Development of a chitin/graphene oxide hybrid composite for the removal of pollutant dyes: Adsorption and desorption study

This work presents the synthesis of chitin (Chi) and chitin/graphene oxide (Chi:nGO) hybrid gels in mild conditions and their use as biosorbents in solid-liquid batch systems. The graphene oxide nanosheets, obtained from natural graphite through Hummers method, were characterized using FT-IR, ESR and pHpzc determination as a qualitative approach of the degree of exfoliation and oxidation. Two kinds of widely used dyes were tested: Remazol Black (RB) as an acid dye model and Neutral Red (NR) as a basic dye model. Adsorption assays results were analyzed using two and three parameters isotherm models. The maximum adsorption capacity (qm) for RB and NR were 9.3×10-2mmol/g and 57×10-2mmol/g being the first one reached by Chi and the second by the hybrid. Furthermore, the adsorption behavior over the time was evaluated through pseudo-first, pseudo-second, Elovich and Modified Freundlich models being the first one which described better all the cases except the adsorption of Remazol Black on chitin gel which follows an Elovich tendency. According to the pseudo-first order model, the uptake rates (k1) were between 1.1×10-2min-1 and 1.4×10-2min-1, but for the Chi:nGO-NR system it was 1.7×10-3min-1. The adsorption was observed to be dependent on both the solution pH and the Chi:nGO proportion. Finally, both dyes can be desorbed from both kinds of materials up to 60% of the sorbed amount by increasing the solution pH above 8. This would imply the capability of reutilization of the material with minor sorption capacity.Fil: González, Joaquín Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Villanueva, María Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Piehl, Lidia Leonor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Copello, Guillermo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; Argentin

Effect of DHEA and metformin on corpus luteum in mice

Effect of DHEA and metformin on corpus luteum in mice Abstract We evaluated the effect of hyperandrogenism in ovaries with functional and regressing corpora lutea (CL) and the action of metformin in preventing these possible alterations using a mouse model. To obtain a CL functional for 9+/-1 days, immature female mice of the BALB/c strain were injected i.p. with 10 IU/mouse of pregnant mare´s serum gonadotropin (PMSG). DHEA (60 mg/kg body weight s.c., 24 and 48 h prior to kill) decreased both serum progesterone (P) and estradiol (E(2)) levels and increased the activity of superoxide dismutase (SOD) from ovaries with functional CL (on day 5 after PMSG). It increased P and E(2) and the activities of SOD and catalase (CAT) and decreased lipoperoxidation of ovaries with regressing CL (on day 9 after PMSG). Treatment with DHEA did not affect the production of prostaglandin F(2alpha) (PGF(2alpha)) or PGE by ovaries with functional CL, whereas DHEA decreased PGF(2alpha) and increased PGE production by ovaries with regressing CL. Metformin (50 mg/kg body weight, orally) given together with DHEA restored E(2) levels from mice with ovaries with functional CL and serum P, PGF(2alpha) and PGE levels, and oxidative balance in mice with ovaries with regressing CL. Metformin alone was able to modulate serum P and E(2) levels, lipoperoxidation, SOD and CAT, and the 5,5-dimethyl-1-pyrroline N-oxide/(*)OH signal. These findings suggest that hyperandrogenism is able to induce or to rescue CL from luteolysis and metformin treatment is able to prevent these effects.Fil: Sander, Valeria Analía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas (subsede Chascomús) | Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas (subsede Chascomús); ArgentinaFil: Facorro, Graciela. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Físico Matemática; ArgentinaFil: Piehl, Lidia Leonor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Físico Matemática; ArgentinaFil: Rubin de Cellis, E. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Motta, Alicia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentin

Chitin based hybrid composites reinforced with graphene derivatives: a nanoscale study

