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2011
Martins, R, Nathan A, Barros R, Pereira L\'ıs, Barquinha P, Correia N, Costa R, Ahnood A, Ferreira I, Fortunato E.  2011.  {Complementary metal oxide semiconductor technology with and on paper.}. Advanced materials (Deerfield Beach, Fla.). 23:4491–6., Number 39 AbstractWebsite
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Boavida, N, Moretto SM.  2011.  {Innovation assessment in a local branch of a rail transport manufacture industry - A case study}. , Number 04/2011: Universidade Nova de Lisboa, IET/CICS.NOVA-Interdisciplinary Centre on Social Sciences, Faculty of Science and Technology Abstract

In the context of the revitalization of the Portuguese railway sector with the construction of the high-speed railway network, the working paper proposes an analysis of the results found from the application of an innovation scoring to the Portuguese branch of a global multinational in the railway business. The aim of this exercise is to learn on the innovation management flow between the global corporation and the local branch in Portugal. It also aims to assess the degree of local innovation multinationals generate in view of such type of mega public investments. The working paper is structured in five chapters. In chapter one introduces the innovation scoring tool, instrument of work; chapter two covers the methodology used; the chapter tree presents the case study, subject of research; chapter four presents the findings; and chapter 5 closes with concluding remarks.

Maia, MJ.  2011.  {Innovation scoring no sector de serviços de saúde: um estudo de caso [Innovation scoring in the sector health services: a case study]}. , Number 08/2011: Universidade Nova de Lisboa, IET/CICS.NOVA-Interdisciplinary Centre on Social Sciences, Faculty of Science and Technology Abstract

Nowadays, innovation has been understood as an overall strategy for a company. Thus, it should remain adapted, flexible and responsive to the market changes, where the company operates. For a company to succeed in the innovation process, it should be clear about their position on this issue. There are several dynamic systems of control and management innovation. One of these systems is the Innovation Scoring, developed by COTEC Portugal, a Corporate Association for Innovation supported by the Portuguese government. The Innovation Scoring is a support tool to encourage national companies to develop innovation in a more systematic, efficient and effective way, contributing to the strategic thinking of the company, about their innovation processes. It allows a more indepth knowledge about the different dimensions that sustain innovation processes. It allows also the identification of areas with potential improvement. In order to analyse and diagnose the innovative capabilities of a real organization, have applied the Innovation Scoring survey. One of the Central Hospital in the Greater Lisbon area (Public Business Entity), and more specifically, its Imaging Department was the case studied. Innovation Scoring System is a self-diagnosis survey and therefore self-fulfilled. However, to make the results more reliable and free from bias, it was decided to adapt the application method. Thus, interviews were conducted and the responses were used to complete the questionnaire later on. In the next step, we proceed to result analysis from the point of view of the innovation at the case studied. As a final result, the Hospital Imaging Department received a weighting of 224 in 1000, for the Innovation Index, which means that the Department has much to develop and work, regarding these issues. The results should serve as a basis of motivation and strategic thinking for the Imaging Department, in relation to their innovation processes. This working paper is structured into seven ch

Cândido, AC.  2011.  {Inovação Disruptiva: Reflexões sobre as suas características e implicações no mercado [Disruptive innovation: Reflexions about features and market implications]}. , Number 05/2011: Universidade Nova de Lisboa, IET/CICS.NOVA-Interdisciplinary Centre on Social Sciences, Faculty of Science and Technology Abstract

The study aims at discussing the challenges companies face a highly competitive market, emphasizing the implications of disruptive innovations mainly for companies established in the market. In order to understand the origin of the concept of disruptive innovation, the study also presents the results of network analysis carried out considering the following information: journals in which articles were published, the country of affiliation of the authors, keywords and year of publication. The reflections presented in the study lead us to various conclusions, among them the perception that organizations need more attention to the anticipation of new trends and scenarios in order to fend off the effects of a disruptive innovation introduced.

2010
Moniz, AB.  2010.  Designing a Technology Assessment post-graduation programme: experiences, limits and needs, Sep. , Number 09/2010: Universidade Nova de Lisboa, IET-Research on Enterprise and Work Innovation, Faculty of Science and Technology Abstract

The post-graduation in the field of Technology Assessment (TA) is recent and that are several and different ways to be organised. Most experiences are related with the Masters diplom level (2nd cycle of graduation in high education). Just one in PhD level is explicit in the field of TA, and some other PhD courses include also TA topics in their programme structure. In this chapter we will analyse the problems related with the design of a post-graduation (MA, MSc or PhD) programme in the field of TA using as reference some international experiences. Hereby, the main conclusion seems to address labour market needs in the specialised knowledge of TA, of technology management or technology innovation. In this sense TA should be included as “minor” into post-graduation courses which may range from engineering disciplines to social sciences. As a graduation programme it can fill an expertise gap between technicians,engineers, scientists and the strategic decision makers or policy makers.

