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Stelian Vlad - One of the best experts on this subject based on the ideXlab platform.
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molecular dynamics conductivity and morphology of Sodium Deoxycholate based poly ester ether urethane ionomer biomaterials
Journal of Materials Science, 2016Co-Authors: Daniela Filip, Doina Macocinschi, Mihai Asandulesa, M Aflori, Stelian VladAbstract:Broad-band dielectric spectroscopy technique was used to investigate the molecular dynamics of new Sodium Deoxycholate-based poly(ester ether)urethane ionomers of particular interest in biomedical devices. These polyurethane ionomers have identical hard segment containing bile salt moiety but with different soft segment chemistries. Poly(ethylene oxide)-rich soft segment promotes stronger ionic interactions and solvation capacity of ions and higher ionic conductivity in these polyurethane ionomers. The universal power law was employed to study the evolution of alternating conductivity (AC) with frequency and temperature. The calculated values of fractional exponent ranged between 0 and 1 which indicate AC conduction through hopping mechanism. Direct current conductivity evidences Arrhenius behaviour in the function of temperature and the estimated values of activation energy for poly(ethylene oxide)-rich soft segment polyurethane ionomers are found higher. The increase in the conductivity with temperature can be interpreted as a hopping mechanism assisted by chain relaxation. AFM and SAXS investigations evidence lamellar arrangement at the sub-micron scale and the nanophase-separated morphology for these polyurethane ionomers. The tensile tests evidenced that the polyurethane with highest molecular weight exhibits the highest values of mechanical properties and ductile behaviour.
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surface characterization and antimicrobial properties of Sodium Deoxycholate based poly ester ether urethane ionomer biomaterials
Reactive & Functional Polymers, 2016Co-Authors: Daniela Filip, Elena Paslaru, Cristina Gabriela Tuchilus, Doina Macocinschi, Stelian VladAbstract:Abstract New Sodium Deoxycholate-based poly(ester ether)urethane ionomers have been obtained for the development of biomedical materials. Wettability, surface tension parameters, surface morphology, roughness, water sorption and/or desorption properties, and antimicrobial efficiency were determined for the obtained polyurethane biomembranes. Contact angle analysis evidenced that the synthesized polyurethane ionomers are hydrophilic due to orientation and amount of ionic bile salt moieties towards surface. The values of interfacial tension demonstrate biocompatible qualities for these polyurethanes. SEM microphotographs show that the resulted morphologies of polyurethane ionomers are different due to the diverse polyether co-soft segments which determine the supramolecular architecture, ionic interactions between bile salt moiety and polyether segments. AFM images evidence lamellar arrangement at the sub-micron scale and the nanophase separated morphology for these polyurethanes. The estimated moisture diffusion coefficients are dependent on a range of moisture transport mechanisms in the porous membranes and the moisture content of the polyurethanes. The monolayer sorption and average pore size values were estimated by applying BET and GAB models. GAB model could not be applied in the case of high water uptake polyurethane samples. The synthesized biocidal polyurethanes are effective at inactivation of tested bacteria: Staphylococcus aureus, Sarcina lutea, Escherichia coli, except Pseudomonas aeruginosa.
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structure property relationship of Sodium Deoxycholate based poly ester ether urethane ionomers for biomedical applications
Journal of Applied Polymer Science, 2016Co-Authors: Daniela Filip, Mariana Cristea, Gabriela Lisa, Stelian Vlad, Doina Macocinschi, Mirela F. ZaltariovAbstract:New Sodium Deoxycholate based poly(ester ether)urethane ionomers were prepared for the development of biomedical materials. A structure–property relationship in the tested biomaterials was established by cross-examination of the dynamic mechanical and dielectric properties, attenuated total reflection–Fourier transform infrared investigation, thermogravimetric analysis, and surface morphology characterization. A stronger ionic interaction and solvation capacity of the ions and a higher ionic conductivity were manifested in the case of poly(ethylene oxide)-rich segments than for poly(propylene oxide)-rich segments in these polyurethane ionomers. The molecular and ionic interactions of the bile-salt moiety with different polyether cosoft segments influenced chain packing and conformation, supramolecular organization, and the resulting surface morphological microstructures of the polyurethane biomembranes. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42921.