In this work, we present two novel nanostructured hybrid materials based on a chitin matrix loaded with increasing amounts of graphene oxide and reduced graphene oxide nanosheets (nGO and rGO, respectively). Both kinds of material (Chi:nGO and Chi:rGO) were studied using different spectroscopic and rheological techniques with the aim of understanding the interaction mechanism between chitin and nGO/rGO and explaining how the type of filler and its proportion affects its reinforcement. The production of these hybrids represents not only the obtention of low-cost materials with mechanical resistance but also a good opportunity for developing materials with several applications according to their composition. The nGO and rGO were characterised through FT-IR and ESR for the determination of the oxidation degree of each nanofiller. Then, the hybrids were spectroscopically analysed with FT-IR, ESR and SAXS which demonstrated that the components do not interact through covalent bonding and the nanosheets are well-dispersed among the chitin matrix. Finally, a rheological behavior assay was performed and its results were analysed in terms of G′ and η*. In short, all the results allowed us to conclude that nGO acts as a more efficient reinforcer than rGO due to the higher amount of hydrogen bonding established with chitin.Fil: González, Joaquín Antonio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco (i); ArgentinaFil: Villanueva, María Emilia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco (i); ArgentinaFil: Peralta Ramos, María Luz. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco (i); ArgentinaFil: Pérez, Claudio Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); ArgentinaFil: Piehl, Lidia Leonor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Copello, Guillermo Javier. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco (i); Argentin

Boar seminal plasma exosomes: Effect on sperm function and protein identification by sequencing

Mammalian seminal plasma contains membranous vesicles (exosomes), with a high content of cholesterol and sphingomyelin and a complex protein composition. Their physiological role is uncertain because sperm stabilization and activation effects have been reported. To analyze a putative modulatory role for semen exosomes on sperm activity in the boar, the effects of these vesicles on several sperm functional parameters were examined. Additionally, boar exosome proteins were sequenced and their incorporation into sperm was explored. Boar sperm were incubated under conditions that induce capacitation, manifested as increased tyrosine phosphorylation, cholesterol loss and greater fluidity in apical membranes, and the ability to undergo the lysophosphatidylcholine-induced acrosome reaction. After establishing this cluster of capacitation-dependent functional parameters, the effect produced by exosomes when present during or after sperm capacitation was analyzed. Exosomes inhibited the capacitation-dependent cholesterol efflux and fluidity increase in apical membranes, and the disappearance of a 14-kD phosphorylated polypeptide. In contrast, the acrosome reaction (spontaneous and lysophosphatidylcholine-induced) was not affected, and sperm binding to the oocyte zona pellucida was reduced only when vesicles were present during gamete coincubation. Liposomes with a lipid composition similar to that present in exosomes mimicked these effects, except the one on zona pellucida binding. Interaction between exosomes and sperm was confirmed by transfer of aminopeptidase activity. In addition, the major exosome protein, identified as actin, appeared to associate with sperm after coincubation. Exosome composition had a predominance for structural proteins (actin, plastin, ezrin, and condensin), enzymes, and several porcine seminal plasma-specific polypeptides (e.g., spermadhesins). Transfer of proteins from exosome to sperm and their ability to block cholesterol efflux supports a direct interaction between these vesicles and sperm, whereas inhibition of some capacitation-dependent features suggests a stabilizing function for exosomes in boar semen.Fil: Piehl, Lidia Leonor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Fischman, Maria Laura. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Instituto de Investigacion y Tecnología en Reproducción Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hellman, Ulf. Ludwig Institute for Cancer Research; SueciaFil: Cisale, Humberto Osvaldo. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Instituto de Investigacion y Tecnología en Reproducción Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Miranda, Patricia Vivian. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin

Effect of serum lipoproteins and cholesterol on an exogenous pulmonary surfactant: ESR analysis of structural changes and their relation with surfactant activity

