Physicochemical characterisation of degrading polycaprolactone scaffolds

Abstract

a b s t r a c tA degradation study investigating the hydrolysis of different scaffolds of polycaprolactone suspended in phosphate buffer solution at 37 C was performed over a three month period. Structures included electrospun fibres, held as 2D mats and 3D bundles, and solvent cast films. These structures and their surrounding solutions were physiochemically characterised using a range of techniques. Changes in scaffold physicochemical properties were observed over the course of the study, including significant loss in molecular mass, increases in thermal properties and crystallinity, and increases in tensile properties. The presence of degradation products, such as capronic acid containing compounds was also identified in the surrounding solution. 3D electrospun bundles -as a consequence of being the least crystalline scaffold and hence most susceptible to hydrolysis e demonstrated greatest reduction in molecular mass over the three months, followed by 2D electrospun mats, and the lowest mass loss was observed for solvent cast films.

Magnetically stimulated ciprofloxacin release from polymeric microspheres entrapping iron oxide nanoparticles

“…CIP and PCL are both hydrophobic in nature and could interact among PCL chains chemically, as previously described. 44 Therefore, this could be the reason why the percentages of drug release observed in the present study did not reach 100%, as CIP (hydrophobic drug) was trapped in a PCL (hydrophobic polymer) matrix that did not degrade over 19 days in the present study.…”

“…43 Bosworth and Downes studied in vitro degradation behavior of the PCL fibers in PBS at 37°C at pH 7.4. 44 Their findings from high-performance liquid chromatography analysis revealed that PCL became more hydrophobic and, hence, is more likely to comprise longer length chains. A slight increase in the degradation by-products (no significant difference over 90 days) was detected, however, and may have been accelerated by autocatalysis occurring secondary to the accumulation of acidic breakdown products.…”

A new insight into in vitro behaviour of poly(ε-caprolactone)/bioactive glass composites in biologically related fluids

“…Young's modulus of PCL film increased gradually during incubation, while all composite films showed reduction in E t . Increase in stiffness of PCL film can be attributed to an increase in degree of crystallinity [30,31]. In the case of A2-PCL composites, the biggest changes in E t were noted in the first 3 months, and then, the values stayed on similar level until the end of the test.…”

“…The hydrolysis of polymer chains increases possibility of recrystallization by reducing their length and increasing mobility. Furthermore, because of low glass transition temperature of PCL (-60°C) mobility of non-degraded chains at 37°C during incubation in aqueous media could be enhanced and solvent-induced crystallization might have occurred [8,[28][29][30]. Although the crystallinity of PCL film increased, the mass loss was not observed, indicating bulk degradation kinetics.…”

Hydrolytic and enzymatic degradation of a poly(ε-caprolactone) network

“…Enzymatic degradation studies [26,27] show that erosion occurs at the material surface without depending on hydrophilicity. This is consistent with the fact that hydrophilicity does not change with degradation (Fig 1b).…”