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1.
Int J Mol Sci ; 24(3)2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36768774

RESUMEN

Shape memory alloys, especially ferromagnetic shape memory alloys, are interesting new materials for the manufacturing of stents. Iron-palladium alloys in particular can be used to manufacture self-expanding temporary stents due to their optimum rate of degradation, which is between that of magnesium and pure iron, two metals commonly used in temporary stent research. In order to avoid blood clotting upon the introduction of the stent, they are often coated with anticoagulants. In this study, sulfated pectin, a heparin mimetic, was synthesized in different ways and used as coating on multiple iron-palladium alloys. The static and dynamic prothrombin time (PT) and activated partial thromboplastin time (APTT) of the prepared materials were compared to samples uncoated or coated with polyethylene glycol. While no large differences were observed in the prothrombin time measurements, the activated partial thromboplastin time increased significantly with all alloys coated with sulfated pectin. Aside from that, sulfated pectin synthesized by different methods also caused slight changes in the activated partial thromboplastin time. These findings show that iron-palladium alloys can be coated with anticoagulants to improve their utility as material for temporary stents. Sulfated pectin was characterized by nuclear magnetic resonance (NMR) and Fourier-transform infrared (FTIR) spectroscopy, and the coated alloys by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX).


Asunto(s)
Anticoagulantes , Aleaciones con Memoria de Forma , Paladio , Propiedades de Superficie , Aleaciones/química , Hierro , Materiales Biocompatibles Revestidos/farmacología , Materiales Biocompatibles Revestidos/química
2.
Pharmaceuticals (Basel) ; 14(5)2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34062744

RESUMEN

Three-dimensional printing (3DP) by fused deposition modeling (FDM) has gained momentum as a promising pharmaceutical manufacturing method due to encouraging forward-looking perspectives in personalized medicine preparation. The current challenges the technology has for applicability in the fabrication of solid dosage forms include the limited range of suitable pharmaceutical grade thermoplastic materials. Hence, it is important to investigate the implications of variable properties of the polymeric carrier on the preparation steps and the final output, as versatile products could be obtained by using the same material. In this study, we highlighted the influence of polyvinyl alcohol (PVA) particle size on the residence time of the mixtures in the extruder during the drug-loaded filament preparation step and the consequent impact on drug release from the 3D printed dosage form. We enhanced filament printability by exploiting the plasticizing potential of the active pharmaceutical ingredient (API) and we explored a channeled tablet model as a design strategy for dissolution facilitating purposes. Our findings disclosed a new perspective regarding material considerations for the preparation of PVA-based solid dosage forms by coupling hot melt extrusion (HME) and FDM-3DP.

3.
J Hazard Mater ; 403: 123528, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-32771814

RESUMEN

The nanocomposite CNT-COOH/MnO2/Fe3O4 was synthesized and characterized by different techniques, namely X-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, energy dispersive spectroscopy, thermogravimetric analysis, Brunauer-Emmett-Teller analysis, magnetic measurement, point of zero charge and hydrophobicity index. Analyzes revealed the groups -COOH, MnO2 and Fe3O4 attached to the carbon nanotubes, the acidic character of the obtained nanocomposite and its stability. The surface area for the obtained nanocomposite was 114.2 m2 g-1. The prepared nanocomposite was used for adsorption of ibuprofen and paracetamol from aqueous solution. Isotherm, kinetic and thermodynamic parameters were determined for predicting the ibuprofen and paracetamol adsorption on synthetized nanocomposite. The equilibrium data obtained from adsorption were well represented by Langmuir model and kinetics data were well fitted by the pseudo-second order model. The maximum adsorption capacity obtained for ibuprofen and paracetamol was 103.093 mg g-1, 80.645 mg g-1 respectively. The thermodynamic analysis showed that the adsorption process for both pollutants was spontaneous and endothermic. The synthetized nanocomposite can be a suitable new absorbent for ibuprofen and paracetamol removal from aqueous solutions due to its high adsorbing capacity and it can be separated by an external magnetic field.