Veigas, B, Machado D, Perdigão J, Portugal I, Couto I, Viveiros M, Baptista {PV}.  2010.  Au-nanoprobes for detection of SNPs associated with antibiotic resistance in Mycobacterium tuberculosis, oct. Nanotechnology. 21, Number 41: IOP Publishing Abstract

Tuberculosis (TB) is one of the leading causes of infection in humans, causing high morbility and mortality all over the world. The rate of new cases of multidrug resistant tuberculosis (MDRTB) continues to increase, and since these infections are very difficult to manage, they constitute a serious health problem. In most cases, drug resistance in Mycobacterium tuberculosis has been related to mutations in several loci within the pathogen's genome. The development of fast, cheap and simple screening methodologies would be of paramount relevance for the early detection of these mutations, essential for the timely and effective diagnosis and management of MDRTB patients. The use of gold nanoparticles derivatized with thiol-modified oligonucleotides (Au-nanoprobes) has led to new approaches in molecular diagnostics. Based on the differential non-cross-linking aggregation of Au-nanoprobes, we were able to develop a colorimetric method for the detection of specific sequences and to apply this approach to pathogen identification and single base mutations/single nucleotide polymorphisms (SNP) discrimination. Here we report on the development of Au-nanoprobes for the specific identification of SNPs within the beta subunit of the RNA polymerase (rpoB locus), responsible for resistance to rifampicin in over 95% of rifampicin resistant M. tuberculosis strains.

Raimundo, J, Costa PM, Vale C, Costa MH, Moura I.  2010.  DNA damage and metal accumulation in four tissues of feral Octopus vulgaris from two coastal areas in Portugal, Oct. Ecotoxicology and Environmental Safety. 73:1543-1547., Number 7 AbstractWebsite

The alkaline comet assay has been employed for the first time to estimate the basal DNA damage in the digestive gland, gills, kidney and gonads of Octopus vulgaris. Octopuses were captured in two coastal areas adjacent to the cities of Matosinhos (N) and Olhao (S), Portugal. The area of Matosinhos is influenced by discharges of the Douro River, city of Porto, industries and intensive agriculture, while Olhao is an important fisheries port. Previous works point to contrasting metal availability in the two coastal areas. Among the analysed tissues digestive gland presented the highest levels of Zn, Cu, Cd and Pb. Tissues of specimens from Matosinhos exhibited high levels of Cd and from Olhao enhanced Pb concentrations. The DNA damages in digestive gland, gills and kidney were more accentuated in specimens from Matosinhos than from Olhao, suggesting a stronger effect of contaminants. Elevated strand breakages were registered in digestive gland, recognised for its ability to store and detoxify accumulated metals. The DNA damages in kidney, gills and gonads were lower, reflecting reduced metal accumulation or efficient detoxification. The broad variability of damages in the three tissues may also mirror tissue function, specific defences to genotoxicants and cell-cycle turnover. (C) 2010 Elsevier Inc. All rights reserved.

Batalha, IL, Hussain A, Roque ACA.  2010.  Gum Arabic coated magnetic nanoparticles with affinity ligands specific for antibodies, oct. Journal of Molecular Recognition. 23:462–471., Number 5 AbstractWebsite

A novel magnetic support based on gum Arabic {(GA)} coated iron oxide magnetic nanoparticles {(MNP)} has been endowed with affinity properties towards immunoglobulin G {(IgG)} molecules. The success of the in situ triazine ligand synthesis was confirmed by fluorescence assays. Two synthetic ligands previously developed for binding to {IgG}, named as ligand 22/8 (artificial Protein A) and ligand 8/7 (artificial Protein L) were immobilized on to {MNPs} coated with {GA} {(MNP\_GA).} The dimension of the particles core was not affected by the surface functionalization with {GA} and triazine ligands. The hydrodynamic diameters of the magnetic supports indicate that the coupling of {GA} leads to the formation of larger agglomerates of particles with about 1 microm, but the introduction of the triazine ligands leads to a decrease on {MNPs} size. The non-functionalized {MNP\_GA} bound 28 mg {IgG/g}, two times less than bare {MNP} (60 mg {IgG/g).} {MNP\_GA} modified with ligand 22/8 bound 133 mg {IgG/g} support, twice higher than the value obtained for ligand 8/7 magnetic adsorbents (65 mg/g). Supports modified with ligand 22/8 were selected to study the adsorption and the elution of {IgG.} The adsorption of human {IgG} on this support followed a Langmuir behavior with a Q(máx) of 344 mg {IgG/g} support and K(a) of 1.5 x 10(5) M. The studies on different elution conditions indicated that although the 0.05 M citrate buffer {(pH} 3) presented good recovery yields (elution 64% of bound protein), there was occurrence of iron leaching at this acidic {pH.} Therefore, a potential alternative would be to elute bound protein with a 0.05 M {glycine-NaOH} {(pH} 11) buffer.

