Purificación Sánchez-Sánchez

• University of Granada

International and American Associations for Dental, Oral, and Craniofacial Research (IADR)

A novel material with dual activity toward organophosphate (OP) poisoning, based on Zr-MOF-808 and neutral oxime RS69N, has been prepared. The hybrid material has a significant drug payload (5.2 ± 0.9 oxime to MOF-808 molar ratio) and shows a sustained oxime release in simulated physiological media, leading to the successful reactivation of OP-inhi...

A series of Ni(II), Zn(II) and Cd(II) complexes with the Schiff base derived from the condensation 1:1 from pyridine-2-carboxaldehyde and 5,6-diamino-1,3-dimethyluracil (6-amino-1,3-dimethyl-5-[(pyridin-2-ylmethylidene)-amino]pyrimidine-2,4(1H,3H)-dione, DAAUPic) were synthesized and subsequently characterized by means of elemental analysis, FT-IR,...

The aim of the study is to determine the influence of the type of bracket, on bond strength, microhardness and conversion degree (CD) of four resin orthodontic cements. Micro-tensile bond strength (µTBS) test between the bracket base and the cement was carried out on glass-hour-shaped specimens (n=20). Vickers Hardness Number (VHN) and micro-Raman...

We have developed a simple process to fabricate on a bioplatform patterns of nanoparticles of a molecule-based magnet. Nanoparticles of the ferromagnetic Prussian blue derivative CsxNi[Cr(CN)6] were orderly deposited onto S-layers of Lysinibacillus sphaericus, forming a dense carpet of nanoparticles following the square lattice (p4) pattern of the...

A combination of atomic absorption spectroscopy (AAS), Fourier transform infrared spectroscopy (FTIR), scanning electronic microscopy (SEM), and gas adsorption techniques was used to characterize the effect of 30 % hydrogen peroxide (HP) on enamel surface. To perform the analyses of AAS, 1 ml of 30 % HP was added to 30 mg of a bovine enamel powder...

Purpose: The purpose of this study was to test the hypothesis that the pulp medication ferric sulphate (FS) may remain on primary dentin, affecting its microchemical structure and the bond strength of adhesives to primary dentin. Materials and methods: The effects of FS and pre-bonding conditioning (37% phosphoric acid [PA] for 15 s or a self-et...

Purpose: To compare the percentage of collagen exposed in dentin root thirds after two irrigation protocols with manual or rotary instrumentation using two methacrylate resin-based sealers. Materials and methods: Forty-eight single-root human teeth were prepared with manual (n = 24) or nickeltitanium ProFile rotary (n = 24) instrumentation, usin...

To follow the chemical composition of bovine enamel during phosphoric acid-induced demineralization. Enamel samples were ground into a fine powder, selecting the 150- and 200-µm fractions in order to obtain a more homogeneous study material. They were immersed in diluted phosphoric acid (0.1%) for increasing durations ranging from 1 to 1440 min. Th...

To measure the demineralization capacity of 37% phosphoric acid on surface and subsurface bovine enamel after bleaching with hydrogen peroxide (H2O2). Three equally-sized sections with 16 mm2 of exposed enamel surface were obtained from the enamel of 10 bovine incisors. One specimen sample from each crown was assigned to one of three groups (n = 10...

To measure the demineralization capacity of 37% phosphoric acid and shear bond strength (SBS) of brackets attached on bovine enamel at different times after bleaching with 30% hydrogen peroxide. Four equally-sized pieces of each crown from 18 bovine incisors were randomly distributed among 7 groups (n = 10). After bleaching with 30% hydrogen peroxi...

We have covalently coupled fluorophore 4-(2-hydroxyethoxy)-7-nitro-2,1,3-benzoxadiazole (NBD) to the external ferritin shell through lysine residues. An increase in the luminescence quantum yield of the fluorescent ferritin particles and a blue shift in its emission peak compared to individual fluorophore were obsd. The study of the particles by tr...

We have prepared water-soluble gadolinium oxide nanoparticles that show potential as MRI contrast agents. The particles were built into the apoferritin cavity and have an average size of 5 nm. After seven days a loss of 5% of Gd was detected compared with the as-prepared samples; after that the Gd remained constant and stabilized inside the apoferr...

