Influence of dissolution processing of PVA blends on the characteristics of their hydrogels synthesized by radiation—Part I: Gel fraction, swelling, and mechanical properties

Alcantara, Mara T.S.; Brant, A.J.C.; Giannini, D.R.; Pessoa, João; Andrade, Alexandre B.; Riella, Humberto Gracher; Lugão, Ademar B.

doi:10.1016/j.radphyschem.2012.01.048

Cited by 35 publications

(11 citation statements)

References 14 publications

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“…However, in association with the density (Y 2 ), a larger effect from the X 1 and X 2 effects can be verified (Table IV), which may be justified by the modification of the number of hydrogen bonds between PVA chains and also by the presence of reticulations with STMP, as demonstrated in Figure 8. 23,24,27 Regarding dynamic viscosity (Y 3 ), Table V revealed a greater effect of X 1 , confirming the data observed during the initial analysis of the obtained results. However, Y 4 is directly affected by the initial pH of the reaction, as expected, once there is consumption of hydroxide ions during the reaction supplied by NaOH and utilized for the pH adjustment, as demonstrated in Table VI. These results can be observed by the analysis of Figure 2, wherein the effect of each variable can be observed with a confidence level of 95%.…”

Section: Discussionsupporting

confidence: 83%

“…This finding can be explained by the increase of hydrogen bonds between the PVA chains, favoring the increase of the material viscosity. 23,24 To conduct a detailed study concerning the behavior of Y 1 , Y 2 , Y 3 , and Y 4 , considering the variation of PVA concentration (X 1 ), the PVA/STMP ratio (wt/wt) (X 2 ), and initial pH (X 3 ) as well as the optimization of the results to obtain a hydrogel with vitreous humor characteristic, a statistical study was conducted considering all the obtained data. Thus, the validation of the utilized model was verified during the analysis of the results ( Figure 1 and Tables (III-VI)).…”

Section: Discussionmentioning

confidence: 99%

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Conditions for obtaining polyvinyl alcohol/trisodium trimetaphosphate hydrogels as vitreous humor substitute

et al. 2015

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Hydrogels are polymeric materials with numerous medical and biological applications because of their physicochemical properties. In this context, the conditions were defined for obtaining a hydrogel with characteristics similar to the vitreous humor using polyvinyl alcohol (PVA) and trisodium trimetaphosphate (STMP). The concentration of PVA (X1 ), PVA/STMP ratio (X2 ), and initial pH (X3 ) were modified, and their effect was analyzed in terms of the refractive index (Y1 ), density (Y2 ), dynamic viscosity (Y3 ), and final pH (Y4 ). The results demonstrated that X1 interferes with Y1 , Y2 , and Y3 , and X2 interferes with Y2 and Y3 . The best condition for obtaining a hydrogel with characteristics similar to the vitreous humor was 4.2586% PVA (wt/wt), STMP/PVA ratio of 1:6.8213 (wt/wt), and initial pH of 9.424. DSC, ATR-FTIR, swelling degree, and AFM analysis confirmed the PVA reticulation with STMP. Furthermore, STMP increased the glass transition temperature and decreased the water uptake of ∼50% of the hydrogels, which can be explained by the crosslinking of PVA chains. Infrared spectroscopy revealed a decrease of hydroxyl bonds and confirmed the reticulation between PVA and STMP. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1386-1395, 2016.

