elimination of polymorphism, thereby potentially enhancing their pharmaceutical efficiency. To the best of our knowledge, our group is the first to perform research on the development of API-OSILs from antibiotics as a way to improve their efficiency. More specifically, we have successfully combined ampicillin, penicillin and amoxicillinas anions with biocompatible organic cations such as choline, alkylpyridiniums and alkylimidazoliums. Furthermore, we have also combined fluoroquinolones (ciprofloxacin and norfloxacin) as cations with biocompatible carboxylic and sulfonic acids. In this communication, we present our latest developments in the synthesis and spectroscopic (NMR, FTIR) and physicochemical (DSC) characterization of ionic liquids and organic salts from these antibiotics, in addition to in vitro antimicrobial activity data, in particular towards Methicillin Resistant Staphylococcus aureus and multi-resistant Escherichia coli, as well as sensitive strains of gram-positive and gram-negative bacteria.

ACS Style

Miguel Santos; Inês Grilo; Ricardo Ferraz; Diogo Madeira; Bárbara Soares; Núria Inácio; Luís Pinheiro; Zeljko Petrovski; Cristina Prudêncio; Rita Sobral; Luís Branco. Tackling bacterial resistance using antibiotics as ionic liquids and organic salts. Proceedings of 5th International Electronic Conference on Medicinal Chemistry 2019, 1 .

AMA Style

Miguel Santos, Inês Grilo, Ricardo Ferraz, Diogo Madeira, Bárbara Soares, Núria Inácio, Luís Pinheiro, Zeljko Petrovski, Cristina Prudêncio, Rita Sobral, Luís Branco. Tackling bacterial resistance using antibiotics as ionic liquids and organic salts. Proceedings of 5th International Electronic Conference on Medicinal Chemistry. 2019; ():1.

Chicago/Turabian Style

Miguel Santos; Inês Grilo; Ricardo Ferraz; Diogo Madeira; Bárbara Soares; Núria Inácio; Luís Pinheiro; Zeljko Petrovski; Cristina Prudêncio; Rita Sobral; Luís Branco. 2019. "Tackling bacterial resistance using antibiotics as ionic liquids and organic salts." Proceedings of 5th International Electronic Conference on Medicinal Chemistry , no. : 1.

Communication
Published: 26 September 2019 in ChemMedChem
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Novel ionic liquids and organic salts based on mono‐ or dianionic zoledronate and protonated superbases, choline and n‐alkylmethylimidazolium cations, were prepared and characterized by spectroscopic and thermal analyses. Most of the prepared salts display amorphous structures and very high solubility in water and saline solutions, especially the dianionic salts. Among the zoledronate‐based ionic compounds, those containing choline [Ch] and methoxyethylmethylimidazolium [C3OMIM] cations appear to have significant cytotoxicity against human osteosarcoma cells (MG63) and low toxicity toward healthy skin fibroblast cells. Because osteosarcoma is a bone pathology characterized by an increase in bone turnover rate, the results presented herein may be a promising starting point for the development of new ionic pharmaceutical drugs against osteosarcoma.

ACS Style

Sónia Teixeira; Miguel M. Santos; Ricardo Ferraz; Cristina Prudêncio; Maria H. Fernandes; João Costa‐Rodrigues; Luís C. Branco. A Novel Approach for Bisphosphonates: Ionic Liquids and Organic Salts from Zoledronic Acid. ChemMedChem 2019, 14, 1767 -1770.

AMA Style

Sónia Teixeira, Miguel M. Santos, Ricardo Ferraz, Cristina Prudêncio, Maria H. Fernandes, João Costa‐Rodrigues, Luís C. Branco. A Novel Approach for Bisphosphonates: Ionic Liquids and Organic Salts from Zoledronic Acid. ChemMedChem. 2019; 14 (20):1767-1770.