Objectives: We have investigated in detail the evolution of the chemical composition of bovine enamel during phosphoric acid induced demineralization. Materials and Methods: We used for this study powdered bovine enamel as starting material in order to have a more reactive and homogeneous material. We immersed the enamel samples in diluted ph...

Metal (Cu, Co, Ni and Ag) nanoparticles have been prepared within the apoferritin cavity using M(II)-loaded apoferritin as a chemically and spatially confined environment for their construction. The protein shell prevents bulk aggregation of the metal particles,, rendering them water soluble. Optical Ag and Cu nanoparticles showed characteristic su...

Transmission Electron Microscopy (TEM), X-ray Absorption Near Edge Spectroscopy (XANES), Electron Energy-Loss Spectroscopy (EELS), Small-Angle X-ray Scattering (SAXS), and SQUID magnetic studies were performed in a batch of horse spleen ferritins from which iron had been gradually removed, yielding samples containing 2200, 1200, 500, and 200 iron a...

We simultaneously labeled ferritin with two Alexa Fluor fluorophores (AF350 and AF430). When both fluorophores label the same ferritin subunit, fluorescence resonance energy transfer (FRET) takes place from the excited AF350 to the acceptor AF430. By varying the number and the ratio of labeling fluorophores, we can modulate FRET such that the ferri...

The aim of this study was to measure the demineralization capacity of 37% phosphoric acid on bovine enamel at different time-points after bleaching with 30% carbamide peroxide. Five, 4 x 4-mm sections were obtained from the enamel of 10 bovine incisors. After applying 30% carbamide peroxide (Vivastyle) for 90 min, specimens were stored in artificia...

It is well known that some of the metal ions remain bound to apoferritin when incubating apoferritin with metal ions. In this study a structural insight, from X-ray absorption spectroscopy (XAS) and small angle X-ray scattering (SAXS) experiments, into the mechanism of inorganic core formation is presented. The results indicate that, in the case of...

We report a flexible route to chemically modify the ferritin nanomagnet. Two dye-labeled ferritins (red- and blue-ferritin) have been prepared by covalently coupling the derivatives of the reactive orange 16 and Remazol brilliant blue R, respectively, to the ferritin surface lysine residues. The study of the particles by transmission electron micro...

Cited By (since 1996): 17, Export Date: 20 December 2011, Source: Scopus, CODEN: EJICF, doi: 10.1002/ejic.200700606, Language of Original Document: English, Correspondence Address: Domínguez-Vera, J.M.; Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Granada, Fuentenueva s/n, 18071 Granada, Spain; email: josema@ugr.es, Refe...

The objective of this study was to measure the demineralization capacity of 10% and 20% citric acid and 17% EDTA after three time periods and to determine whether it was modified by the addition of 1% of commercial chlorhexidine (CHX). Three slices of 2-mm thickness were cut from the cervical third of the root of ten bovine incisors and sectioned i...

Ni and Co nanoparticles (average diameters 3 and 3.5 nm) have been prepared within the apoferritin cavity. The protein shell prevents bulk aggregation of the metal particles, rendering them water soluble. X-Ray diffraction, transmission electronic microscopy and magnetization measurements have been used for characterizing the nanoparticles. The mag...

Copper and CuFe Prussian Blue nanoparticles were prepared using a Cu-loaded apoferritin as a chemically and spatially confined environment for their construction. The reaction of Cu II-apoferritin with [Fe(CN) 6] 3- in the presence of urea produced nanoparticles of the CuFe Prussian-Blue derivative. Metals and metallic cores homogeneous size were f...

It has been traditionally considered that catechols release iron from ferritin by reduction to iron(II), which diffuses through the ferritin channels into the intracellular milieu where it participates in the Fenton reaction, producing highly toxic hydroxyl radicals. However, in the present work we have proved that the mechanism of the release of i...

