Hydrothermal Transformation of Eggshell Calcium Carbonate into Apatite Micro-Nanoparticles: Cytocompatibility and Osteoinductive Properties

This research was funded by Spanish Agencia Estatal de Investigación of the Ministerio de Ciencia e Innovación y Universidades (MCIU), Bioscaffold project, ref. PGC2018-102047-B-I00 (MCIU/AEI/FEDER, UE). The Ministry of Science, Technology, and Innovation of Colombia provided support for A.T-M´s participation. P.Á.-L. acknowledge support from MCIN project PCI2019–111931-2 and the European Regional Development Fund–ERDF)—Next Generation/EU program. J.G.-M. acknowledges PCI2020-112108 funded by MCI/AEI/10.13039/501100011033 (Spain) and the European Union “NextGeneration/PRTR”. PCI2020-112108 is part of the CASEAWA project of the ERA-NET Cofund BlueBio Programme, supported by the European Union (H2020). The authors acknowledge the staff of Scientific Instrumentation Centre (CIC) of the University of Granada for HRSEM and TGA characterizations and Scientific and Technical Services of the University of Oviedo for XRD analyses.Supplementary Materials: The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/nano13162299/s1The eggshell is a biomineral consisting of CaCO3 in the form of calcite phase and a pervading organic matrix (1-3.5 wt.%). Transforming eggshell calcite particles into calcium phosphate (apatite) micro-nanoparticles opens the door to repurposing the eggshell waste as materials with potential biomedical applications, fulfilling the principles of the circular economy. Previous methods to obtain these particles consisted mainly of two steps, the first one involving the calcination of the eggshell. In this research, direct transformation by a one-pot hydrothermal method ranging from 100-200 C-circle was studied, using suspensions with a stoichiometric P/CaCO3 ratio, K2HPO4 as P reagent, and eggshells particles (phi < 50 mu m) both untreated and treated with NaClO to remove surface organic matter. In the untreated group, the complete conversion was achieved at 160 C-circle, and most particles displayed a hexagonal plate morphology, eventually with a central hole. In the treated group, this replacement occurred at 180 C-circle, yielding granular (spherulitic) apatite nanoparticles. The eggshell particles and apatite micro-nanoparticles were cytocompatible when incubated with MG-63 human osteosarcoma cells and m17.ASC murine mesenchymal stem cells and promoted the osteogenic differentiation of m17.ASC cells. The study results are useful for designing and fabricating biocompatible microstructured materials with osteoinductive properties for applications in bone tissue engineering and dentistry.Spanish Agencia Estatal de Investigación of the Ministerio de Ciencia e Innovación y Universidades (MCIU)Bioscaffold project PGC2018-102047-B-I00 (MCIU/AEI/FEDER, UE)Ministry of Science, Technology, and Innovation of ColombiaMCIN project PCI2019–111931-2European Regional Development Fund–ERDF—Next Generation/EU programMCI/AEI/10.13039/501100011033 (Spain) PCI2020-112108European Union “NextGeneration/PRTR”European Union (H2020), CASEAWA of ERA-NET, PCI2020-112108University of Granada, Scientific Instrumentation Centre (CIC)University of Oviedo, Scientific and Technical Service

Bioinspired Mineralization of Type I Collagen Fibrils with Apatite in Presence of Citrate and Europium Ions

