Nuestros investigadores

Gene therapy with an adeno-associated vector (AAV) serotype 8 encoding the human ATPase copper-transporting beta polypeptide (ATP7B) complementary DNA (cDNA; AAV8¿ATP7B) is able to provide long-term copper metabolism correction in 6-week-old male Wilson disease (WD) mice. However, the size of the genome (5.2 kilobases [kb]) surpasses the optimal packaging capacity of the vector, which resulted in low-yield production; in addition, further analyses in WD female mice and in animals with a more advanced disease revealed reduced therapeutic efficacy, as compared to younger males. To improve efficacy of the treatment, an optimized shorter AAV vector was generated, in which four out of six metal¿binding domains (MBDs) were deleted from the ATP7B coding sequence, giving rise to the miniATP7B protein (delta57-486-ATP7B). In contrast to AAV8-ATP7B, AAV8-miniATP7B could be produced at high titers and was able to restore copper homeostasis in 6- and 12-week-old male and female WD mice. In addition, a recently developed synthetic AAV vector, AAVAnc80, carrying the miniATP7B gene was similarly effective at preventing liver damage, restoring copper homeostasis, and improving survival 1 year after treatment. Transduction of approximately 20% of hepatocytes was sufficient to normalize copper homeostasis, suggesting that corrected hepatocytes are acting as a sink to eliminate excess of copper.

A new range of grouts prepared by air lime and metakaolin (MK) as a pozzolanic admixture has been obtained by using as dispersing agents two polymers, namely poly-naphthalene sulfonate (PNS) and lignosulfonate (LS), with the aim of improving the fluidity of the fresh grouts. Fluidity and setting times of the grouts were assessed. Differences in the molecular architecture and in the anionic charge density explained the different adsorption of the polymers and the different performance. The higher anionic charge of PNS and its linear shape explained its better adsorption and effectiveness. The pozzolanic reaction was favoured in grouts with PNS, achieving the highest values of compressive strength (4.8 MPa after 182 curing days). The addition of PNS on lime grouts slightly decreased the frost resistance of the grouts (from 24 freeze-thaw cycles for the polymer-free samples to 19 or 20 cycles with 0.5 or 1 wt % of PNS). After the magnesium sulphate attack, grouts were altered by decalcification of hydrated phases and by formation of hexahydrite and gypsum. A protective role of portlandite against magnesium sulphate attack was clearly identified. Accordingly, the polymer LS, which preserves a significant amount of Ca(OH)2, could be an alternative for the obtaining of grouts requiring high sulphate attack resistance.

Mortars with two different binders (Portland cement (PC) and high alumina cement (HAC)) were modified upon the bulk incorporation of nano-structured photocatalytic additives (bare TiO2, and TiO2 doped with either iron (Fe-TiO2) or vanadium (V-TiO2)). Plastic and hardened state properties of these mortars were assessed in order to study the influence of these nano-additives. Water demand was increased, slightly by bare TiO2 and Fe-TiO2, and strongly by V-TiO2, in agreement with the reduction of the particle size and the tendency to agglomerate. Isothermal calorimetry showed that hydration of the cementitious matrices was accelerated due to additional nucleation sites offered by the nano-additives. TiO2 and doped TiO2 did not show pozzolanic reactivity in the binding systems. Changes in the pore size distribution, mainly the filler effect of the nano-additives, accounted for the increase in compressive strengths measured for HAC mortars. A complex microstructure was seen in calcium aluminate cement mortars, strongly dependent on the curing conditions. Fe-TiO2 was found to be homogeneously distributed whereas the tendency of V-TiO2 to agglomerate was evidenced by elemental distribution maps. Water absorption capacity was not affected by the nano-additive incorporation in HAC mortars, which is a favourable feature for the application of these mortars.

Our data demonstrate that AAV8-AAT-ATP7B-mediated gene therapy provides long-term correction of copper metabolism in a clinically relevant animal model of WD providing support for future translational studies.