Moniz, A, c}as JMC{\c.  2010.  Editorial Note, November. Enterprise and Work Innovation Studies. 6:7-8., Number 6 AbstractWebsite

No abstract is available for this item.

Moniz, A, Cabeças JM.  2010.  {Editorial Note}, November. Enterprise and Work Innovation Studies. 6:7-8., Number 6 AbstractWebsite

No abstract is available for this item.

Carvalho, LC, Estevao MS, Ferreira LM, Fernandes E, Marques MMB.  2010.  A new insight on the hypochlorous acid scavenging mechanism of tryptamine and tryptophan derivatives, NOV 15. BIOORGANIC & MEDICINAL CHEMISTRY LETTERS. 20:6475-6478., Number 22 Abstract
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Estevao, MS, Carvalho LC, Ribeiro D, Couto D, Freitas M, Gomes A, Ferreira LM, Fernandes E, Marques MMB.  2010.  Antioxidant activity of unexplored indole derivatives: Synthesis and screening, NOV. EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY. 45:4869-4878., Number 11 Abstract
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Raimundo, J, Vale C, Duarte R, Moura I.  2010.  Association of Zn, Cu, Cd and Pb with protein fractions and sub-cellular partitioning in the digestive gland of Octopus vulgaris living in habitats with different metal levels, Nov. Chemosphere. 81:1314-1319., Number 10 AbstractWebsite

Zinc Cu Cd and Pb concentrations were determined in protein fractions of digestive gland and in the whole digestive gland of Octopus vulgaris collected from two areas of the Portuguese coast Approximately 95% of Zn 99% of Cu 85-96% of Cd and 77-86% of Pb were stored in the cytosol suggesting the predominance of cytosolic proteins in the trapping these elements Gel filtration chromatography evidenced the presence of two major groups of proteins with high molecular weight (HMW 144 000-130 000 Da) and low molecular weight (LMW 11 000-6000 Da) The following metal-protein associations were found Zn was distributed between HMW and LMW Cu and Cd in LMW proteins with a minor association with HMW and Pb in HMW proteins The strong positive correlations between Cd Zn and Cu and LMW proteins point to the presence of metalloproteins with high affinity to these elements A shift was registered between the maximum of the ratio 254 280 nm and metal concentrations in the chromatographic profiles This shift may result from metallothioneins having a small participation in the metal binding or protein purification was insufficient and various LMW proteins may be interfering (C) 2010 Elsevier Ltd All rights reserved

Silveira, CM, Gomes SP, Araujo AN, Montenegro MC, Todorovic S, Viana AS, Silva RJ, Moura JJ, Almeida MG.  2010.  An efficient non-mediated amperometric biosensor for nitrite determination, May 15. Biosens Bioelectron. 25:2026-32., Number 9 AbstractWebsite

In this paper we propose the construction of a new non-mediated electrochemical biosensor for nitrite determination in complex samples. The device is based on the stable and selective cytochrome c nitrite reductase (ccNiR) from Desulfovibrio desulfuricans, which has both high turnover and heterogeneous electron transfer rates. In opposition to previous efforts making use of several redox mediators, in this work we exploited the capacity of ccNiR to display a direct electrochemical response when interacting with pyrolytic graphite (PG) surfaces. To enable the analytical application of such bioelectrode the protein was successfully incorporated within a porous silica glass made by the sol-gel process. In the presence of nitrite, the ccNiR/sol-gel/PG electrode promptly displays catalytic currents indicating that the entrapped ccNiR molecules are reduced via direct electron transfer. This result is noteworthy since the protein molecules are caged inside a non-conductive silica network, in the absence of any mediator species or electron relay. At optimal conditions, the minimum detectable concentration is 120 nM. The biosensor sensitivity is 430 mA M(-1) cm(-2) within a linear range of 0.25-50 microM, keeping a stable response up to two weeks. The analysis of nitrites in freshwaters using the method of standard addition was highly accurated.

