Preparation and microstructure of cobalt(III) poly  (acrylate) hybrid materials

Álvarez-Gayosso, Carlos; Canseco, M. A.; Estrada, Renz John R.; Palacios‐Alquisira, Joaquín; Hinojosa, Jaime; Castaño, V. M.

doi:10.14419/ijbas.v4i3.4172

Cited by 18 publications

(8 citation statements)

References 17 publications

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“…Moreover, in the spectrum of formulation F2 in Figure 6a, a band at 1624 cm −1 appeared, and simultaneously, the intensive band at 1697 cm −1 assigned to the PA carboxyl group was not present. This observation was similar to results in our previous work [29] and the study of Alvarez-Gayosso et al [30]. The vibrations at approximately 1700 cm −1 belonging to the -COOH group could decrease in intensity upon the appearance of the maximum in the range of 1650 to 1500 cm −1 attributed to COO − stretching.…”

Section: Ftir Spectroscopysupporting

confidence: 93%

“…It should be mentioned that in the spectrum of F3, the wide band at 1631 cm −1 was observed and was difficult to explicitly assign to any of the F3 components. According to the investigation of Alvarez-Gayosso et al [30], vibration bands assigned to carboxylic acid, -COOH, appear at approximately 1700 cm −1 , although the carboxylate ion -COO − vibrations are located in the range from 1650 to 1500 cm −1 . This observation indicates an interaction between the PVP carbonyl group and APN carboxylate group.…”

Section: The Existence Of Hydrogen Bonds Between Two Carboxyl Groups mentioning

confidence: 99%

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Bipolymeric Pectin Millibeads Doped with Functional Polymers as Matrices for the Controlled and Targeted Release of Mesalazine

2020

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Targeted drug delivery systems are a very convenient method of treating inflammatory bowel disease. The properties of pectin make this biopolymer a suitable drug carrier. These properties allow pectin to overcome the diverse environment of the digestive tract and deliver the drug to the large intestine. This investigation proposed bipolymeric formulations consisting of the natural polymer pectin and a synthetic polymer containing the drug 5-aminosalicylic acid. Pectin beads were prepared via ionotropic gelation involving the interaction between the hydrophilic gel and calcium ions. The obtained formulations consisted of natural polymer, 5-aminosalicylic acid (5-ASA) and one of the synthetic polymers, such as polyacrylic acid, polyvinylpyrrolidone, polyethylene glycol or aristoflex. The release of the drug was carried out employing a basket apparatus (USP 1). The acceptor fluid was pH = 7.4 buffer with added enzyme pectinase to reflect the colon environment. The amount of the released drug was determined using UV-Vis spectrophotometry at a wavelength of λ = 330 nm. The kinetics of the drug dissolution revealed that none of the employed models was appropriate to describe the release process. A kinetic analysis of the release profile during two release stages was carried out. The fastest drug release occurred during the first stage from a formulation containing pectin and polyethylene glycol. However, according to the applied kinetic models, the dissolution of 5-ASA was rather high in the formulation without the synthetic polymer during the second stage. Depending on the formulation, 68–77% of 5-ASA was released in an 8-hour time period. The FTIR and DSC results showed that there was no interaction between the drug and the polymers, but interactions between pectin and synthetic polymers were found.

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Section: Ftir Spectroscopysupporting

confidence: 93%

Section: The Existence Of Hydrogen Bonds Between Two Carboxyl Groups mentioning

confidence: 99%

Bipolymeric Pectin Millibeads Doped with Functional Polymers as Matrices for the Controlled and Targeted Release of Mesalazine

2020

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“…Moreover, -CH bending vibrations signal was also identified at 720 cm −1 [45]. Since the pH of the solution during modification was higher than 6.4, the dissociation of COOH into COO − and H + is clearly presented in the PAA-modified membranes at ≈1550 cm −1 [46], which evidences the presence of PAA on the modified membrane surfaces. This ATR-FTIR analysis, therefore, demonstrates the high chemical stability of the polyester-based AEMs after adding a negative PAA monolayer onto their surfaces.…”

