The aim of this study was to characterize the solid state properties of (4E)-2-(1H-pyrazol-3-ylam... more The aim of this study was to characterize the solid state properties of (4E)-2-(1H-pyrazol-3-ylamino)-4-(1H-pyrazol-3-ylimino)naphthalen-1(4H)-one (BiPNQ), a compound with a significant inhibitory activity against Trypanosoma cruzi, the etiological agent of Chagas disease (American trypanosomiasis). Methods used included Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Fourier Transform Infrared Spectroscopy (FTIR), Powder X-Ray Diffraction (PXRD), Hot Stage, and Confocal Microscopy. Two BiPNQ samples were obtained by crystallization from absolute methanol and 2-propanol-water that exhibited different thermal behaviours, PXRD patterns, and FTIR spectra, indicating the existence of an anhydrous form (BiPNQ-I) and a solvate (BIPNQ-s), which on heating desolvated leading to the anhydrous modification BiPNQ-I. It was determined that FTIR, DSC, and PXRD are useful techniques for the characterization and identification of the crystalline modifications of BiPNQ.
This work presents a fast and reliable electroanalytical procedure for the quantification of azit... more This work presents a fast and reliable electroanalytical procedure for the quantification of azithromycin (AZ) in different systems that couples flow injection analysis and amperometric detection (FIA-AM). The quantification was performed at a working potential of 1.20 V (vs Ag/AgCl/NaCl (3 M)) in 0.05 M phosphate buffer at a flow rate of 1.0 mL min −1 . Under these conditions a 1.00 × 10 −6 −1.50 × 10 −5 M linear range, (5.8 ± 0.4) × 10 4 C AZ (μA M −1 ) sensitivity and 4.44 × 10 −7 M limit of detection are obtained. Also, this technique can be used without sample pretreatment and presents good reproducibility. The procedure was applied to the determination of the content of AZ in commercial tablets, to study the intrinsic dissolution rate of compacts of AZ dihydrate, and to determine the AZ release from a AZ hydrogel and carbomer. The method was statistically analyzed and proves to be reliable and robust. However, more remarkable is that FIA-AM technique presents better sensitivity and high sampling rate. Figure 1. Chemical structure of azithromycin. Article pubs.acs.org/IECR
Latex, a polyisoprene (PI) hydrophobic elastomer, was evaluated in vitro and in vivo as a matrix ... more Latex, a polyisoprene (PI) hydrophobic elastomer, was evaluated in vitro and in vivo as a matrix for intravaginal steroid hormone delivery. Matrices containing hormone were prepared by swelling latex in chloroform that contained soluble progesterone (P4). In vitro studies demonstrate that P4 release from PI follows a zero order model during at least 100 h and depends on initial load up to 10 mg cm(-2). The release of P4 from a PI matrix was found to be two times faster than from a polydimethylsiloxane (PDMS) matrix. FT-IR and X-ray powder diffraction analysis of P4 polymorphs show that when nucleated in PDMS, the hormone crystallizes only in alpha-form while in latex, crystallizes as a mixture of alpha- and beta-form. In vivo studies show that devices with a PI matrix containing 0.5 g of P4 are effective to reach plasma levels above 1 ng ml(-1) that are needed to synchronize estrous in cattle. Altogether, the results show that PI, a vulcanized polymer with a carbon-carbon backbone, ...
Solid-state physical characterization of a pharmaceutical substance is necessary for successful d... more Solid-state physical characterization of a pharmaceutical substance is necessary for successful development and approval of the final product. Different physical analytical techniques are available to do so: X-ray diffraction (XRD), IR, Raman, DSC, TG and NMR. Moreover, all of them detect the presence of excipients perturbing the analysis of the pure substance in low doses. In order to study polymorphism and pseudo polymorphism of drug, this paper introduces possible applications of pure nuclear quadrupole resonance, as a non-destructive technique in qualitative and quantitative approaches. Chlorpropamide and diclofenac sodium were used as examples. Unlike the mentioned techniques, the nuclear quadrupole resonance (NQR) signal of pharmaceutical compounds is not perturbed by the presence of solid excipient or other substances unless they possess resonance frequencies in the same frequency range of the compound studied.
A study of level of Pb in soils of the centre-north of the Province of Córdoba, a worldwide recog... more A study of level of Pb in soils of the centre-north of the Province of Córdoba, a worldwide recognized tourist region for dove hunting, was performed in this work. The native forest of the region has a great population of doves associated with the grains productive fields of the surrounding. Contamination of soils due to hunting activities is regulated by national and local norms. The Córdoba Environmental Secretary by resolution Nº 1115/2011 approved a new regulation that categorizes this activity as generator of Y31 (Pb) industrial waste. Lead from pellets alloy is deposited on the soil of the shooting fields. Samples were taken at depth of 50 mm from 315 pits referenced by GPS in accordance with local environmental authorities as well as the hunting outfitters companies. Sampling sites are distributed between parallels 31 ºS (S31) up to 30 ºS (S30) and between meridians W64 up to W63. Soils samples were analysed by Xray fluorescence spectroscopy (XRF) while Pb bullets were analysed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The average concentration obtained for Pb in dry soil sieved (200 mesh) was 80 ppm. Powder XRD patterns of crust material removed from the corroded surface of weathered bullets were obtained.
Acta Crystallographica Section E Structure Reports Online, 2008
Key indicators: single-crystal X-ray study; T = 150 K; mean (C-C) = 0.004 Å; disorder in main res... more Key indicators: single-crystal X-ray study; T = 150 K; mean (C-C) = 0.004 Å; disorder in main residue; R factor = 0.075; wR factor = 0.237; data-to-parameter ratio = 14.1.