Larguinho, M, Santos {HM }, c}alo Doria G{\c, Scholz H, Baptista {PV}, Capelo {JL }.  2010.  Development of a fast and efficient ultrasonic-based strategy for DNA fragmentation, may. Talanta. 81:881–886., Number 3: Elsevier Abstract

Several ultrasound-based platforms for DNA sample preparation were evaluated in terms of effective fragmentation of DNA (plasmid and genomic DNA)-ultrasonic probe, sonoreactor, ultrasonic bath and the newest Vialtweeter device. The sonoreactor showed the best efficiency of DNA fragmentation while simultaneously assuring no cross-contamination of samples, and was considered the best ultrasonic tool to achieve effective fragmentation of DNA at high-throughput and avoid sample overheating. Several operation variables were studied-ultrasonication time and amplitude, DNA concentration, sample volume and sample pre-treatment-that allowed optimisation of a sonoreactor-based strategy for effective DNA fragmentation. Optimal operating conditions to achieve DNA fragmentation were set to 100% ultrasonic amplitude, 100 μL sample volume, 8 min ultrasonic treatment (2 min/sample) for a DNA concentration of 100 μg mL-1. The proposed ultrasonication strategy can be easily implemented in any laboratory setup, providing fast, simple and reliable means for effective DNA sample preparation when fragmentation is critical for downstream molecular detection and diagnostics protocols.

Santos, A, Duarte AG, Fedorov A, Martinho JMG, Moura I.  2010.  Rubredoxin mutant A51C unfolding dynamics: A Forster Resonance Energy Transfer study, May. Biophysical Chemistry. 148:131-137., Number 1-3 AbstractWebsite

The unfolding dynamics of the rubredoxin mutant A51C (RdA51C) from Desulfovibrio vulgaris (DvRd) was studied on the temperature range from 25 degrees C to 90 degrees C and by incubation at 90 degrees C. By Forster Resonance Energy Transfer (FRET) the donor (D; Trp37) to acceptor (A; 1,5-IAEDANS) distance distribution was probed at several temperatures between 25 degrees C and 90 degrees C, and incubation times at 90 degrees C. From 25 degrees C to 50 degrees C the half-width distributions values (hw) are small and the presence of a discrete D-A distance was considered. At temperatures higher than 60 degrees C broader hw values were observed reflecting the existence of a distance distribution. The protein denaturation was only achieved by heating the solution for 2 h at 90 degrees C, as probed by the increase of the D-A mean distance. From Trp fluorescence it was shown that its vicinity was maintained until similar to 70 degrees C, being the protein hydrodynamic radius invariant until 50 degrees C. However, at similar to 70 degrees C a change in the partial unfolding kinetics indicates the disruption of specific H-bonds occurring in the hydrophobic core. The red shift of 13 nm, observed on the Trp37 emission, confirms the exposition of Trp to solvent after protein incubation at 90 degrees C for 2.5 h. (C) 2010 Elsevier B.V. All rights reserved.

Cardoso, E.  2010.  Classificação automática do sono: contribuição utilizando distância de itakura-saito e wavelets, March. (Arnaldo Batista, Manuel Ortigueira, Rui Rodrigues, Eds.).: FCT-UNL Abstract
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da Silva, DG, de Pinho PG, Pontes H, Ferreira L, Branco P, Remiao F, Carvalho F, Bastos LM, Carmo H.  2010.  Gas chromatography-ion trap mass spectrometry method for the simultaneous measurement of MDMA (ecstasy) and its metabolites, MDA, HMA, and HMMA in plasma and urine, MAR 15. JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES. 878:815-822., Number 9-10 Abstract

The investigation of 3,4-methylenedioxymethamphetamine (MDMA: ecstasy) abuse requires very robust methods with high sensitivity and wide linearity ranges for the quantification of this drug of abuse and its main metabolites in body fluids. An optimized gas chromatography-ion trap mass spectrometry (GC-IT/MS) methodology with electron impact ionization addressing these issues is presented. The sample preparation involves an enzymatic hydrolysis of urine and plasma for conjugate cleavage, a SPE extraction, and a derivatization process. The method was fully validated in rat plasma and urine. Linearity for a wide concentration range was achieved for MDMA, and the metabolites 3,4-methylenedioxyamphetamine (MDA), 4-hydroxy-3-methoxyamphetamine (HMA) and 4-hydroxy-3-methoxymethamphetamine (HMMA). Limits of quantification were 2 ng/mL in plasma and 3.5 ng/mL in urine using a Selected Ion Monitoring detection mode. Selectivity, accuracy, precision, and recovery met the required criteria for the method validation. This GC-IT/MS method provides high sensitivity and adequate performance characteristics for the simultaneous quantification of MDMA, MDA, HMA and HMMA in the studied matrices. (C) 2010 Elsevier B.V. All rights reserved.