Polynaphtalenesulfonate (PNS) and lignosulfonate (LS) were tested as superplasticizers in pastes and mortars of pure air lime and air lime with a pozzolanic additive, nanosilica (NS). LS showed a better plasticizing effect than PNS: the flowability of the samples with LS as well as the slump retention over time was larger. LS strongly hindered carbonation due to its ability to form Ca2+ complexes. In mortars with NS, PNS was seen to interfere with the C-S-H formation, resulting in lower mechanical strengths. Adsorption isotherms and zeta potential showed that PNS was more adsorbed than LS onto lime and C-S-H particles. PNS acted mainly through electrostatic repulsion owing to its high anionic charge density and flat adsorption. However, LS was more efficient as superplasticizer in air lime media, steric hindrance being the main mechanism responsible for avoiding flocculation. Furthermore, LS yielded high compressive strengths in mortars with NS.

Oxaliplatin (L-OH), a platinum derivative with good tolerability is currently combined with Cetuximab (CTX), a monoclonal antibody (mAb), for the treatment of certain (wild-type KRAS) metastatic colorectal cancer (CRC) expressing epidermal growth factor receptor (EGFR). Improvement of L-OH pharmacokinetics (PK) can be provided by its encapsulation into liposomes, allowing a more selective accumulation and delivery to the tumor. Here, we aim to associate both agents in a novel liposomal targeted therapy by linking CTX to the drug-loaded liposomes. These EGFR-targeted liposomes potentially combine the therapeutic activity and selectivity of CTX with tumor-cell delivery of L-OH in a single therapeutic approach. L-OH liposomes carrying whole CTX or CTX-Fab¿ fragments on their surface were designed and characterized. Their functionality was tested in vitro using four human CRC cell lines, expressing different levels of EGFR to investigate the role of CTX-EGFR interactions in the cellular binding and uptake of the nanocarriers and encapsulated drug. Next, those formulations were evaluated in vivo in a colorectal cancer xenograft model with regard to tumor drug accumulation, toxicity and therapeutic activity. In EGFR-overexpressing cell lines, intracellular drug delivery by targeted liposomes increased with receptor density reaching up to 3-fold higher levels than with non-targeted liposomes. Receptor specific uptake was demonstrated by competition with free CTX, which reduced...

Aflatoxins (AFs) content was analyzed in bovine feedstuff from dairy farms in Spain.¿None of the samples exceeds AFB1 legislation but a high incidence (90%) was found.¿Geographical location, unlike season or feeding system, had limited influence on AFs.¿Organic homemade feedstuff showed non-detected level of AFs throughout the study. Aflatoxins (B1, B2, G1 and G2) are produced by the fungi Aspergillus (A. flavus and A. parasiticus) in substrates used in cattle feed manufacturing. Aflatoxin M1 (AFM1) is a major metabolite of Aflatoxin B1 (AFB1) which may be present in milk from animals that consume contaminated feed. Levels of aflatoxins in 78 dairy cow feedstuff samples from 40 farms located in Navarra were determined by HPLC-FLD (High Performance Liquid Chromatography with fluorescence detection) and post-column derivatization. The influence of geographical location, season and type of feeding system on aflatoxin content was studied. The climatic profile of AFB1 pointed to spring as the season with the highest aflatoxin level (0.086¿g/kg), followed by winter and summer (0.075 and 0.030¿g/kg, respectively), and to a lesser degree, autumn (0.017¿g/kg). Moreover, wet and dry TMR (Total Mixed Ration) feeding systems (i.e. AFB1: 0.076 and 0.068¿g/kg; Aflatoxin G1 (AFG1): 0.050 and 0.011¿g/kg, respectively) showed a greater content of the analyzed aflatoxins in comparison with compound feed (i.e. AFB1: 0.039¿g/kg; AFG1: 0.007¿g/kg). The fact that the majority of the samples collected were based on compound feed shows that this type was preferred by most dairy farmers. The undetectable levels of aflatoxins in the organic homemade compound feedstuff are also worth mentioning. While none of the feedstuff samples contained amounts over those permitted under European legislation (5¿g/kg), the theoretical extrapolation of the carryover rate suggested in previously published experiments of AFB1 to AFM1 in secreted cow's milk predicts that only one of the feed samples studied had a positive aflatoxin level (53.4ng/kg) higher than the legal limit for raw cow's milk.