Daniela Filip - One of the best experts on this subject based on the ideXlab platform.
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molecular dynamics conductivity and morphology of Sodium Deoxycholate based poly ester ether urethane ionomer biomaterials
Journal of Materials Science, 2016Co-Authors: Daniela Filip, Doina Macocinschi, Mihai Asandulesa, M Aflori, Stelian VladAbstract:Broad-band dielectric spectroscopy technique was used to investigate the molecular dynamics of new Sodium Deoxycholate-based poly(ester ether)urethane ionomers of particular interest in biomedical devices. These polyurethane ionomers have identical hard segment containing bile salt moiety but with different soft segment chemistries. Poly(ethylene oxide)-rich soft segment promotes stronger ionic interactions and solvation capacity of ions and higher ionic conductivity in these polyurethane ionomers. The universal power law was employed to study the evolution of alternating conductivity (AC) with frequency and temperature. The calculated values of fractional exponent ranged between 0 and 1 which indicate AC conduction through hopping mechanism. Direct current conductivity evidences Arrhenius behaviour in the function of temperature and the estimated values of activation energy for poly(ethylene oxide)-rich soft segment polyurethane ionomers are found higher. The increase in the conductivity with temperature can be interpreted as a hopping mechanism assisted by chain relaxation. AFM and SAXS investigations evidence lamellar arrangement at the sub-micron scale and the nanophase-separated morphology for these polyurethane ionomers. The tensile tests evidenced that the polyurethane with highest molecular weight exhibits the highest values of mechanical properties and ductile behaviour.
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surface characterization and antimicrobial properties of Sodium Deoxycholate based poly ester ether urethane ionomer biomaterials
Reactive & Functional Polymers, 2016Co-Authors: Daniela Filip, Elena Paslaru, Cristina Gabriela Tuchilus, Doina Macocinschi, Stelian VladAbstract:Abstract New Sodium Deoxycholate-based poly(ester ether)urethane ionomers have been obtained for the development of biomedical materials. Wettability, surface tension parameters, surface morphology, roughness, water sorption and/or desorption properties, and antimicrobial efficiency were determined for the obtained polyurethane biomembranes. Contact angle analysis evidenced that the synthesized polyurethane ionomers are hydrophilic due to orientation and amount of ionic bile salt moieties towards surface. The values of interfacial tension demonstrate biocompatible qualities for these polyurethanes. SEM microphotographs show that the resulted morphologies of polyurethane ionomers are different due to the diverse polyether co-soft segments which determine the supramolecular architecture, ionic interactions between bile salt moiety and polyether segments. AFM images evidence lamellar arrangement at the sub-micron scale and the nanophase separated morphology for these polyurethanes. The estimated moisture diffusion coefficients are dependent on a range of moisture transport mechanisms in the porous membranes and the moisture content of the polyurethanes. The monolayer sorption and average pore size values were estimated by applying BET and GAB models. GAB model could not be applied in the case of high water uptake polyurethane samples. The synthesized biocidal polyurethanes are effective at inactivation of tested bacteria: Staphylococcus aureus, Sarcina lutea, Escherichia coli, except Pseudomonas aeruginosa.