Chicago/Turabian Style

Sónia Teixeira; Miguel M. Santos; Ricardo Ferraz; Cristina Prudêncio; Maria H. Fernandes; João Costa‐Rodrigues; Luís C. Branco. 2019. "A Novel Approach for Bisphosphonates: Ionic Liquids and Organic Salts from Zoledronic Acid." ChemMedChem 14, no. 20: 1767-1770.

Communication
Published: 08 February 2019 in ChemMedChem
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Herein we report the synthesis of novel ionic liquids (ILs) by combination of Ibuprofen as anion with biocompatible ammonium, imidazolium and pyridinium cations. The synthetic methodology consisted in the acid‐base reaction of neutral Ibuprofen with cation hydroxides, which were previously prepared by anion exchange from the corresponding halide salts with Amberlyst A‐26(OH). In comparison with the parent drug, the plethora of synthesized compounds display very attractive physicochemical properties such as higher solubility in water and biological fluids and a smaller degree of polymorphism which in some cases was completely eliminated. With the exception of [C16Pyr][Ibu] and [N1,1,2,2OH1][Ibu], the majority of the other salts did not affect the viability of normal human dermal fibroblasts or the viability of ovarian carcinoma (A2780) cell lines. Interestingly, the cytotoxicity of [C16Pyr][Ibu] might be ascribed to its cation, once [C16Pyr]Cl showed IC50 values < 100 and 2.2 ± 0.1 µM for fibroblasts and A2780 cell line, respectively. Thus, in the future these Ibuprofen‐based ionic liquids may be very promising lead candidates for the development of new and highly effective formulations of this drug.

ACS Style

Miguel Santos; Luís Raposo; Gonçalo Carrera; Alexandra Costa; Madalena Dionísio; Pedro Baptista; Alexandra Fernandes; Luís C. Branco. Ionic Liquids and Salts from Ibuprofen as Promising Innovative Formulations of an Old Drug. ChemMedChem 2019, 14, 907 -911.

AMA Style

Miguel Santos, Luís Raposo, Gonçalo Carrera, Alexandra Costa, Madalena Dionísio, Pedro Baptista, Alexandra Fernandes, Luís C. Branco. Ionic Liquids and Salts from Ibuprofen as Promising Innovative Formulations of an Old Drug. ChemMedChem. 2019; 14 (9):907-911.

Chicago/Turabian Style

Miguel Santos; Luís Raposo; Gonçalo Carrera; Alexandra Costa; Madalena Dionísio; Pedro Baptista; Alexandra Fernandes; Luís C. Branco. 2019. "Ionic Liquids and Salts from Ibuprofen as Promising Innovative Formulations of an Old Drug." ChemMedChem 14, no. 9: 907-911.

Research article
Published: 07 May 2018 in The Journal of Physical Chemistry C
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The design, synthesis and photoluminescence characterization of sulfide cluster-based zeolitic materials with the general formula Na8[SiAlO4]6SxCl2–2x is presented in this report. The employed experimental conditions, which included the thermal treatment of sodium Linde type A (Na-LTA) zeolites in the presence of Na2SO4 and NaCl, yielded highly photoluminescent sulfur-zeolites with remarkably large Stokes shifts. An emission band at 650 nm for samples with low sulfur contents is observed when excited at 380 nm, which is fully consistent with S2– clusters as light-emitting centers. These orange emitting materials display external quantum efficiencies (EQEs) reaching 53% with peculiar high temperature photoluminescence stability up to 450 °C. For higher S/Cl molar ratios, a gradual conversion to near-infrared (NIR) light-emitting centers is observed with a maximum at 780 nm. This novel NIR luminescent species with EQEs of about 10% are attributed to polysulfide clusters (tentatively S42– species). Given the high EQE values, large Stokes shifts, and thermal stability, the materials presented in this report can find applications in light down-conversion systems or as phosphors in lighting devices.

ACS Style

Andreia Ruivo; E. Coutino-Gonzalez; Miguel Santos; W. Baekelant; E. Fron; Maarten Roeffaers; F. Pina; J. Hofkens; C.A.T. Laia. Highly Photoluminescent Sulfide Clusters Confined in Zeolites. The Journal of Physical Chemistry C 2018, 122, 14761 -14770.