The performance of air lime mortars modified by the incorporation of large amounts of nanostructured colloidal silica ¿ nanosilica, NS - (6, 10 and 20 wt.% with respect to lime) was the main objective of this work. Fresh mixture properties (water demand, setting time and plastic shrinkage), mechanical strengths up to one year and specimens¿ durability after accelerated ageing conditions (climatic chamber, freeze-thaw cycles and sulfate attack by MgSO4 corrosion test) were evaluated. NS was seen to have a strong pozzolanic activity in air lime media. Although the addition of NS gave rise to an increase in volume contraction, the superficial cracking caused by the drying shrinkage was reduced. A noticeable increase in the compressive strength values was observed in the NS-bearing mortars owing to the NS filler effect and the C-S-H formation, as proved by SEM examination and MIP analysis. A honeycomb-shaped network of C-S-H phases appeared as the prevailing microstructure in mortars with large NS additions. In the face of accelerated ageing processes, the presence of NS made the mortars more durable, delaying the progress of decay.

The oxidative stability of seven oils with different fatty acid profiles was assessed. Oxidation at 0, 2 and 4 h at 180 °C was monitored by measuring the absorbance of thiobarbituric acid reactive substances (TBARS) along the absorption spectrum (300¿600 nm), the volatile aldehydes (HS-SPME¿GC¿MS) and the fatty acid profile (FID-GC). TBARS absorption spectrum behavior depended on the lipid composition of heated oils. Higher absorbance increments during heating were noticed at 390 nm compared to 532 nm (from 2 to 21 fold higher depending on the oil), pointing to its better sensitivity to detect oxidation. Furthermore, a close relationship between ABS390, the loss of polyunsaturated fatty acids and their corresponding oxidation compounds (volatile aldehydes) was revealed by Principal Component Analysis. Multiparametric equations allowed predicting the formation of volatile aldehydes of heated oils by measuring only two parameters: TBARS390 during their heating, and the lipid profile in unheated oils (MUFA, ¿-3 and ¿-6). Results pointed out the interest of choosing ABS390 when the oxidative evolution of vegetable oils under heating is assessed by the TBARS test

Two polycarboxylate ether copolymers were assessed as superplasticizers (SPs) for hydrated lime pastes modified with two reactive compounds, nanosilica (NS) and ceramic metakaolin (MK). Characterization of the molecular structure of the SPs by Size Exclusion Chromatography, XRD, FTIR and MALDI-TOF (Matrix Assisted Laser Desorption Ionization Time-of-Flight) mass spectrometry was performed. The structures of the polymers were seen to be star- and worm-like shapes. A close relationship was found between the molecular architecture and the flowability of the pastes, being the star-shaped plasticizer the most efficient. Zeta potential assessment allowed us to elucidate a steric hindrance as the main action mechanism for these polymers. The large specific surface area of nanosilica led to a large SPs consumption as compared with metakaolin with lower surface area. However, SPs in MK¿lime samples were attached favourably on the C¿S¿H and aluminate hydrates, so that the dispersing action was greater with respect to NS¿lime suspensions.

Topical therapy is the ideal outpatient treatment of cutaneous leishmaniasis (CL) because of the ease of administration and lower cost. It could be suitable as monotherapy for localized cutaneous leishmaniasis (LCL) or in combination with systemic therapies for more severe forms of the disease. Although paromomycin (PM) ointment can be recommended for the treatment of LCL caused by Leishmaniamajor, a more effective topical treatment should be achieved regarding the physicochemical properties of this aminoglucoside and its rather poor intrinsic antileishmanial activity, that hampers the accumulation of enough amount of drug in the dermis (where the infected macrophages home) to exert its activity. In this work, we determined a 50% effective dose of 5.6 ¿M for a novel compound, bis-4-aminophenyldiselenide, against L. major intracellular amastigotes. This compound and PM were formulated in chitosan hydrogels and ex vivo permeation and retention studies in the different skin layers were performed with pig ear skin in Franz diffusion cells. The results showed that less than 2¿4% of the diselenide drug penetrated and permeated through the skin. In contrast, the percentage of PM penetration was about 25¿60% without important retention in the skin. When topically applied to lesions of L. major infected BALB/c mice, the novel diselenide chitosan formulation was unable to slow lesion progression and reduce parasite burden. Considerations during the process of novel drug development and