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structure property relationship of Sodium Deoxycholate based poly ester ether urethane ionomers for biomedical applications
Journal of Applied Polymer Science, 2016Co-Authors: Daniela Filip, Mariana Cristea, Gabriela Lisa, Stelian Vlad, Doina Macocinschi, Mirela F. ZaltariovAbstract:New Sodium Deoxycholate based poly(ester ether)urethane ionomers were prepared for the development of biomedical materials. A structure–property relationship in the tested biomaterials was established by cross-examination of the dynamic mechanical and dielectric properties, attenuated total reflection–Fourier transform infrared investigation, thermogravimetric analysis, and surface morphology characterization. A stronger ionic interaction and solvation capacity of the ions and a higher ionic conductivity were manifested in the case of poly(ethylene oxide)-rich segments than for poly(propylene oxide)-rich segments in these polyurethane ionomers. The molecular and ionic interactions of the bile-salt moiety with different polyether cosoft segments influenced chain packing and conformation, supramolecular organization, and the resulting surface morphological microstructures of the polyurethane biomembranes. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42921.
Doina Macocinschi - One of the best experts on this subject based on the ideXlab platform.
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molecular dynamics conductivity and morphology of Sodium Deoxycholate based poly ester ether urethane ionomer biomaterials
Journal of Materials Science, 2016Co-Authors: Daniela Filip, Doina Macocinschi, Mihai Asandulesa, M Aflori, Stelian VladAbstract:Broad-band dielectric spectroscopy technique was used to investigate the molecular dynamics of new Sodium Deoxycholate-based poly(ester ether)urethane ionomers of particular interest in biomedical devices. These polyurethane ionomers have identical hard segment containing bile salt moiety but with different soft segment chemistries. Poly(ethylene oxide)-rich soft segment promotes stronger ionic interactions and solvation capacity of ions and higher ionic conductivity in these polyurethane ionomers. The universal power law was employed to study the evolution of alternating conductivity (AC) with frequency and temperature. The calculated values of fractional exponent ranged between 0 and 1 which indicate AC conduction through hopping mechanism. Direct current conductivity evidences Arrhenius behaviour in the function of temperature and the estimated values of activation energy for poly(ethylene oxide)-rich soft segment polyurethane ionomers are found higher. The increase in the conductivity with temperature can be interpreted as a hopping mechanism assisted by chain relaxation. AFM and SAXS investigations evidence lamellar arrangement at the sub-micron scale and the nanophase-separated morphology for these polyurethane ionomers. The tensile tests evidenced that the polyurethane with highest molecular weight exhibits the highest values of mechanical properties and ductile behaviour.
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surface characterization and antimicrobial properties of Sodium Deoxycholate based poly ester ether urethane ionomer biomaterials
Reactive & Functional Polymers, 2016Co-Authors: Daniela Filip, Elena Paslaru, Cristina Gabriela Tuchilus, Doina Macocinschi, Stelian VladAbstract:Abstract New Sodium Deoxycholate-based poly(ester ether)urethane ionomers have been obtained for the development of biomedical materials. Wettability, surface tension parameters, surface morphology, roughness, water sorption and/or desorption properties, and antimicrobial efficiency were determined for the obtained polyurethane biomembranes. Contact angle analysis evidenced that the synthesized polyurethane ionomers are hydrophilic due to orientation and amount of ionic bile salt moieties towards surface. The values of interfacial tension demonstrate biocompatible qualities for these polyurethanes. SEM microphotographs show that the resulted morphologies of polyurethane ionomers are different due to the diverse polyether co-soft segments which determine the supramolecular architecture, ionic interactions between bile salt moiety and polyether segments. AFM images evidence lamellar arrangement at the sub-micron scale and the nanophase separated morphology for these polyurethanes. The estimated moisture diffusion coefficients are dependent on a range of moisture transport mechanisms in the porous membranes and the moisture content of the polyurethanes. The monolayer sorption and average pore size values were estimated by applying BET and GAB models. GAB model could not be applied in the case of high water uptake polyurethane samples. The synthesized biocidal polyurethanes are effective at inactivation of tested bacteria: Staphylococcus aureus, Sarcina lutea, Escherichia coli, except Pseudomonas aeruginosa.