Synthetic nanostructured hybrid composites based on collagen and nanocrystalline apatites are interesting materials for the generation of scaffolds for bone tissue engineering. In this work, mineralized collagen fibrils were prepared in the presence of citrate and Eu3+. Citrate is an indispensable and essential structural/functional component of bone. Eu3+ endows the mineralized fibrils of the necessary luminescent features to be potentially employed as a diagnostic tool in biomedical applications. The assembly and mineralization of collagen were performed by the neutralization method, which consists in adding dropwise a Ca(OH)2 solution to a H3PO4 solution containing the dispersed type I collagen until neutralization. In the absence of citrate, the resultant collagen fibrils were mineralized with nanocrystalline apatites. When citrate was added in the titrant solution in a Citrate/Ca molar ratio of 2 or 1, it acted as an inhibitor of the transformation of amorphous calcium phosphate (ACP) to nanocrystalline apatite. The addition of Eu3+ and citrate in the same titrant solution lead to the formation of Eu3+–doped citrate–coated ACP/collagen fibrils. Interestingly, the relative luminescent intensity and luminescence lifetime of this latter composite were superior to those of Eu3+–doped apatite/collagen prepared in absence of citrate. The cytocompatibility tests, evaluated by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) colorimetric assay in a dose–dependent manner on GTL–16 human gastric carcinoma cells, on MG–63 human osteosarcoma cells and on the m17.ASC, a spontaneously immortalized mouse mesenchymal stem cell clone from subcutaneous adipose tissue, show that, in general, all samples are highly cytocompatible.This research was funded by Spanish MINEICO and co–funded by FEDER (grant number MAT2014–60533–R). C. V.–E. acknowledges the Spanish MINEICO for his contract PTA2015–11103–I. M.I. acknowledges support by the Italian National Research Program–National Research Council (PNRCNR) Aging Program 2012–2014. The Excellence Network of Crystallography and Crystallization “Factoría de Cristalización” FIS2015–71928–REDC funded by Spanish MINEICO is also acknowledged

Bioinspired crystallization, sensitized luminescence and cytocompatibility of citrate-functionalized Ca-substituted europium phosphate monohydrate nanophosphors

Bio compatible nanosystems exhibiting long lifetime ( ~millisecond) luminescence features are particu l arly relevant in the field of bioimaging. In this study, citrate functionalized calcium doped europium phosphates nanophosphors of the rhabdophane type were prepared at different synthesis times by a bioinspired crystallization route, consisting in thermal decomplexing of ca2•tEu3• {citrate{phosphate{car bonate solutions. The general formula of this material is Ca«Eu1 a(PO4) 1 a(HP04 l,,•nH2O, with CJ. ranging from 0 to 0.58 and n ~ 1. A thorough characterization of the nanoparticles has been carried out by XRD (including data processing with Topas 6.0), HR TEM, TEM, FTIR, TG{ITTA. ICP, dynamic light scattering (OLS), electrophoretic mobility, and fluorescence spectroscopy. Based on these results a crystallization mechanism involving the filling of cationic sites with Ca21ons associated to a concomitant adjustment of the P04{HPO4 ratio was proposed Upon calcium doping, the aspect ratio of the nanoparticles as well as of the crystalline domains decreased and the relative luminescence intensity (R.LI.) could be modulated. Neither the pH nor the ionic strength, nor the temperature (from 25 to 37 C) affected signif icantly the R.L.I. of particles after resuspension in water, leading to rather steady luminescence features usable in a large domain of conditions. This new class of luminescent compounds has been proved to be fully cytocompatible relative to GTL 16 human carcinoma cells and showed an improved cytocompatibil ity as the Ca2+ content increased when contacted with the more sensitive m17. ASC murine mesenchymal stem cells. These biocompatible nanoparticles thus appear as promising new tailorable tools for biomed ical applications as luminescent nanoprobes.We greatly acknowledge the project Biomin nanoapatite MAT2014 60533 R supported by Spanish MINEICO and co funded by FEDER and the Excellence Network of Crystallography and Crystallization "Factoría de Cristalización" FIS2015 71928 REDC supported by Spanish MINEICO. Cristóbal Verdugo Escamilla also acknowledges the Spanish MINEICO for his contract PT A2015 11103 I

Applications of bioclimatology to assess effects of climate change on viticultural suitability in the DO León (Spain)