AMA Style

Andreia Ruivo, E. Coutino-Gonzalez, Miguel Santos, W. Baekelant, E. Fron, Maarten Roeffaers, F. Pina, J. Hofkens, C.A.T. Laia. Highly Photoluminescent Sulfide Clusters Confined in Zeolites. The Journal of Physical Chemistry C. 2018; 122 (26):14761-14770.

Chicago/Turabian Style

Andreia Ruivo; E. Coutino-Gonzalez; Miguel Santos; W. Baekelant; E. Fron; Maarten Roeffaers; F. Pina; J. Hofkens; C.A.T. Laia. 2018. "Highly Photoluminescent Sulfide Clusters Confined in Zeolites." The Journal of Physical Chemistry C 122, no. 26: 14761-14770.

Journal article
Published: 06 June 2017 in New Journal of Chemistry
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Herein a straightforward approach for the enhancement of the water solubility of common antibiotic and NSAID active pharmaceutical ingredients (APIs) is presented. Herein a straightforward approach for the enhancement of the water solubility of common antibiotic and NSAID active pharmaceutical ingredients (APIs) is presented. The APIs are converted into ionic liquids (API-ILs) and molten salts by combination with the organic superbases TMG, DBU and DBN. The prepared superionic liquids were characterized by 1 H and 13 C NMR as well as FTIR spectroscopy and elemental analysis. Most products are amorphous non-polymorphic room temperature ionic liquids with very high solubility in water, which may enhance the bioavailability of the API-ILs in comparison with the parent drugs.

ACS Style

Gonçalo V. S. M. Carrera; Miguel M. Santos; Alexandra Costa; Luis Paulo N. Rebelo; Isabel M. Marrucho; M. Nunes Da Ponte; Luis C. Branco. Highly water soluble room temperature superionic liquids of APIs. New Journal of Chemistry 2017, 41, 6986 -6990.

AMA Style

Gonçalo V. S. M. Carrera, Miguel M. Santos, Alexandra Costa, Luis Paulo N. Rebelo, Isabel M. Marrucho, M. Nunes Da Ponte, Luis C. Branco. Highly water soluble room temperature superionic liquids of APIs. New Journal of Chemistry. 2017; 41 (15):6986-6990.

Chicago/Turabian Style

Gonçalo V. S. M. Carrera; Miguel M. Santos; Alexandra Costa; Luis Paulo N. Rebelo; Isabel M. Marrucho; M. Nunes Da Ponte; Luis C. Branco. 2017. "Highly water soluble room temperature superionic liquids of APIs." New Journal of Chemistry 41, no. 15: 6986-6990.

Review
Published: 15 May 2017 in Mini-Reviews in Medicinal Chemistry
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The recent advances for the synthesis and application of different metallocenes for Medicinal Chemistry is reviewed. This manuscript presents the different metallocene scaffolds, with special emphasis on ferrocene derivatives, and their potential pharmaceutical application. Over the last years, the synthesis of new metallocene compounds and their biological and medicinal effects against some types of diseases (e.g. anti-tumoral, antibiotics, anti-viral) have been reported. From the medicinal point of view, the attractive properties of metallocene derivatives, such as their high stability, low toxicity and appealing redox behaviors are particularly relevant. This area has attracted many researchers as well as the pharmaceutical industry due to the promising results of some metallocenes, in particular ferrocene compounds, in breast cancer and malaria.

ACS Style

Miguel Santos; Pedro Bastos; Isabelle Catela; Karolina Zalewska; Luis Branco. Recent Advances of Metallocenes for Medicinal Chemistry. Mini-Reviews in Medicinal Chemistry 2017, 17, 771 -784.

AMA Style

Miguel Santos, Pedro Bastos, Isabelle Catela, Karolina Zalewska, Luis Branco. Recent Advances of Metallocenes for Medicinal Chemistry. Mini-Reviews in Medicinal Chemistry. 2017; 17 (9):771-784.

