Morphological and biomechanical characterization of poly(glycolic acid) scaffolds after in vitro degradation

ABSTRACT A gene that codes for a novel intracellular poly(3-hydroxybutyrate) (PHB) depolymerase, designated PhaZ1, has been identified in the genome of Bacillus megaterium. A native PHB (nPHB) granule-binding assay showed that purified soluble PhaZ1 had strong affinity for nPHB granules. Turbidimetric analyses revealed that PhaZ1 could rapidly degrade nPHB granules in vitro without the need for protease pretreatment of the granules to remove surface proteins. Notably, almost all the final hydrolytic products produced from the in vitro degradation of nPHB granules by PhaZ1 were 3-hydroxybutyric acid (3HB) monomers. Unexpectedly, PhaZ1 could also hydrolyze denatured semicrystalline PHB, with the generation of 3HB monomers. The disruption of the phaZ1 gene significantly affected intracellular PHB mobilization during the PHB-degrading stage in B. megaterium, as demonstrated by transmission electron microscopy and the measurement of the PHB content. These results indicate that PhaZ1 is functional in intracellular PHB mobilization in vivo. Some of these features, which are in striking contrast with those of other known nPHB granule-degrading PhaZs, may provide an advantage for B. megaterium PhaZ1 in fermentative production of the biotechnologically valuable chiral compound (R)-3HB.

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Porous and dense poly(L-lactic acid) and poly(D,L-lactic acid-co-glycolic acid) scaffolds: In vitro degradation in culture medium and osteoblasts culture

Journal of Materials Science Materials in Medicine ◽

10.1007/s10856-004-5740-6 ◽

2004 ◽

Vol 15 (12) ◽

pp. 1315-1321 ◽

Cited By ~ 51

Author(s):

S. H. Barbanti ◽

A. R. Santos ◽

C. A. C. Zavaglia ◽

E. A. R. Duek

Keyword(s):

Lactic Acid ◽

Glycolic Acid ◽

Culture Medium ◽

In Vitro Degradation

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In Vitro Corrosion Behavior of Biodegradable Iron Foams with Polymeric Coating

Materials ◽

10.3390/ma13010184 ◽

2020 ◽

Vol 13 (1) ◽

pp. 184 ◽

Cited By ~ 3

Author(s):

Radka Gorejová ◽

Renáta Oriňaková ◽

Zuzana Orságová Králová ◽

Matej Baláž ◽

Miriam Kupková ◽

...

Keyword(s):

Corrosion Behavior ◽

Polymeric Coating ◽

Attractive Alternative ◽

In Vitro Degradation ◽

Corrosion Rates ◽

Degradation Rates ◽

Ft Ir ◽

Resorbable Implants

Research in the field of biodegradable metallic scaffolds has advanced during the last decades. Resorbable implants based on iron have become an attractive alternative to the temporary devices made of inert metals. Overcoming an insufficient corrosion rate of pure iron, though, still remains a problem. In our work, we have prepared iron foams and coated them with three different concentrations of polyethyleneimine (PEI) to increase their corrosion rates. Scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDX), Fourier-transform infrared spectroscopy (FT-IR), and Raman spectroscopy were used for characterization of the polymer coating. The corrosion behavior of the powder-metallurgically prepared samples was evaluated electrochemically using an anodic polarization method. A 12 weeks long in vitro degradation study in Hanks’ solution at 37 °C was also performed. Surface morphology, corrosion behavior, and degradation rates of the open-cell foams were studied and discussed. The use of PEI coating led to an increase in the corrosion rates of the cellular material. The sample with the highest concentration of PEI film showed the most rapid corrosion in the environment of simulated body fluids.

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