Tavares, {JRRF}, Baptista {PMRV}, Doria {GMRPDF}, de Flores {AOL}.  2010.  Colorimetric method and kit for the detection of specific nucleic acid sequences using metal nanoparticles functionalized with modified oligonucleotides, mar. Abstract

The present invention relates to a colorimetric method for the detection of specific nucleic acids sequences, including mutations or single nucleotide polymorphisms within nucleic acid sequences, through the aggregation of nanoparticles functionalized with modified oligonucleotides, induced by an increase of the medium's ionic strength. Another aspect of the present invention relates with the development of a kit based on the method of the present invention, allowing for a quick and easy detection of specific nucleic acids sequences, including mutations or single nucleotide polymorphisms within nucleic acid sequences.

Goodfellow, BJ, Duarte IC, Macedo AL, Volkman BF, Nunes SG, Moura I, Markley JL, Moura JJ.  2010.  An NMR structural study of nickel-substituted rubredoxin, Mar. J Biol Inorg Chem. 15:409-20., Number 3 AbstractWebsite

The Ni(II) and Zn(II) derivatives of Desulfovibrio vulgaris rubredoxin (DvRd) have been studied by NMR spectroscopy to probe the structure at the metal centre. The beta CH(2) proton pairs from the cysteines that bind the Ni(II) atom have been identified using 1D nuclear Overhauser enhancement (NOE) difference spectra and sequence specifically assigned via NOE correlations to neighbouring protons and by comparison with the published X-ray crystal structure of a Ni(II) derivative of Clostridium pasteurianum rubredoxin. The solution structures of DvRd(Zn) and DvRd(Ni) have been determined and the paramagnetic form refined using pseudocontact shifts. The determination of the magnetic susceptibility anisotropy tensor allowed the contact and pseudocontact contributions to the observed chemical shifts to be obtained. Analysis of the pseudocontact and contact chemical shifts of the cysteine H beta protons and backbone protons close to the metal centre allowed conclusions to be drawn as to the geometry and hydrogen-bonding pattern at the metal binding site. The importance of NH-S hydrogen bonds at the metal centre for the delocalization of electron spin density is confirmed for rubredoxins and can be extrapolated to metal centres in Cu proteins: amicyanin, plastocyanin, stellacyanin, azurin and pseudoazurin.

Najmudin, S, Pauleta SR, Moura I, Romao MJ.  2010.  The 1.4 angstrom resolution structure of Paracoccus pantotrophus pseudoazurin, Jun. Acta Crystallographica Section F-Structural Biology and Crystallization Communications. 66:627-635. AbstractWebsite

Pseudoazurins are small type 1 copper proteins that are involved in the flow of electrons between various electron donors and acceptors in the bacterial periplasm, mostly under denitrifying conditions. The previously determined structure of Paracoccus pantotrophus pseudoazurin in the oxidized form was improved to a nominal resolution of 1.4 angstrom, with R and R(free) values of 0.188 and 0.206, respectively. This high-resolution structure makes it possible to analyze the interactions between the monomers and the solvent structure in detail. Analysis of the high-resolution structure revealed the structural regions that are responsible for monomer-monomer recognition during dimer formation and for protein-protein interaction and that are important for partner recognition. The pseudoazurin structure was compared with other structures of various type 1 copper proteins and these were grouped into families according to similarities in their secondary structure; this may be useful in the annotation of copper proteins in newly sequenced genomes and in the identification of novel copper proteins.