The study of structural changes in the surfactant may help to understand the mechanisms by which the surfactant is inactivated by serum. Here, we compared the in vitro effects of serum, albumin, lipoproteins (VLDL, LDL, HDL) and cholesterol on the dynamic and structural properties of surfactant suspensions by electronic spin resonance and surface tension measurements. Our results showed that albumin seems to be responsible for macrostructure disaggregation and increased rigidity in the hydrophobic region, but it did not affect surfactant activity. Fluidity in the polar area seems to be critical for proper physiological activity, and the changes induced by serum observed in this area would be generated by HDL or cholesterol, but the amount of cholesterol transferred by serum is not significant. Statistical analysis showed that surfactant activity correlated with the fluidity in the polar area but not with that in the hydrophobic region. We obtained strong evidence that among all the serum components tested, HDL is the one that causes the structural changes that compromise surfactant performance.Fil: Martínez Sarrasague, María Margarita. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Cimato, Alejandra Noemí. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Piehl, Lidia Leonor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; ArgentinaFil: Brites, Fernando Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Bioquímica Clínica; ArgentinaFil: Facorro, Graciela. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Fisicomatemática. Cátedra de Física; Argentin

New Insights about the Selectivity in the Activation of Hydrogen Peroxide by Cobalt or Copper Hydrogel Heterogeneous Catalysts in the Generation of Reactive Oxygen Species

We report the performance of Co(II) and Cu(II) coordination complexes on H2O2 activation. The heterogeneous catalysts containing aliphatic amine, N-heterocycle, and/or carboxylic acid ligands in hydrogel materials coordinated with Co(II) or Cu(II) were used in this study. These complexes were characterized by solid-state NMR, X-ray photoelectron spectroscopy (XPS), and X-ray fluorescence techniques in order to quantify the superficial and bulk metal ion centers together with the aim of elucidating the ligands involved in the uptake of Co and Cu ions. The release of free radicals on H2O2 activation and the identity of reactive oxygen species were studied by spin trapping using DMPO in electron spin resonance (ESR) experiments. The Co(II) complex/H2O2 systems produced O2, anion superoxide (O2•–), and hydroxyl radical (OH•), which diffused into the solution at the time that a decrease in pH was detected. A possible catalytic mechanism would involve the Co(II)/Co(III) redox couple, according to XPS results. In the same way, the Cu(II) complex/H2O2 systems produced O2 and OH•, with evidence of Cu(II)/Cu(I) redox cycle. For these catalytic systems, there was no direct evidence of intermediary reactive species. The identity of the ligands played a crucial role in the efficiency of catalytic activation. In addition, in the absence of H2O2, the dissolved O2 was activated by most of the complexes tested, releasing only OH•.Fil: Lazaro Martinez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas ; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; ArgentinaFil: Lombardo Lupano, Lucía Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas ; ArgentinaFil: Piehl, Lidia Leonor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Físico Matemática; ArgentinaFil: Rodríguez Castellón, Enrique. Universidad de Málaga; EspañaFil: Campodallorto, Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas ; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentin

Activation of H2O2 and superoxide production using a novel cobalt complex based on a polyampholyte

A new catalyst based on Co(II) and a hydrogel with property of polyampholyte was characterized by equilibrium studies of Co(II) uptake, solid-state NMR and energy dispersive X-ray analysis. The matrix derived from methacrylic acid and 2-methylimidazole is easily synthesized in one-spot strategy, and combines coordination properties with chemical resistance. The catalytic activity of this material on H2O2 activation was studied by electron spin resonance, which confirmed the release of superoxide radical. A possible mechanism of interaction involves the simultaneous production of dioxygen, protons and water. The catalytic performance was assessed in the activation of H2O2 for the oxidation of two representative organic compounds of environmental concern. About 70% of methyl orange, a model azo dye, was removed from distilled water in 2 h by oxidation with H2O2 60 mM and by adsorption on the catalyst. The amount of adsorbed dye was minimized in the presence of 0.1 M Na2SO4. The kinetics of the processes followed a pseudo-first-order empirical model, and the catalyst was recovered and re-used. Epinephrine was chosen as a pharmaceutical model susceptible to superoxide attack. About 80% of conversion to adrenochrome was reached in less than 6 min, following a pseudo-first-order kinetic model.Fil: Lombardo Lupano, Lucía Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas ; ArgentinaFil: Lazaro Martinez, Juan Manuel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Piehl, Lidia Leonor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Físico Matemática; ArgentinaFil: Rubín de Celis, Emilio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Físico Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Campodallorto, Viviana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas ; Argentin