Polyphosphate-modified calcium aluminate cement matrices were prepared by using aqueous solutions polluted with toxic metals as mixing water to obtain waste-containing solid blocks with improved management and disposal. Synthetically contaminated waters containing either Pb or Cu or Zn were incorporated into phosphoaluminate cement mortars and the effects of the metal¿s presence on setting time and mechanical performance were assessed. Sorption and leaching tests were also executed and both retention and release patterns were investigated. For all three metals, high uptake capacities as well as percentages of retention larger than 99.9% were measured. Both Pb and Cu were seen to be largely compatible with this cementitious matrix, rendering the obtained blocks suitable for landfilling or for building purposes. However, Zn spoilt the compressive strength values because of its reaction with hydrogen phosphate anions, hindering the development of the binding matrix.

BACKGROUND: A combined technological approach was applied in the development of healthier dry fermented sausages: a partial substitution of the pork back fat by pre-emulsified linseed oil and a partial replacement of sodium chloride with calcium ascorbate at two different levels, leading to low amounts of salt (14gSalt and 10gSalt, with 14 g and 10 g NaCl per kg of mixture, respectively). RESULTS: The developed products (14gSalt and 10gSalt) showed adequate results for aw (0.85 and 0.87) and pH (4.98 and 5.21), and low lipid oxidation values (1.4 x 104 and 1.5 x 105 g malondialdehyde (MDA) kg1). The lipid modification led to a significantly higher supply of -3 (23.3 g kg1) compared to the control (3.2 g kg1). Simultaneously, reductions of 38% and 50% in sodium content and a calcium supply of 4 and 5.2 g kg1 were achieved in the 14gSalt and 10gSalt formulations, respectively, compared to the control products (26 g salt and 0.87 g kg1 Ca). Instrumental analysis of colour and texture and sensory studies demonstrated that the organoleptic quality of the new formulations was similar to that of traditional products. CONCLUSIONS: The developed dry fermented sausages showed healthier properties than traditional ones owing to their reduced sodium and higher calcium content and a significant supply of -3 fatty acids. (c) 2012 Society of Chemical Industry

The effect of storage temperature (65 degrees C, 48 h) on the oxidative stability of a food-grade water-in-oil-in-water (W/O/W) emulsion was studied by comparison with an oil-in-water (O/W) emulsion. The emulsions were prepared with linseed oil or olive oil, and in each case, two antioxidants were evaluated, an aqueous Melissa lyophilized extract and BHA. Emulsions were characterized using bright field light microscopy and the oxidation was monitored by measuring the lipid hydroperoxides, thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and trienes (CT), alpha-tocopherol and Lipophilic Oxygen Radical Absorbance Capacity (L-ORACFL) Assay. A great stability of olive oil emulsions was observed, without noticing differences between antioxidants or type of emulsion. This behavior was not observed in linseed oil emulsions. In this case the lipophilic antioxidant (BHA) seemed to be more efficient delaying the lipid oxidation in W/O/W emulsions than the water Melissa extract while the opposite occurs in the O/W emulsion. The type of antioxidant is a key factor in controlling oxidation in W/O/W and O/W emulsions which are prepared with highly polyunsaturated oils, but not in the case of highly monounsaturated ones.