Chicago/Turabian Style

Miguel Santos; Pedro Bastos; Isabelle Catela; Karolina Zalewska; Luis Branco. 2017. "Recent Advances of Metallocenes for Medicinal Chemistry." Mini-Reviews in Medicinal Chemistry 17, no. 9: 771-784.

Book chapter
Published: 28 September 2016 in Recent Advances in Organocatalysis
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ACS Style

Karolina Zalewska; Miguel M. Santos; Hugo Cruz; Luis C. Branco. Photo-Organocatalysis, Photo-Redox, and Electro- Organocatalysis Processes. Recent Advances in Organocatalysis 2016, 1 .

AMA Style

Karolina Zalewska, Miguel M. Santos, Hugo Cruz, Luis C. Branco. Photo-Organocatalysis, Photo-Redox, and Electro- Organocatalysis Processes. Recent Advances in Organocatalysis. 2016; ():1.

Chicago/Turabian Style

Karolina Zalewska; Miguel M. Santos; Hugo Cruz; Luis C. Branco. 2016. "Photo-Organocatalysis, Photo-Redox, and Electro- Organocatalysis Processes." Recent Advances in Organocatalysis , no. : 1.

Communication
Published: 16 July 2015 in ChemMedChem
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Significant antiproliferative effects against various tumor cell lines were observed with novel ampicillin salts as ionic liquids. The combination of anionic ampicillin with appropriate ammonium, imidazolium, phosphonium, and pyridinium cations yielded active pharmaceutical ingredient ionic liquids (API‐ILs) that show potent antiproliferative activities against five different human cancer cell lines: T47D (breast), PC3 (prostate), HepG2 (liver), MG63 (osteosarcoma), and RKO (colon). Some API‐ILs showed IC50 values between 5 and 42 nM, activities that stand in dramatic contrast to the negligible cytotoxic activity level shown by the ampicillin sodium salt. Moreover, very low cytotoxicity against two primary cell lines—skin (SF) and gingival fibroblasts (GF)—indicates that the majority of these API‐ILs are nontoxic to normal human cell lines. The most promising combination of antitumor activity and low toxicity toward healthy cells was observed for the 1‐hydroxyethyl‐3‐methylimidazolium–ampicillin pair ([C2OHMIM][Amp]), making this the most suitable lead API‐IL for future studies.

ACS Style

Ricardo Ferraz; João Costa-Rodrigues; Maria Helena Fernandes; Miguel Santos; Isabel Marrucho; Luis Paulo Rebelo; Cristina Prudêncio; João Paulo Noronha; Željko Petrovski; Luís C. Branco. Antitumor Activity of Ionic Liquids Based on Ampicillin. ChemMedChem 2015, 10, 1480 -1483.

AMA Style

Ricardo Ferraz, João Costa-Rodrigues, Maria Helena Fernandes, Miguel Santos, Isabel Marrucho, Luis Paulo Rebelo, Cristina Prudêncio, João Paulo Noronha, Željko Petrovski, Luís C. Branco. Antitumor Activity of Ionic Liquids Based on Ampicillin. ChemMedChem. 2015; 10 (9):1480-1483.

Chicago/Turabian Style

Ricardo Ferraz; João Costa-Rodrigues; Maria Helena Fernandes; Miguel Santos; Isabel Marrucho; Luis Paulo Rebelo; Cristina Prudêncio; João Paulo Noronha; Željko Petrovski; Luís C. Branco. 2015. "Antitumor Activity of Ionic Liquids Based on Ampicillin." ChemMedChem 10, no. 9: 1480-1483.

Journal article
Published: 08 April 2015 in RSC Advances
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Chiral amino-acids in the presence of an organic superbase in a CO2 atmosphere were used to prepare carbamate-based ionic liquids and molten salts. Variation of the superbase and amino acid R-group gave tuneable CO2 release temperatures from the products.