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structure property relationship of Sodium Deoxycholate based poly ester ether urethane ionomers for biomedical applications
Journal of Applied Polymer Science, 2016Co-Authors: Daniela Filip, Mariana Cristea, Gabriela Lisa, Stelian Vlad, Doina Macocinschi, Mirela F. ZaltariovAbstract:New Sodium Deoxycholate based poly(ester ether)urethane ionomers were prepared for the development of biomedical materials. A structure–property relationship in the tested biomaterials was established by cross-examination of the dynamic mechanical and dielectric properties, attenuated total reflection–Fourier transform infrared investigation, thermogravimetric analysis, and surface morphology characterization. A stronger ionic interaction and solvation capacity of the ions and a higher ionic conductivity were manifested in the case of poly(ethylene oxide)-rich segments than for poly(propylene oxide)-rich segments in these polyurethane ionomers. The molecular and ionic interactions of the bile-salt moiety with different polyether cosoft segments influenced chain packing and conformation, supramolecular organization, and the resulting surface morphological microstructures of the polyurethane biomembranes. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42921.
Lin Wang - One of the best experts on this subject based on the ideXlab platform.
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mixed micelles formed by biological surfactant Sodium Deoxycholate and nonionic surfactants in aqueous solution
Journal of Dispersion Science and Technology, 2020Co-Authors: Lin Wang, Xia Xin, Shasha Liu, Xiaorong Cao, Dong Yuan, Xinzheng Liu, Xingwei Luo, Junyu ZhangAbstract:AbstractThe interaction between biological surfactant Sodium Deoxycholate (NaDC) and nonionic surfactants polyoxyethylene (n) nonylphenol ether (NPn) for the formation of micelles in aqueous soluti...
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effects of graphene oxide and salinity on Sodium Deoxycholate hydrogels and their applications in dye absorption
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2015Co-Authors: Lin Wang, Xia Xin, Jinglin Shen, Mengzhou Yang, Zhaohua Song, Shiling YuanAbstract:Sodium Deoxycholate/graphene oxide (NaDC/GO) composite hydrogels were prepared in varying salinity. The hydrogels were characterized in detail by phase behavior study, transmission electron microscopy (TEM) observations, scanning electron microscopy (SEM) observations, X-ray powder diffraction (XRD) mesurements, Fourier transform infrared (FT-IR) spectra and rheological measurements. It was found that the introduction of GO to NaDC hydrogel enhances the mechanical strength of the composite hydrogel. When contacted with methylene blue solution, methylene blue can be absorbed inside the gel accompanied with a swelling of the gel. On the contrary, the hydrogel forms by NaDC only dissolves in methylene blue solution, forming a homegeous solution. Further study reveals that the gelation of NaDC/GO composite gel can be accelerated by an increase in salinity. This work may open the door for a variety of applications of NaDC/GO composite hydrogels such as in biotechnology, drug delivery and sewage treatment.
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a direct comparison of the interaction of bovine serum albumin and gelatin with Sodium Deoxycholate in aqueous solutions
Journal of Molecular Liquids, 2015Co-Authors: Huaying Ren, Xia Xin, Lin Wang, Adila ZhamandingAbstract:Abstract Surface tension, fluorescence and circular dichroism (CD) methods have been used to investigate the interaction between a biological surfactant Sodium Deoxycholate (NaDC) and proteins including bovine serum albumin (BSA) and gelatin. It can be seen from the surface tension measurements that both NaDC/BSA and NaDC/gelatin systems can form complexes and the ability of NaDC/BSA to lower surface tension is more obvious than that of NaDC/gelatin. The formation of the complexes influences not only the polarity of the microenvironment of the systems but also their fluorescence spectra. The far-UV CD spectra shows that the α-helical network of BSA increases first and then decreases as the concentration of NaDC increases, while the random coil content of gelatin always increases. A model of interaction between protein and NaDC influenced by the concentration of NaDC has been brought out based on the data gained from this study.