Tyrosol and caffeic acid are biophenols that contribute to the beneficial properties of virgin olive oil. The influence of hydroxypropyl-beta-cyclodextrin (HP beta-CD) on their respective antioxidant capacities was analyzed. The ORAC antioxidant activity of tyrosol (expressed as mu M Trolox equivalents/mu M Tyrosol) was 0.83 +/- 0.03 and it increased up to 1.20 +/- 0.11 in the presence of 0.8 mM HP beta-CD. However, the ORAC antioxidant activity of caffeic acid experienced no change. The different effect of HP beta-CD on each compound was discussed. In addition, the effect of increasing concentrations of different cyclodextrins in the development of ORAC-fluorescence (ORAC-FL) assays was studied. The ORAC signal was higher for HP beta-CD, followed by M beta-CD, beta-CD, gamma-CD and finally alpha-CD. These results could be explained by the formation of inclusion complexes with fluorescein.

The ability of calcium aluminate cement (CAC) to encapsulate toxic metals (Pb, Zn and Cu) was assessed under two curing conditions. Changes in the consistency and in the setting time were found upon the addition of the nitrates of the target metals. Both Pb and Cu caused a delay in CAC hydration, while Zn accelerated the stiffening of the mortar. Compressive strengths of the metal-doped mortars, when initially cured at 60ºC / 100%RH, were comparable with that of the free-metal mortar. Three different pore size distribution patterns were identified and related to the compounds identified by XRD and SEM. Sorbent capacities of CAC for the toxic metals were excellent: a total uptake was achieved for up to 3 wt.% loading of the three metals. In this way, CAC mortars were perfectly able to encapsulate the toxic metals, allowing the use of CAC for waste management as proved by the leaching tests.

A pre-emulsified mixture of linseed and algae oils (15/10) and stabilized with 686 ppm of a lyophilized water extract of Melissa officinalis, was successfully applied in dry fermented sausages to increase the ¿-3 PUFA content. The objective of this work was to evaluate the stability of this modified formulation during the storage and to compare it to that of a traditional formulation. Traditional and modified products were stored during 90 days at 4 ºC in aerobic conditions. Fatty acid profiles, TBARS and volatile compounds derived from oxidation were analyzed at 0, 30 and 90 days of storage. The fatty acid profiles did not significantly change along the storage period. The stabilizing effect of the natural antioxidants of M. officinalis could contribute to detect no losses of ¿-3 PUFA in Modified (30 days: 2.13 g/100 g of product, 90 days: 2.33 g/100 g of product), whereas in Control products a slightly significant reduction was detected (30 days: 0.34 g/100 g of product, 90 days: 0.29 g/100 g of product). After 90 days, the increases of TBARS and hexanal content were much higher in Control than in Modified (Control: 1.41 mg MDA/kg & 17,915 ng dodecane/kg of dry matter; Modified: 0.48 mg MDA/kg & 2,496 ng dodecane/kg of dry matter). In conclusion, the lyophilized water extract of M. officinalis protected high ¿-3 PUFA of dry fermented sausages from oxidation along the storage time, guaranteeing the nutritional improvements achieved with the modified formulation.

In this work, the Film Method (FM), Reverse-Phase Evaporation (REV), and the Heating Method (HM) were applied to prepare PEG-coated liposomes of oxaliplatin with natural neutral and cationic lipids, respectively. The formulations developed with the three methods, showed similar physicochemical characteristics, except in the loading of oxaliplatin, which was statistically lower (P < 0.05) using the HM. The incorporation of a semi-synthetic lipid in the formulation developed by FM, provided liposomes with a particle size of 115 nm associated with the lowest polydispersity index and the highest drug loading, 35%, compared with the other two lipids, suggesting aft increase in the membrane stability. That stability was also evaluated according to the presence of cholesterol, the impact of the temperature, and the application of different cryoprotectants during the lyophilization. The results indicated long-term stability of the developed formulation, because after its intravenous in vivo administration to HT-29 tumor bearing mice was able to induce an inhibition of tumor growth statistically higher (P < 0.05) than the inhibition caused by the free drug. In conclusion, the FM was the simplest method in comparison with REV and HM to develop in vivo stable and efficient PEG-coated liposomes of oxaliplatin with a loading higher than those reported for REV. (C) 2012 Elsevier B.V. All rights reserved.