Section: Membrane Surface Characterization: Contact Angle Water Uptake Ion Exchange Capacity Fixed Charge Density Swelling and Fourier Atmentioning

confidence: 83%

Characterization of Poly(Acrylic) Acid-Modified Heterogenous Anion Exchange Membranes with Improved Monovalent Permselectivity for RED

et al. 2020

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The performance of anion-exchange membranes (AEMs) in Reverse Electrodialysis is hampered by both presence of multivalent ions and fouling phenomena, thus leading to reduced net power density. Therefore, we propose a monolayer surface modification procedure to functionalize Ralex-AEMs with poly(acrylic) acid (PAA) in order to (i) render a monovalent permselectivity, and (ii) minimize organic fouling. Membrane surface modification was carried out by putting heterogeneous AEMs in contact with a PAA-based aqueous solution for 24 h. The resulting modified membranes were firstly characterized by contact angle, water uptake, ion exchange capacity, fixed charge density, and swelling degree measurements, whereas their electrochemical responses were evaluated through cyclic voltammetry. Besides, their membrane electro-resistance was also studied via electrochemical impedance spectroscopy analyses. Finally, membrane permselectivity and fouling behavior in the presence of humic acid were evaluated through mass transport experiments using model NaCl containing solutions. The use of modified PAA-AEMs resulted in a significantly enhanced monovalent permselectivity (sulfate rejection improved by >35%) and membrane hydrophilicity (contact angle decreased by >15%) in comparison with the behavior of unmodified Ralex-AEMs, without compromising the membrane electro-resistance after modification, thus demonstrating the technical feasibility of the proposed membrane modification procedure. This study may therefore provide a feasible way for achieving an improved Reverse Electrodialysis process efficiency.

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“…The maxima at the wavenumbers of 1453 and 1413 cm −1 were assigned to the scissors and bending vibrations of CH 2 and CHCO. The signal at 1220 cm −1 was attributed to OH bending from the carboxyl group [38][39][40].…”

Section: Ftir Studymentioning

confidence: 99%

The Interactions and Release Kinetics of Sodium Hyaluronate Implemented in Nonionic and Anionic Polymeric Hydrogels, Studied by Immunoenzymatic ELISA Test

2021

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Hyaluronan is a natural polymer that was introduced to wound therapy. Formulations based on synthetic polymers such as methylcellulose (MC) and polyacrylic acid (PA) containing hyaluronan (HA) were proposed for the development of prospective wound-healing preparations. The formulations of different carrier concentrations containing a fixed amount of HA were prepared, and their viscosity was measured. The HA release was evaluated by employing the apparatus paddle over a disc. The hydrogels were introduced to the donor chamber, and HA was released to the pH = 7.4 buffer. The amount of HA released was obtained using the ELISA test. The release was analyzed on the basis of different kinetic models: zero-, first-, and second-order kinetics, as well as Higuchi and Korsmeyer–Peppas equations. The release rate constants and the half release time were calculated from these equations. According to the value of the coefficient of the determination, the best model describing the observed process was selected. The comparison between the dissolution profiles was carried out by calculating the difference factor f1 and the similarity factor f2. The interaction between the hydrogel components was investigated by Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) measurements. The study revealed that the zero-order equation best described the release of HA from the formulations studied. The FTIR research and the DSC study showed the intermolecular interaction between HA chains in MC-based compositions, as well as between HA and the synthetic polymer in the PA-based formulations. The study revealed that the formulation with a higher concentration of synthetic polymer may prolong the release of HA. The obtained results indicated that the proposed hydrogels have potential for wound healing and may accelerate skin regeneration.

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Preparation and microstructure of cobalt(III) poly (acrylate) hybrid materials

Cited by 18 publications

References 17 publications

Bipolymeric Pectin Millibeads Doped with Functional Polymers as Matrices for the Controlled and Targeted Release of Mesalazine

Bipolymeric Pectin Millibeads Doped with Functional Polymers as Matrices for the Controlled and Targeted Release of Mesalazine

Characterization of Poly(Acrylic) Acid-Modified Heterogenous Anion Exchange Membranes with Improved Monovalent Permselectivity for RED

The Interactions and Release Kinetics of Sodium Hyaluronate Implemented in Nonionic and Anionic Polymeric Hydrogels, Studied by Immunoenzymatic ELISA Test

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