Ramos, S, Almeida RM, Moura JJ, Aureliano M.  2010.  Implications of oxidovanadium(IV) binding to actin, Jun. J Inorg Biochem. 105:777-83., Number 6 AbstractWebsite

Oxidovanadium(IV), a cationic species (VO(2+)) of vanadium(IV), binds to several proteins, including actin. Upon titration with oxidovanadium(IV), approximately 100% quenching of the intrinsic fluorescence of monomeric actin purified from rabbit skeletal muscle (G-actin) was observed, with a V(50) of 131 muM, whereas for the polymerized form of actin (F-actin) 75% of quenching was obtained and a V(50) value of 320 muM. Stern-Volmer plots were used to estimate an oxidovanadium(IV)-actin dissociation constant, with K(d) of 8.2 muM and 64.1 muM VOSO(4), for G-actin and F-actin, respectively. These studies reveal the presence of a high affinity binding site for oxidovanadium(IV) in actin, producing local conformational changes near the tryptophans most accessible to water in the three-dimensional structure of actin. The actin conformational changes, also confirmed by (1)H NMR, are accompanied by changes in G-actin hydrophobic surface, but not in F-actin. The (1)H NMR spectra of G-actin treated with oxidovanadium(IV) clearly indicates changes in the resonances ascribed to methyl group and aliphatic regions as well as to aromatics and peptide-bond amide region. In parallel, it was verified that oxidovanadium(IV) prevents the G-actin polymerization into F-actin. In the 0-200 muM range, VOSO(4) inhibits 40% of the extent of polymerization with an IC(50) of 15.1 muM, whereas 500 muM VOSO(4) totally suppresses actin polymerization. The data strongly suggest that oxidovanadium(IV) binds to actin at specific binding sites preventing actin polymerization. By affecting actin structure and function, oxidovanadium(IV) might be responsible for many cellular effects described for vanadium.

Raimundo, J, Vale C, Canario J, Branco V, Moura I.  2010.  Relations between mercury, methyl-mercury and selenium in tissues of Octopus vulgaris from the Portuguese Coast, Jun. Environmental Pollution. 158:2094-2100., Number 6 AbstractWebsite

Mercury, methyl-mercury (MeHg) and selenium were determined in digestive gland and mantle of Octopus vulgaris, from three areas of the Portuguese coast. To our knowledge these are the first data on MeHg in cephalopods. Concentrations were higher in the digestive gland and percentage of MeHg in mantle. Enhanced Hg and MeHg levels were obtained in digestive gland of specimens from Olhao (3.1-7.4 and 2.0-5.0 mu g g(-1) respectively). Differences between areas may be partially related to Hg availability. Relationships between concentrations in mantle and digestive gland pointed to proportional increases of Hg and MeHg in tissues of specimens from Matosinhos and Cascais, but relatively constant values in mantle of individuals from Olhao (higher contamination). Se:Hg molar ratio in digestive gland was 32 and 30 in octopus from Matosinhos and Cascais, respectively, and 5.4 from Olhao. The proximity to the unit suggests demethylation as response to elevated MeHg levels in digestive gland. (C) 2010 Elsevier Ltd. All rights reserved.

{Vidal Pinheiro}, A, Conde J, Parola {AJ}, Lima {JC}, Baptista {PV}.  2010.  Use of cyclodextrins as scavengers of inhibitory photo-products in light controlled in vitro synthesis of RNA, jun. Journal of Photochemistry and Photobiology A: Chemistry. 213:147–151., Number 2-3: Elsevier Abstract

We recently reported on the use of caged nucleotides to attain full control of enzymatic polymerization of RNA solely by light. In the absence of light no RNA formation was possible due to the efficient caging by the coumarin moiety; after irradiation, caged ATP was released with quantitative precision and RNA polymerization was resumed. As photolabile protecting group [7-(diethylamino) coumarin-4-yl]methyl] (DEACM) was used due to its high absorbance in the visible region of the spectrum, fast deprotection kinetics and absence of radical intermediates. However, the 7-diethylamino-4-hydroxymethylcoumarin photo-product (DEACM-OH) was shown to inhibit the transcription reaction for concentrations higher than 30 μM [5]. This inhibition has been associated with poor water solubility, which is commonly dealt with via cumbersome chemical modifications of the protecting moiety. To overcome inhibition, we evaluated the use of molecular scavengers to sequester DEACM-OH formed after irradiation. Determination of association constants of coumarin with β-cyclodextrins allowed the assessment of its capability to remove free coumarin molecules from solution. The influence of β-cyclodextrin in transcription reaction was also assessed. Results show that β-cyclodextrin can be successfully used as scavenger as it increases the DEACM-OH threshold concentration for inhibition, amplifying the efficiency of light controlled in vitro transcription.

Carmali, S, Alves VD, Coelhoso IM, Ferreira LM, Lourenco AM.  2010.  Recovery of lupanine from Lupinus albus L. leaching waters, JUL 30. SEPARATION AND PURIFICATION TECHNOLOGY. 74:38-43., Number 1 Abstract
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