The incidence of aflatoxin M-1 (AFM(1)) in 69 different infant formulae marketed in Spain between 2007 and 2008 was studied and dietary intake estimated. Samples were analysed using an HPLC method coupled with fluorescence detection after immunoaffinity column clean-up. The toxin was detected in 26 formulae (37.7%) at levels below the permissible limit set by EC legislation, giving a range of 0.6-11.6 ng kg(-1) with a mean value of 3.1 ng kg(-1). Increasing occurrence was found in those formulae produced by the less complex manufacturing processes affecting casein/whey protein ratio: pre-term, 14.3%; starter, 35.3%; follow-up, 42.1%; toddler 87.6%; while hypoallergenic and lactose-free were totally exempt. Additionally, the influence of main protein source and physical state (powdered and ready-to-use formula) on AFM(1) occurrence was evaluated leading to similar conclusions. Dietary AFM1 weekly intake was observed to be stable around 1 ng kg(-1) bw for standard formula and 0.1 ng kg(-1) bw for pre-term feeding.

Biodegradable poly (lactic-co-glycolic) acid (PLGA) nanoparticles incorporating cisplatin have been developed to evaluate its in vivo efficacy in tumor-bearing mice. In vitro Study proved two mechanisms of action for cisplatin depending on the dose and the rate at which this dose is delivered. In vivo study, 5 mg/kg of cisplatin nanoparticles administered to mice, exhibited a tumour inhibition similar to free cisplatin, although the area under cisplatin concentration-time Curve between 0 and 21 days (AUC(0-21)) had lower Value for the formulation than for drug solution (P < 0.05). This result was associated with a higher activation of apoptosis in tumor, mediated by caspase-3, after nanoparticles administration. Toxicity measured as the change in body weight, and blood urea nitrogen (BUN) plasma levels showed that cisplatin nanoparticles treatment did not induce significant changes in both parameters compared to control, while for free drug, a statistical (P < 0.01) increase was observed. In addition, a good correlation was found between time profiles of tumor volume and vascular endothelial growth factor (VEGF) plasma levels, suggesting that its expression could help to follow the efficacy of the treatment. Therefore, the PLGA nanoparticles seem to provide a promising carrier for cisplatin administration avoiding its side effects without a reduction of the efficacy, which was consistent with a higher activation of apoptosis than free drug.

Aflatoxins (AFB1, AFB2, AFG1 and AFG2) are immunosuppressant, mutagenic, teratogenic and carcinogenic agents with a widespread presence in foodstuffs. Since human exposure to aflatoxins occurs primarily by contaminated food intake, and given the greater susceptibility of infants to their adverse effects, the quantification of these mycotoxins in infant food based on cereals is of relevance. Aflatoxin levels were determined in 91 Spanish infant cereals classified in terms of non- and organically produced and several types from 10 different manufacturers, using a extraction procedure followed by inmunoaffinity column clean-up step and HPLC with fluorescence detection (FLD) and post-column derivatisation (Kobra Cell system). Daily aflatoxin intake was also assessed. Preliminary analysis showed a valuable incidence of detected infant cereal samples at an upper concentration level than the detection limit for total aflatoxin (66%), corresponding to a 46, 40, 34 and 11% for AFB1, AFB2, AFG1 and AFG2, respectively. Lower aflatoxin values (median, Q1, Q3) in conventional infant cereal (n = 74, AFB1: LOD (n.d.; 0.02), AFB2: n.d. (n.d.; 0.01), AFG1: LOD (n.d.; 0.004), and AFG2: n.d. (n.d.; LOD) and total AF (AFtotal): 0.01 (LOD; 0.04 mu g kg-1) in comparison with infant cereal ecologically produced (n = 17, AFB1: 0.02 (0.02; 0.21), AFB2: n.d. (n.d.; 0.03), AFG1: 0.02 (0.01; 0.05), and AFG2: 0.007 (n.d.; 0.02) and AFtotal: 0.05 (0.03; 0.31 mu g kg-1) were found. In addition, five organic formulations (3.11, 1.98, 0.94, 0.47 and 0.21 mu g kg-1) exceeded European AFB1 legislation (0.10 mu g kg-1) versus two conventional cereals (0.35 and 0.12 mu g kg-1). According to the type of infant cereal, those with cocoa had the highest aflatoxin levels. Gluten-free and cereals with dehydrated fruits had an intermediate level and milk- or honey-based cereals and multi-cereals contained the lowest levels. With the exception of the non-compliant cocoa-based organic formulation, none of the infant cereals analyzed gave a higher intake of 1 ng kg-1 body weight per day, suggesting that infants fed on infant cereals are exposed to a low health hazard. Nevertheless, manufacturers are advised for continued efforts in routine monitoring and a more careful selection of raw material to minimize aflatoxin levels in these infant foods.