Asunto(s)
Nanocompuestos , Nanotubos de Carbono , Contaminantes Químicos del Agua , Acetaminofén , Adsorción , Concentración de Iones de Hidrógeno , Ibuprofeno , Cinética , Compuestos de Manganeso , Óxidos , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Contaminantes Químicos del Agua/análisis
4.
Bioresour Technol ; 315: 123794, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32712512

RESUMEN

A logical framework was used for designing a top-down strategy for cyanobacterial phycobiliprotein purification. The purification scheme is based on the non-chromatographic technique, known as aqueous two-phase system. The scheme was optimized at every stage to enhance the recovery yield with the highest purity. We tested this strategy on four cyanobacteria, two containing only phycocyanin and allophycocyanin (Arthrospira platensis AICB49, Synechocystis sp. AICB51) and two that have an extra phycobiliprotein, namely phycoerythrin (Fremyella sp. UTEX481, Coelomoron pussilum AICB1012). The results showed that the recovery efficiency of the phycobiliproteins is strongly influenced by the phycobilisome composition. For the first two strains the recovery yield of both phycocyanin and allophycocyanin was >80%, with an analytical purity grade for phycocyanin (>4.2) and a reactive purity grade for allophycocyanin (>2.9). The recovery yield of phycoerythrin was lower but compensating with an increase in purity, 5.2 for Fremyella and 4.5 for C. pussilum.


Asunto(s)
Ficobiliproteínas , Spirulina , Ficobilisomas , Ficocianina , Ficoeritrina
5.
Data Brief ; 25: 104165, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31317064

RESUMEN

In this data article, we present supplementary data related to the research article entitled "Starch-coated green synthesized magnetite nanoparticles for removal of textile dye Optilan Blue from aqueous media" Stan et al., 2019. Data interpretations are included in the related research article Stan et al., 2019. The synthesized starch-coated Fe3O4 nanoparticles (ST-coated Fe3O4 NPs) were analyzed by scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) to illustrate the shape and surface coating of nanoparticles. Moreover, the Brunauer-Emmett-Teller (BET) technique was used to evidence starch deposition on magnetite nanoparticles. The obtained nanocomposites were used for adsorption of Optilan Blue (OB) in batch conditions and the optimum agitation speed and point of zero charge (pHpzc) were established. After OB adsorption on ST-coated Fe3O4 NPs, the nanocomposites were analyzed by transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The stability of starch coated Fe3O4 NPs in the acidic as well as alkaline pH was also evidenced by FTIR spectroscopy. In addition, to test the stability of ST-coated Fe3O4 NPs, leaching experiments were carried out. The experimental data were compared with isotherm and kinetic models in order to determine the most suitable for fitting.

6.
Crit Rev Anal Chem ; 47(6): 499-512, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-28541711

RESUMEN

The world is in the midst of a pre-emptive public health emergency, one that is just as dramatic as the global aggressive viruses-related crises (Ebola, Zika, or SARS), but not as visible. The "superbugs" and their antimicrobial resistance do not cause much public alarm or awareness, but provoke financial losses of $100 trillion annually (WHO, http://www.who.int/mediacentre/commentaries/superbugs-action-now/en/ ). This status quo review offers an overview of ultrasensitive methods for high-throughput monitoring of bacteria during infection treatment, the effects of antibiotics on bacteria at single-cell level and the challenges we will face in their detection due to the extraordinary capability of these "superbugs" to gain and constantly improve multiresistance to antibiotics. A special emphasis is put on the ultrasensitive spectroscopic-based analysis techniques, using nanotechnology or not necessarily, that are more and more promising alternatives to conventional culture-based ones. The particular case of Mycobacteria detection is discussed based on recent reported work.


Asunto(s)
Bacterias/química , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/microbiología , Humanos , Nanopartículas del Metal/química , Microscopía Electrónica de Transmisión , Plata/química , Análisis de la Célula Individual , Espectrometría Raman
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