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Section: Discussionsupporting

confidence: 83%

Section: Discussionmentioning

confidence: 99%

Conditions for obtaining polyvinyl alcohol/trisodium trimetaphosphate hydrogels as vitreous humor substitute

et al. 2015

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“…In theory, gel shrinkage will result in denser polymeric networks leading to hardening of the test specimen. In addition, as demonstrated by Alcantâra et al, of PVA gels were lower for samples of higher cross-linking density independent of the preparation technique and the gel composition used [41]. The complexity of cardiac tissue or human vessel wall components regarding mechanical properties has been reported by Bank et al, [42].…”

Section: Long-term Stabilitymentioning

confidence: 81%

Long-term stable hydrogels for biorelevant dissolution testing of drug-eluting stents

Semmling¹,

Nagel²,

Sternberg³

et al. 2013

J Pharm Technol Drug Res

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Background: For the purpose of biorelevant dissolution testing hydrogels have recently been used to investigate release and distribution behavior of drugs released from specialized dosage forms such as drug-eluting stents. For stent testing using the vesselsimulating flow-through cell (vFTC) certain functional properties regarding life time of the used hydrogels such as hardening/ softening, degradation/erosion and swelling/shrinkage during the time period of dissolution testing are of highest interest. Methods: Hydrogels composed of alginate, agar, agarose, polyacrylamide (PAA) and poly(vinyl alcohol) (PVA) were prepared using physical and chemical cross-linking methods. To characterize the mechanical stability of the test specimens stress-strain curves were recorded by texture analysis before and after perfusion in the vFTC for 28 days and Young's moduli were calculated. The surface morphology of the test specimens was examined using scanning electron microscopy. Water uptake upon incubation was determined. Results: Besides the previously established alginate gels, suitable hydrogels consisting of 2 wt% agar, 2 wt% agarose, 10 wt% PAA or 15 wt% PVA were identified. Comparison of stress-strain curves indicated a sample softening of reference as well as agar and a slight hardening of PVA whereas hardness of agarose and PAA remained unchanged. Young's moduli of agarose and PAA were almost unaffected after 28 days of perfusion. Swelling of PAA by 18 wt% and shrinkage of PVA by 14 wt% was observed compared to agar and agarose whose water uptake was negligibly small. Conclusion:The hydrogels differ not only in their preparation procedure but also regarding their swelling properties, surface morphology and texture. Due to the ease of handling, mild gelling conditions, no swelling tendencies, elastic properties, and nearly unaffected texture after 28 days of perfusion compared to native test specimens, agarose gels are considered as the best choice for longterm testing using the vFTC.

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“…The W S is the samples' weight at each interval time. Whereas, W D is the dry weight prior to swelling test and W DS is the dry weight after swelling [25][26][27].…”

Section: In Vitro Analysismentioning

confidence: 99%

In vitro evaluation of PVA gels loaded with Copaiba Oil and Duotrill®

et al. 2019

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Enrofloxacin can be slowly delivered through polymeric systems and the addition of oil could increase the polymeric gels hydrophobicity and help the continuous release. The present work intended to develop and characterize microstructurally (XRD and FTIR) and in vitro (swelling and antimicrobial tests) the PVA hydrogels loaded with copaiba oil and Duotrill (enrofloxacin) to treat bacterial infections, as pyelonephritis, in the veterinary field. Duotrill  and oil combined diminished the gels degree of crystallinity and it was observed interaction between phases due to a new band found only in PVA hydrogels loaded with copaiba oil and Duotrill (PVA-DO) FTIR spectrum. The samples with oil swelled less than samples without it, where copaiba oil altered the samples' hydrophilicity. PVA-DO presented lower weight loss and higher gel fraction than PVA, indicating the loaded material increased the gels stability. All samples containing oil and Duotrill  inhibited S. aureus.

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Influence of dissolution processing of PVA blends on the characteristics of their hydrogels synthesized by radiation—Part I: Gel fraction, swelling, and mechanical properties

Cited by 35 publications

References 14 publications

Conditions for obtaining polyvinyl alcohol/trisodium trimetaphosphate hydrogels as vitreous humor substitute

Conditions for obtaining polyvinyl alcohol/trisodium trimetaphosphate hydrogels as vitreous humor substitute

Long-term stable hydrogels for biorelevant dissolution testing of drug-eluting stents

In vitro evaluation of PVA gels loaded with Copaiba Oil and Duotrill®

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