This work reports the obtaining of lime-based grouts as repairing materials. Microsilica was added as pozzolanic additive to enhance the compressive strength of the hardened grouts. Sodium oleate, as water repellent admixture, and different superplasticizers (SPs) were also incorporated to reduce the water absorption and to enhance the injectability of the grouts. Polycarboxylate ether (PCE), polynaphthalene sulfonate (PNS), melamine sulfonate (MMS) and polyacrylic acid (PA) were tested as SPs. Regarding the fluidity of the grouts, PCE was seen to improve the injectability, followed by PNS, MMS and PA. However, PCE addition was also accompanied by a severe delay in the setting time. The other three superplasticizers did not provoke significant delays in the hardening of the samples. The water contact angle underwent an increase pointing to an effective hydrophobization of the surface as a consequence of the water repellent admixture. The combination with PCE was the most effective in keeping the water repellency in comparison with the control sample (lime grout + oleate). MMS yielded high compressive strengths and durability of the mortars, in the face of freezing-thawing cycles, was enhanced.

Diferentes morteros de cal fueron modificados por la incorporación en masa de aditivos fotocatalíticosnanoestructurados (TiO2 o TiO2 dopado con hierro (Fe-TiO2) o vanadio (V-TiO2)). Las propiedades plásticas y endurecidas de estos morteros han sido evaluadas para estudiar la influencia de estos nanoaditivos. Los retrasos en la demanda de agua observados en las pastas de cal se atribuyeron al impedimento de la difusión de CO2 dentro de la pasta. El TiO2 y el TiO2 dopado no mostraron reactividad puzolánica alguna. El examen por microscopía electrónica de barrido de los morteros de cal mostró que las fases predominantes en la microestructura eran placas hexagonales de portlandita y las aglomeraciones gruesas escalenoédricas de calcita. Se encontró que el Fe-TiO2 se distribuía homogéneamente, mientras que el análisis EDS demostró la tendencia al aglomeramiento del V-TiO2. La capacidad de absorción de agua no se vio afectada por la incorporación de nanoaditivos, lo cual es una característica favorable para la aplicación de estos morteros.

Los morteros de relleno o inyección, especialmente destinados a reparación de cavidades y defectos de albañilería, deben fluir adecuadamente en estado fresco y combinar resistencia y durabilidad. Para conseguir algunas de estas características pueden utilizarse aditivos químicos: superplastificantes, para mejorar la fluidez; adiciones puzolánicas, para conseguir resistencias adecuadas en ambientes con limitado acceso de CO2 y una mejora de la durabilidad; e hidrofugantes, de manera que, sin perjudicar la permeabilidad de estos materiales al vapor de agua, se evite la penetración de agua por capilaridad mejorando la durabilidad. Sin embargo, en la mayor parte de los casos, toda la información disponible se circunscribe al efecto de un único aditivo, sin contemplar el posible efecto conjunto o incluso sinérgico de las combinaciones más interesantes de dos o más aditivos y/o adiciones puzolánicas. El estudio de las sinergias entre estos componentes ofrece posibilidades muy interesantes de avance científico-técnico. Precisamente este es el objetivo del trabajo: diseño de nuevos morteros de inyección de cal que puedan ser utilizados para la restauración del Patrimonio Edificado mediante combinación adecuada de aditivos superplastificantes (éteres de policarboxilato, condensados de naftaleno-formaldehído, sulfonato de melamina y ácido poliacrílico), hidrofugante (oleato sódico) y adiciones minerales puzolánicas (microsílice y metacaolín).