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biodegradable multiple stimuli responsive Sodium Deoxycholate amino acids nacl mixed systems for dye delivery
RSC Advances, 2014Co-Authors: Yongjie Zhang, Xia Xin, Jinglin Shen, Weiyue Tang, Yingjie Ren, Lin WangAbstract:Supramolecular hydrogels were prepared in mixtures of the biological surfactant Sodium Deoxycholate (NaDC) and amino acids (glycine (Gly), alanine (Ala), lysine (Lys) and arginine (Arg)) in different pH buffer solutions. We characterized their performance through phase behavior observation, transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and rheological measurements. The results demonstrate that the presence of Gly and Ala can enhance the formation of the gels, whereas the addition of Lys and Arg could cause the breakage of the hydrogen bonds and weaken the formation of the gels. The formation of hydrogels with different gelling kinetics and mechanical properties or the behavior of the sol–gel transformation of the systems may be obtained by finely modulating pH. Moreover, the addition of the halide salts (NaCl) can enhance the mechanical strength of the gels. Because of their unique responsiveness to multi-stimuli environments, these biodegradable and pH-sensitive hydrogels hold great promise as versatile vehicles for dye (or drug) delivery.
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studies on the gel behavior and luminescence properties of biological surfactant Sodium Deoxycholate rare earth salts mixed systems
Journal of Colloid and Interface Science, 2014Co-Authors: Yitong Wang, Xia Xin, Lin Wang, Chunyu Jia, Jinglin ShenAbstract:Luminescent hydrogels were facilely designed through supramolecular self-assembly of biological surfactant (Sodium Deoxycholate, NaDC) and lanthanide salt (Eu(NO3)3). The microstructures of the hydrogels were characterized by transmission electron microscopy (TEM), high-resolution TEM (HR-TEM) and field emission scanning electron microscopy (FE-SEM), from which nanofibers and tiny particles were observed. The arrangement of the Deoxycholate and metal ions was proposed according to small-angle X-ray scattering (SAXS) and X-ray powder diffraction (XRD) measurements. Rheological measurements revealed that the mechanical strength of the hydrogels increased with increasing concentration of NaDC and Eu(NO3)3, while the maximum emission of the fluorescence of the gels appeared at a stoichiometry between Eu(NO3)3 and NaDC of 1:3. It is expected that the incorporation of luminescent lanthanide ions could impart versatile functionalities for practical applications to the hydrogels.
Isiah M Warner - One of the best experts on this subject based on the ideXlab platform.
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Sodium Deoxycholate tris based hydrogels for multipurpose solute delivery vehicles ambient release drug release and enantiopreferential release
Talanta, 2018Co-Authors: Kelsey E Mcneel, Ioan I Negulescu, Noureen Siraj, Isiah M WarnerAbstract:Herein, we report the investigation of Sodium Deoxycholate (NaDC)/TRIS-based hydrogels as delivery vehicles for a broad range of applications. Three hydrogel formulations were chosen for unique rheological behaviors that suggest a change in internal hydrogel structure with the application of a shear force. In this work, we compare solute release from sheared and non-sheared hydrogels in order to explore the effect of shear force on structure and release kinetics. It was found that the application of a shear force, in addition to changes in temperature, drug solubility, drug concentration, and hydrogel formulation each affected the amount of solute ultimately released from a hydrogel system. Moreover, the use of the inherent chirality of the hydrogel network for enantio-preferential drug release was also explored. We show significant enantio-preference in the release of model drugs tryptophan and ibuprofen from the hydrogel network. Furthermore, hydrophobic domains within the hydrogel network were exploited to enable ibuprofen loading at ten times the maximum water solubility. Retention of enantio-preference was observed at this higher ibuprofen concentration. Cyclodextrin modification to the hydrogel matrix allowed for enantio-preferential inversion which is an unprecedented observation.