ACS Style

Gonçalo V. S. M. Carrera; Noémi Jordão; Miguel M. Santos; Manuel Nunes Da Ponte; Luís C. Branco. Reversible systems based on CO2, amino-acids and organic superbases. RSC Advances 2015, 5, 35564 -35571.

AMA Style

Gonçalo V. S. M. Carrera, Noémi Jordão, Miguel M. Santos, Manuel Nunes Da Ponte, Luís C. Branco. Reversible systems based on CO2, amino-acids and organic superbases. RSC Advances. 2015; 5 (45):35564-35571.

Chicago/Turabian Style

Gonçalo V. S. M. Carrera; Noémi Jordão; Miguel M. Santos; Manuel Nunes Da Ponte; Luís C. Branco. 2015. "Reversible systems based on CO2, amino-acids and organic superbases." RSC Advances 5, no. 45: 35564-35571.

Journals
Published: 06 January 2015 in Organic & Biomolecular Chemistry
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The binding affinity of a dichlorocalix[2]arene[2]triazine based bis-urea azamacrocycle was investigated towards a wide range of bio-relevant dicarboxylate anions by a combination of 1H NMR titrations in CDCl3 and molecular dynamics simulations.

ACS Style

Miguel Santos; Igor Marques; Silvia Carvalho; Cristina Moiteiro; Vítor Félix. Recognition of bio-relevant dicarboxylate anions by an azacalix[2]arene[2]triazine derivative decorated with urea moieties. Organic & Biomolecular Chemistry 2015, 13, 3070 -3085.

AMA Style

Miguel Santos, Igor Marques, Silvia Carvalho, Cristina Moiteiro, Vítor Félix. Recognition of bio-relevant dicarboxylate anions by an azacalix[2]arene[2]triazine derivative decorated with urea moieties. Organic & Biomolecular Chemistry. 2015; 13 (10):3070-3085.

Chicago/Turabian Style

Miguel Santos; Igor Marques; Silvia Carvalho; Cristina Moiteiro; Vítor Félix. 2015. "Recognition of bio-relevant dicarboxylate anions by an azacalix[2]arene[2]triazine derivative decorated with urea moieties." Organic & Biomolecular Chemistry 13, no. 10: 3070-3085.

Book chapter
Published: 08 April 2010 in Advances in Carbohydrate Chemistry and Biochemistry
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Silicon-based materials, namely zeolites, clays, and silica gel have been widely used in organic synthesis, allowing mild reaction conditions and environmentally friendly methodologies. These heterogeneous catalysts are easy to handle, possess nontoxic and noncorrosive character and offer the possibility of recovery and reuse, thus contributing to clean and sustainable organic transformations. Moreover, they present shape-selective properties and provide stereo- and regiocontrol in chemical reactions. Herein, we survey the most significant applications of silicon-based materials as catalysts in carbohydrate chemistry, to mediate important transformations such as glycosylation, sugar protection and deprotection, and hydrolysis and dehydration. Emphasis is placed on their promising synthetic potential in comparison with conventional catalysts.

ACS Style

Amélia P. Rauter; Nuno M. Xavier; Susana D. Lucas; Miguel Santos. Zeolites and Other Silicon-Based Promoters in Carbohydrate Chemistry. Advances in Carbohydrate Chemistry and Biochemistry 2010, 63, 29 -99.

AMA Style

Amélia P. Rauter, Nuno M. Xavier, Susana D. Lucas, Miguel Santos. Zeolites and Other Silicon-Based Promoters in Carbohydrate Chemistry. Advances in Carbohydrate Chemistry and Biochemistry. 2010; 63 ():29-99.

Chicago/Turabian Style

Amélia P. Rauter; Nuno M. Xavier; Susana D. Lucas; Miguel Santos. 2010. "Zeolites and Other Silicon-Based Promoters in Carbohydrate Chemistry." Advances in Carbohydrate Chemistry and Biochemistry 63, no. : 29-99.