[EN] Spain accounts for 13.1% of the world’s vineyard area, and viticulture is crucial for the socioeconomic and cultural sectors. Vineyards are among the perennial crops that can suffer most negative impacts under climate change which can pose challenges to the sustainability of viticulture. Local and regional studies are needed to assess these impacts to help implement effective strategies in response to climate change. To this end, our approach involves integrating both conventional agroclimatic indices and those new bioclimatic indices that have proven to be essential for the characterization and demarcation of vineyards into species distribution models to assess areas suitable for viticulture under climate change projections. The proposed methodology was tested in a viticultural region located in northwestern Spain (DO León). An ensemble platform was used to build consensus models encompassing three general circulation models, two emission scenario pathways and two time horizons. Only the predictors that effectively characterize each grape variety were included in the models. The results revealed increases in the continentality index, compensated thermicity index, hydrothermic index of Branas, and temperature range during ripening in all the future scenarios analyzed in comparison to current conditions. Conversely, the values for the annual ombrothermic index and growing season precipitation may decrease in the future. The pattern of changes for 2070 will be more pronounced than for 2050. A significant loss of future habitat suitability was detected within the limits of the study area for the grape varieties analyzed. This negative impact could be counteracted to some degree with new and favorable areas for the cultivation of vineyards in territories located at the north of the DO limits. We suggest that our results could help policymakers to develop practices and strategies to conserve existing grape varieties and to implement efficient adaptation measures for mitigating or anticipating the effects of climate change on viticulture.SIThis work was supported by the Regional Ministry of Education, Junta de Castilla y León (Spain), EDU/667/201

Luminescent biomimetic citrate-coated europium-doped carbonated apatite nanoparticles for use in bioimaging: physico-chemistry and cytocompatibility

Nanomedicine covers the application of nanotechnologies in medicine. Of particular interest is the setup of highly-cytocompatible nanoparticles for use as drug carriers and/or for medical imaging. In this context, luminescent nanoparticles are appealing nanodevices with great potential for imaging of tumor or other targetable cells, and several strategies are under investigation. Biomimetic apatite nanoparticles represent candidates of choice in nanomedicine due to their high intrinsic biocompatibility and to the highly accommodative properties of the apatite structure, allowing many ionic substitutions. In this work, the preparation of biomimetic (bone-like) citrate-coated carbonated apatite nanoparticles doped with europium ions is explored using the citrate-based thermal decomplexing approach. The technique allows the preparation of the single apatitic phase with nanosized dimensions only at Eu3+ doping concentrations ≤0.01 M at some timepoints. The presence of the citrate coating on the particle surface (as found in bone nanoapatites) and Eu3+ substituting Ca2+ is beneficial for the preparation of stable suspensions at physiological pH, as witnessed by the ζ-potential versus pH characterizations. The sensitized luminescence features of the solid particles, as a function of the Eu3+ doping concentrations and the maturation times, have been thoroughly investigated, while those of particles in suspensions have been investigated at different pHs, ionic strengths and temperatures. Their cytocompatibility is illustrated in vitro on two selected cell types, the GTL-16 human carcinoma cells and the m17.ASC murine mesenchymal stem cells. This contribution shows the potentiality of the thermal decomplexing method for the setup of luminescent biomimetic apatite nanoprobes with controlled features for use in bioimaging

Checklist of the vascular plants of the Cantabrian Mountains

We present the first standardized list of the vascular flora of the Cantabrian Mountains, a transitional zone between the Eurosiberian and Mediterranean biogeographic regions in northwestern Spain. The study area comprises 15000 km2 divided in UTM grid cells of 10 km x 10 km, for which we revised occurrence data reported in the Spanish Plant Information System (Anthos) and the online database of Iberian and Macaronesian Vegetation (SIVIM). We used a semi-automatic procedure to standardize taxonomic concepts into a single list of names, which was further updated by expert-based revision with the support of national and regional literature. In the current version, the checklist of the Cantabrian Mountains contains 2338 native species and subspecies, from which 56 are endemic to the study area. The nomenclature of the checklist follows Euro+Med in 97% of taxa, including annotations when other criteria has been used and for taxa with uncertain status. We also provide a list of 492 non-native taxa that were erroneously reported in the study area, a list of local apomictic taxa, a phylogenetic tree linked to The Plant List, a standardized calculation of Ellenberg Ecological Indicator Values for 80% of the flora, and information about life forms, IUCN threat categories and legal protection status. Our review demonstrates how the Cantabrian mountains represent a key floristic region in southern Europe and a relevant phytogeographical hub in south-western Europe. The checklist and all related information are freely accessible in a digital repository for further uses in basic and applied researchThis research was supported by the Jardín Botánico Atlántico de Gijón (SV-20-GIJON-JBA) and SEEDALP project (Spanish Reearch Agency; PID2019-108636GA/AEI/10.13039/501100011033)Peer reviewe