This contribution dealt with the design of different air lime mortars and pastes by combining a nanostructured pozzolanic additive, nanosilica, and different dispersing agents, superplasticizers (two different polycarboxylate ethers (PCE), a polynaphthalene sulfonate-based polymer (PNS) and a lignosulfonate (LS)). In pure air lime systems, the highest effectiveness was shown by the PCE1, whereas the PNS was the less effective superplasticizer. In samples with nanosilica, the PCE1 was also the most effective superplasticizer. LS was seen to be effective at low dosages. In the presence of the pozzolanic additive, there was a high consumption of polycarboxylates. Nanosilica provided no ¿active¿ adsorption sites, resulting in a slight decrease of the zeta potential values. PCE1 showed low adsorbed amounts, better dispersing action and required lower dosage of plasticizing agent. There was a positive combination between lime mortars with nanosilica and polycarboxylates, which resulted in a mechanical strength improvement. Also the combined presence of nanosilica, for example, with PNS or with LS yielded better compressive strengths, being LS more effective than PNS: SEM images showed the better formation of C-S-H phases in LS-mortars.

A superplasticizing admixture of natural origin, lignosulfonate (LS), was incorporated to air lime mortars sometimes modified with a pozzolanic additive, metakaolin, to obtain a new range of repair mortars to be applied in Built Heritage. LS improved the flowability of the air lime samples and showed good slump retention over time: for example, after 150 minutes of the air lime pastes preparation, blends with LS lost only ca. 13% of the slump value. Experimental results showed that LS interfered with the carbonation due to its ability to form Ca2+ complexes. Adsorption isotherms and zeta potential measurements showed that LS was scarcely adsorbed onto lime and C-S-H particles. Due to its branchy structure, LS exhibited an adsorption mechanism leading to steric hindrance as the main responsible mechanism for avoiding flocculation. The presence of free LS molecules in the dispersion was seen to improve the plasticizing effect of this polymer. Flexural and compressive strengths as well as the durability in the face of freezing-thawing cycles of these mortars were also determined to assess the applicability of these repair mortars.

Although CAC is used in many building as well as industrial structures, its modification upon addition of photocatalytic additives has not yet been addressed and that is precisely the purpose of the present work. We intend to obtain for the first time depolluting CAC mortars modified with different amounts of TiO2. The effect of the TiO2 incorporation on setting time, compressive strength and mineralogical composition of the CAC mortars will be assessed. PCO efficiency of these TiO2-bearing CAC mortars will be also measured by means of the NOx abatement. The modified depolluting mortars could be then applied in different tunnels, industrial floors and urban areas in which CACs are usually applied.

The rationale is that polyphosphate-CAC matrices have shown interesting potential to solidify/stabilize heavy metals, owing to the aforementioned acid-base reaction that yields a compact and low porous matrix mainly composed of ACP - amorphous calcium phosphate -, which can be able to retain hazardous compounds. We aimed to take advantage of the reactivity of one of the sludge components: the sludges with relatively large concentrations of phosphate are expected to act themselves as reactants that, interacting with the CAC, could result in a very effective retaining system of the sludge constituents. Sludge samples from two locations have been incorporated in high proportion within the mix. We discussed the effects of the sludge on the CAC mortar and a possible interaction mechanism is provided.

This book collects the abstracts of the communications presented in the 5th Historic Mortars Conference (HMC 2019) organized by the Heritage, Materials & Environment (MIMED) Research Group of the Chemistry Department of the University of Navarra at the School of Sciences in Pamplona from 19 to 21 June 2019.