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Sodium Deoxycholate hydrogels effects of modifications on gelation drug release and nanotemplating
Journal of Physical Chemistry B, 2015Co-Authors: Kelsey E Mcneel, Susmita Das, Ioan I Negulescu, Noureen Siraj, Isiah M WarnerAbstract:In the present study, Sodium Deoxycholate (NaDC) was used to produce gelation of tris(hydroxymethyl)amino-methane (TRIS) solutions above, below, and near the pKa of NaDC, respectively, which yielded a neutral gelator, a charged gelator, and a mixture of each. Impacts of ionic interactions on gel formation were studied in detail and showed that pH can be used to modify many hydrogel properties including sol–gel temperature, crystallinity, and mechanical strength. Several formulations yielded a unique rheological finding of two stable regions of elastic modulus. The release of a small molecule has been investigated under different hydrogel conditions and at variable shear rate, suggesting utility as a drug-delivery vehicle. It was also observed that pH modification of the hydrogels affected nanoparticle formation. Nanoparticles derived from a Group of Uniform Materials Based on Organic Salts (nanoGUMBOS), specifically cyanine-based NIR dyes, were templated within the hydrogel network for potential applicati...
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Sodium Deoxycholate hydrogels effects of modifications on gelation drug release and nanotemplating b
The Journal of Physical Chemistry, 2015Co-Authors: Kelsey E Mcneel, Susmita Das, Ioan I Negulescu, Noureen Siraj, Isiah M WarnerAbstract:In the present study, Sodium Deoxycholate (NaDC) was used to produce gelation of tris(hydroxymethyl)amino-methane (TRIS) solutions above, below, and near the pKₐ of NaDC, respectively, which yielded a neutral gelator, a charged gelator, and a mixture of each. Impacts of ionic interactions on gel formation were studied in detail and showed that pH can be used to modify many hydrogel properties including sol–gel temperature, crystallinity, and mechanical strength. Several formulations yielded a unique rheological finding of two stable regions of elastic modulus. The release of a small molecule has been investigated under different hydrogel conditions and at variable shear rate, suggesting utility as a drug-delivery vehicle. It was also observed that pH modification of the hydrogels affected nanoparticle formation. Nanoparticles derived from a Group of Uniform Materials Based on Organic Salts (nanoGUMBOS), specifically cyanine-based NIR dyes, were templated within the hydrogel network for potential applications in tissue imaging. These nanoGUMBOS were found to be size-tunable, although material-dependent. Further understanding of NaDC/TRIS gelation has broadened the tunability and multidimensional applications of these tailored hydrogel systems.
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tunable size and spectral properties of fluorescent nanogumbos in modified Sodium Deoxycholate hydrogels
Langmuir, 2012Co-Authors: Susmita Das, Sergio L De Rooy, Atiya N Jordan, Lin Chandler, Ioan I Negulescu, Bilal Elzahab, Isiah M WarnerAbstract:Microstructures of Sodium Deoxycholate hydrogels were altered considerably in the presence of variable tris(hydroxymethyl)aminomethane (TRIS) concentrations. These observations were confirmed by use of X-ray diffraction, polarized optical microscopy, rheology, and differential scanning calorimetry measurements. Our studies reveal enhanced gel crystallinity and rigidity with increasing TRIS concentrations. The tunable hydrogel microstructures obtained under various conditions have been successfully utilized as templates to synthesize cyanine-based fluorescent nanoGUMBOS (nanoparticles from a group of uniform materials based on organic salts). A systematic variation in size (70-200 nm), with relatively low polydispersity and tunable spectral properties of [HMT][AOT] nanoGUMBOS, was achieved by use of these modified hydrogels. The gel microstructures are observed to direct the size as well as molecular self-assembly of the nanomaterials, thereby tuning their spectral properties. These modified hydrogels were also found to possess other interesting properties such as variable morphologies ranging from fibrous to spherulitic, variable degrees of crystallinity, rigidity, optical activity, and release profiles which can be exploited for a multitude of applications. Hence, this study demonstrates a novel method for modification of Sodium Deoxycholate hydrogels, their applications as templates for nanomaterials synthesis, as well as their potential applications in biotechnology and drug delivery.