Synthesis, Characterization, and Catalytic Properties of Cationic Hydrogels Containing Copper(II) and Cobalt(II) Ions

Here, we report the synthesis and characterization of a hydrogel based on ethylene glicol diglycidyl ether (EGDE) and 1,8-diamino-3,6-dioxaoctane (DA). Chemically stable Co(II) and Cu(II) coordination complexes were prepared with this non-soluble polyelectrolyte, Poly(EGDE-DA), and studied by ss-NMR, FTIR, thermogravimetry and microscopy. Mesopores were found in all the samples, the thermal stability of the polymer matrix was highly affected by the presence of metal ions, and the 13C CP-MAS spectrum for the Cu(II)-complex evidenced a significant increase in the reticulation degree by Cu(II) ions. The catalytic activity of these materials on H2O2 activation was studied by Electron Spin Resonance (ESR). The Co(II)-Poly(EGDE-DA) / H2O2 heterogeneous system produced O2, anion superoxide (O2*¯) and hydroxyl radical (OH*), which diffused into the solution at the time that a decrease in pH was detected. In the same way, the Cu(II)-Poly(EGDE-DA) / H2O2 heterogeneous system produced O2 and OH*. H2O2 activation by the Poly(EGDE-DA) complexes with Co(II) and Cu(II) was applied on the decolorization of solutions of the azo-dye Methyl Orange (MO). In the presence of 63 mM H2O2, 87 % of MO was removed in 10 min with Cu(II)-Poly(EGDE-DA) and in 110 min with Co(II)-Poly(EGDE-DA). In addition, the pharmaceutical product epinephrine was partially oxidized to adrenochrome by the O2*¯ released from the Co(II)-Poly(EGDE-DA) / H2O2 heterogeneous system.Fil: Lombardo Lupano, Lucía Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; ArgentinaFil: Lazaro Martinez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; ArgentinaFil: Piehl, Lidia Leonor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Físico Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Rubín de Celis, Emilio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Físico Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Torres Sanchez, Rosa Maria. Provincia de Buenos Aires. Gobernación. Comision de Invest.científicas. Centro de Tecnología de Recursos Minerales y Ceramica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Tecnología de Recursos Minerales y Ceramica; ArgentinaFil: Campodallorto, Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentin

Polyphenol-SiO2 hybrid biosorbent for heavy metal removal. Yerba mate waste (Ilex paraguariensis) as polyphenol source: Kinetics and isotherm studies

A low-cost biosorbent hybrid material ready for application was obtained in this work. Yerba mate (Ilex paraguariensis) milling residual dust was used as a polyphenol source by ethanolic extraction. Polyphenols were immobilized within a SiO2 matrix to form an interpenetrated polymer after glutaraldehyde cross-linking. Pb(II), Cr(III) and Cr(VI) were chosen as model metals for adsorption. The hybrid materials were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS) and Nitrogen Adsorption Isotherms. Adsorption experimental data were analysed using Langmuir, Freundlich, Dubinin-Radushkevich, Temkin, Redlich-Peterson, Sips and Toth isotherm models along with the evaluation of adsorption energy and standard free energy (ΔG°). The adsorption was observed to be pH dependent. The main mechanism of metal adsorption was found to be a spontaneous charge associated interaction. Electron Spin Resonance (ESR) spectroscopy confirmed that Cr(VI) adsorption was an adsorption-coupled reaction and the adsorbed specie was Cr(V). The hybrid matrix probed its adsorption capacity of Cr(III) in a non-treated tannery wastewater.Fil: Copello, Guillermo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; ArgentinaFil: Pesenti, M. P.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; ArgentinaFil: Raineri Andersen, Mariana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mebert, Andrea Mathilde. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Piehl, Lidia Leonor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; ArgentinaFil: Rubín de Celis, Emilio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; ArgentinaFil: Diaz, L. E.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; Argentin