The aim of this study was to characterize the solid state properties of (4E)-2-(1H-pyrazol-3-ylam... more The aim of this study was to characterize the solid state properties of (4E)-2-(1H-pyrazol-3-ylamino)-4-(1H-pyrazol-3-ylimino)naphthalen-1(4H)-one (BiPNQ), a compound with a significant inhibitory activity against Trypanosoma cruzi, the etiological agent of Chagas disease (American trypanosomiasis). Methods used included Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Fourier Transform Infrared Spectroscopy (FTIR), Powder X-Ray Diffraction (PXRD), Hot Stage, and Confocal Microscopy. Two BiPNQ samples were obtained by crystallization from absolute methanol and 2-propanol-water that exhibited different thermal behaviours, PXRD patterns, and FTIR spectra, indicating the existence of an anhydrous form (BiPNQ-I) and a solvate (BIPNQ-s), which on heating desolvated leading to the anhydrous modification BiPNQ-I. It was determined that FTIR, DSC, and PXRD are useful techniques for the characterization and identification of the crystalline modifications of BiPNQ.
This work presents a fast and reliable electroanalytical procedure for the quantification of azit... more This work presents a fast and reliable electroanalytical procedure for the quantification of azithromycin (AZ) in different systems that couples flow injection analysis and amperometric detection (FIA-AM). The quantification was performed at a working potential of 1.20 V (vs Ag/AgCl/NaCl (3 M)) in 0.05 M phosphate buffer at a flow rate of 1.0 mL min −1 . Under these conditions a 1.00 × 10 −6 −1.50 × 10 −5 M linear range, (5.8 ± 0.4) × 10 4 C AZ (μA M −1 ) sensitivity and 4.44 × 10 −7 M limit of detection are obtained. Also, this technique can be used without sample pretreatment and presents good reproducibility. The procedure was applied to the determination of the content of AZ in commercial tablets, to study the intrinsic dissolution rate of compacts of AZ dihydrate, and to determine the AZ release from a AZ hydrogel and carbomer. The method was statistically analyzed and proves to be reliable and robust. However, more remarkable is that FIA-AM technique presents better sensitivity and high sampling rate. Figure 1. Chemical structure of azithromycin. Article pubs.acs.org/IECR
Latex, a polyisoprene (PI) hydrophobic elastomer, was evaluated in vitro and in vivo as a matrix ... more Latex, a polyisoprene (PI) hydrophobic elastomer, was evaluated in vitro and in vivo as a matrix for intravaginal steroid hormone delivery. Matrices containing hormone were prepared by swelling latex in chloroform that contained soluble progesterone (P4). In vitro studies demonstrate that P4 release from PI follows a zero order model during at least 100 h and depends on initial load up to 10 mg cm(-2). The release of P4 from a PI matrix was found to be two times faster than from a polydimethylsiloxane (PDMS) matrix. FT-IR and X-ray powder diffraction analysis of P4 polymorphs show that when nucleated in PDMS, the hormone crystallizes only in alpha-form while in latex, crystallizes as a mixture of alpha- and beta-form. In vivo studies show that devices with a PI matrix containing 0.5 g of P4 are effective to reach plasma levels above 1 ng ml(-1) that are needed to synchronize estrous in cattle. Altogether, the results show that PI, a vulcanized polymer with a carbon-carbon backbone, ...
Solid-state physical characterization of a pharmaceutical substance is necessary for successful d... more Solid-state physical characterization of a pharmaceutical substance is necessary for successful development and approval of the final product. Different physical analytical techniques are available to do so: X-ray diffraction (XRD), IR, Raman, DSC, TG and NMR. Moreover, all of them detect the presence of excipients perturbing the analysis of the pure substance in low doses. In order to study polymorphism and pseudo polymorphism of drug, this paper introduces possible applications of pure nuclear quadrupole resonance, as a non-destructive technique in qualitative and quantitative approaches. Chlorpropamide and diclofenac sodium were used as examples. Unlike the mentioned techniques, the nuclear quadrupole resonance (NQR) signal of pharmaceutical compounds is not perturbed by the presence of solid excipient or other substances unless they possess resonance frequencies in the same frequency range of the compound studied.
A study of level of Pb in soils of the centre-north of the Province of Córdoba, a worldwide recog... more A study of level of Pb in soils of the centre-north of the Province of Córdoba, a worldwide recognized tourist region for dove hunting, was performed in this work. The native forest of the region has a great population of doves associated with the grains productive fields of the surrounding. Contamination of soils due to hunting activities is regulated by national and local norms. The Córdoba Environmental Secretary by resolution Nº 1115/2011 approved a new regulation that categorizes this activity as generator of Y31 (Pb) industrial waste. Lead from pellets alloy is deposited on the soil of the shooting fields. Samples were taken at depth of 50 mm from 315 pits referenced by GPS in accordance with local environmental authorities as well as the hunting outfitters companies. Sampling sites are distributed between parallels 31 ºS (S31) up to 30 ºS (S30) and between meridians W64 up to W63. Soils samples were analysed by Xray fluorescence spectroscopy (XRF) while Pb bullets were analysed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The average concentration obtained for Pb in dry soil sieved (200 mesh) was 80 ppm. Powder XRD patterns of crust material removed from the corroded surface of weathered bullets were obtained.
Acta Crystallographica Section E Structure Reports Online, 2008
Key indicators: single-crystal X-ray study; T = 150 K; mean (C-C) = 0.004 Å; disorder in main res... more Key indicators: single-crystal X-ray study; T = 150 K; mean (C-C) = 0.004 Å; disorder in main residue; R factor = 0.075; wR factor = 0.237; data-to-parameter ratio = 14.1.
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Papers by Sonia Faudone