III Jornadas de Jóvenes Investigadores en Arqueología: Libro de Actas

Libro de Actas de las III Jornadas de Jóvenes Investigadores en Arqueologí

Gels for protein crystallization

7th International School on Biological Crystallization (ISBC2019), in Granada (Spain), May 26th to 31st, 201

Crystallization, Luminescence and Cytocompatibility of Hexagonal Calcium Doped Terbium Phosphate Hydrate Nanoparticles

Luminescent lanthanide-containing biocompatible nanosystems represent promising candidates as nanoplatforms for bioimaging applications. Herein, citrate-functionalized calcium-doped terbium phosphate hydrate nanophosphors of the rhabdophane type were prepared at different synthesis times and different Ca2+/Tb3+ ratios by a bioinspired crystallization method consisting of thermal decomplexing of Ca2+/Tb3+/citrate/phosphate/carbonate solutions. Nanoparticles were characterized by XRD, TEM, SEM, HR-TEM, FTIR, Raman, Thermogravimetry, inductively coupled plasma spectroscopy, thermoanalysis, dynamic light scattering, electrophoretic mobility, and fluorescence spectroscopy. They displayed ill-defined isometric morphologies with sizes 50 nm, hydration number n ~ 0.9, tailored Ca2+ content (0.42–8.11 wt%), and long luminescent lifetimes (800–2600 s). Their relative luminescence intensities in solid state are neither affected by Ca2+, citrate content, nor by maturation time for Ca2+ doping concentration in solution below 0.07 M Ca2+. Only at this doping concentration does the maturation time strongly affect this property, decreasing it. In aqueous suspensions, neither pH nor ionic strength nor temperature affect their luminescence properties. All the nanoparticles displayed high cytocompatibility on two human carcinoma cell lines and cell viability correlated positively with the amount of doping Ca2+. Thus, these nanocrystals represent promising new luminescent nanoprobes for potential biomedical applications and, if coupled with targeting and therapeutic moieties, they could be effective tools for theranostics.Spanish Agencia Estatal de Investigación of the Ministerio de Ciencia, Innovación y Universidades (MICIU)European Commission PGC2018102047-B-I00Spanish Ministerio de Economía y Competitividad CTQ2017-88079-

Production of cross-linked lipase crystals at a preparative scale

[EN] The autoimmobilization of enzymes via cross-linked enzyme crystals (CLECs) has regained interest in recent years, boosted by the extensive knowledge gained in protein crystallization, the decrease of cost and laboriousness of the process, and the development of potential applications. In this work, we present the crystallization and preparative-scale production of reinforced cross-linked lipase crystals (RCLLCs) using a commercial detergent additive as a raw material. Bulk crystallization was carried out in 500 mL of agarose media using the batch technique. Agarose facilitates the homogeneous production of crystals, their cross-linking treatment, and their extraction. RCLLCs were active in an aqueous solution and in hexane, as shown by the hydrolysis of p-nitrophenol butyrate and α-methylbenzyl acetate, respectively. RCLLCs presented both high thermal and robust operational stability, allowing the preparation of a packed-bed chromatographic column to work in a continuous flow. Finally, we determined the three-dimensional (3D) models of this commercial lipase crystallized with and without phosphate at 2.0 and 1.7 Å resolutions, respectively.The work was supported by the project BIO2016-74875-P (MINECO), Spain, co-funded by the Fondo Europeo de Desarrollo Regional (FEDER funds), European Union. The authors are grateful to the Spanish Radiation Synchrotron source (ALBA), Barcelona, Spain, and the European Synchrotron Radiation Facility (ESRF), Grenoble, France, for the provision of time and the staff at XALOC (Alba) and ID30B and ID30A-3 (ESRF) beamlines for assistance during data collection.Peer reviewe