Tissue Engineering And Nanotheranostics

(Steven Felgate) #1

“9.61x6.69” b2815 Tissue Engineering and Nanotheranostics


Characterization of Biomaterial Patches as Fetal Surgery Implants 43

displayed by explanted specimens, in comparison with 166°C for pris-


tine specimens, and five of the 14 specimens had statistically signifi-


cant Tm values (Fig. 9). A shift is observed in the peak temperature,


from 458°C for pristine specimens to approximately 465°C for


explanted meshes. The author hints at the possibility of in vivo oxida-


tion of PP, based on SEM, DSC and TGA results. The broader melt-


ing peak in DSC was attributed to increased polydispersity of the


material, but no gel permeation chromatography analysis was per-


formed to study the change in molecular weight distribution. The


author states that oxidized materials usually undergo some weight


loss, which could have been supported by gravimetric analysis.


Fig. 9. (a) SEM of the PP component of a pristine Composix E/X mesh; (b) SEM
of an explanted PP mesh with blisters on fibers; (c) DSC; (d) TGA thermograms of
explanted and pristine meshes.^21


Temperature (°C)

Deriv

. Weight (%/°C)


(a)(b)

(c)(d)

(^50) Composix E/x
Subject #2
40 Subject #9
30
20
Heat Flow Endo Up [mW]
100 200 300
Temperature [ºC]
(^400) 0.0
350 400 450 500 550
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Composix E/x
Subject #2
Subject #9

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