A new and easy method for the preparation of 1,3,7,9-tetramethylpyrido-[2,3-d6,5-d]-dipyrimidine-2,4,6,8-tetrone is described. The structure of this compound has been solved by means of X-ray diffraction methods. The chemical characterization by spectral (mass, ultraviolet, infrared, and proton nuclear magnetic resonance) and thermal (thermogravime...

The reaction, in ethanol or water medium, of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Pd(II), and Pt(II) ions with isoorotic and 2-thioisoorotic acids (H3L) has allowed the isolation of complexes with the general formula MII(H2L)2·2H2O. These were characterized by means of elemental analysis, spectral techniques (UV-Vis-NIR, IR, EPR, 13C and...

The thermal behaviour of the complexes of theophylline with Co(II), Cu(II), Ag(I), Zn(II) and Cd(II) was studied by thermogravimetry (TG), differential scanning calorimetry (DSC) and IR spectroscopy.The complexes decompose in three steps, dehydration, deammination and decomposition of the anhydrous complexes to metal or metal oxide.

The thermal decomposition processes of 6-amino-2-thiouracil and its Co(II), Ni(II), Cu(I), Ag(I), Zn(II), Cd(II) and Hg(II) complexes ha been studied by TG and DSC techniques. Heats of dehydration have been calculated from the DSC curves. Infrared spectroscopy applied to some of these complexes heated in air has elucidated thc decomposition steps a...

Some metal-6-thioguanine complexes have been prepared and studied in aqueous solution by potentiometric methods. In addition to this, eight new solid metal complexes of 6-thioguanine have been prepared and characterized on the basis of elemental analysis and IR spectroscopy. The thermal behaviour of these compounds has been studied using TG and DSC...

Several complexes of xanthosine, 9-β-D-ribofuranosylxanthine (Xao) with 3d metal ions have been prepared. The new complexes appear to be generally monomeric, involving terminal N3-bonded Xao ligands. The thermal behaviour of these complexes has been studied by TG, DTG and DSC techniques.

The chlorohydrate of 2-thioxanthine has been prepared in an acid medium, as well as some Ag(I), Cd(II), Hg(II) and Hg(I) 2-thioxanthine complexes. These compounds have been characterized by spectroscopic techniques and thermal analysis.The thermal behaviour of 2-thioxanthine (TXH), its chlorohydrate (TXH2Cl) and the above complexes has been studied...

New 4-amino-5-nitroso-6-oxo-1,2,3,6-tetrahyaro-2-thiopyrimidine (TANH) complexes of Zn(II), Cd(II), Hg(II) and Hg(I) were prepared and their thermal behaviour was studied by TG and DSC techniques. The dehydration and deamination enthalpies of the corresponding complexes were calculated.

Hexachloroplatinates of xanthine (XH), theobromine (TBH), theophylline (TFH), 1,3,8-trimethyl-xanthine (TMH), caffeine (CF) and 8-ethyl-theophylline (ETH) have been synthesized and studied by IR, H-NMR, TG and DSC techniques. In all cases, the purine derivatives acts in monoprotonated for and is not bound to metal ion, forming a salt-like structure...

The influence of ionic strength and temperature on the ionization constants of 4-amino-1,6-dihydro-2-methylthio-5-nitroso-6-oxo-pyrimidine (MTH) has been determined.Stability constants for Fe(II), Co(II), Ni(II) and Cu(II) complexes of MTH at different ionic strengths and temperatures have also been calculated.

The thermodynamic protonation constants of 4-amino-1,6-dihydro-2-methylthio-5-nitroso-6-oxo-pyrimidine (MTH), 4-amino-5-nitroso-6-oxo-1,2,3,6,-tetrahydro-2-thiopyrimidine (TANH) and 2-thioxanthine (TXH) in aqueous media at 25, 30, 40 and 50 ± 0.1°C, have been determined potentiometrically by Bjerrum and Robinson's methods. The ionic strength was ma...

Some complexes |PdL2Cl2| (where L = xanthine, theophylline, theobromine, 3,8-dimethylxanthine, caffeine and 1,3,8-trimethylxanthine) have been prepared in acid medium. Their structure has been established from IR and 1H-NMR data. The thermal behaviour of these complexes has been studied by TG, DTG and DSC techniques. Heats of dehalogenation have be...