Characterization in respect to degradation of titanium‐coated polypropylene surgical mesh explanted from humans

Abstract

Titanium-coated polypropylene (Ti-PP) mesh was introduced in 2002 as a surgical mesh for the treatment of hernias and shortly after for pelvic floor surgery, with the aim of improving biocompatibility when compared to non-titanised/regular PP mesh implants. The application of a titanium coating could also be beneficial to address concerns regarding the exposure of PP in an in vivo environment. Many studies have shown that PP, although it is widely accepted as a stable polymer, is subject to oxidation and degradation, such degradation affects the mechanical behavior, that is, the stiffness and tensile strength of PP mesh. Despite the wide clinical use of Ti-PP surgical meshes, no study has yet investigated the residual material properties post clinical deployment and subsequent explantation. In this study, two explanted Ti-PP mesh samples each having different incorporation durations from two patients were examined. Material analysis conducted within this study includes the following techniques: attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, low voltagescanning electron microscopy (LV-SEM), backscattered electron (BSE) imaging, energy dispersive X-ray spectroscopy (EDS) and secondary election hyperspectral imaging (SEHI). The hypothesis of this study is that the Ti coating successfully shields the PP mesh from oxidative stress in vivo and thus protects it from degradation. The results of this analysis show for the first time evidence of bulk oxidation, surface degradation, and environmental stress cracking on explanted Ti-PP meshes.

Development of PCL PolyHIPE Substrates for 3D Breast Cancer Cell Culture

“…To avoid surface charging and damage to the sample, a low accelerating voltage of 1 kV with typical vacuum pressure of 10 −5 mbar at a working distance of 3 mm was applied. Working with low acceleration voltage allows for accurate visualisation of pore size and morphology of non-conductive materials such as the PCL polyHIPE substrates without the need of a metal coating [36]. An Everhart-Thornley detector (ETD) was used for low magnification images and a through lens detector (TLD) was used for high magnification images.…”

Carbon Nanotubes Facilitate Silk Hierarchical Assembly by Dry Drawing

“…Notably the cast film is over 10 μm thick and does not affect interfacial layer analysis. SEHI which allows for chemical mapping, [34][35][36] was also applied to confirm the presence of sp 2 carbon for the CNTs and notably highlighted a heterogeneous distribution of chemical bonding in this CNT interfacial layer. SEHI identified chemical bonding variations in SE ranges which have previously been associated with ordered protein structures [37] and S-S (disulfide) bonding.…”

Characterization and quantification of oxidative stress induced particle debris from polypropylene surgical mesh

“…One possible explanation for the results shown in Figure 5 is that the PP particles have experienced a loss of C‐C coupling, resulting in greater absorption from side‐group mode r(CH 3 ), which previous studies have linked with a decrease in the degree of PP crystallinity. [ 40,47–48 ] As greater C‐H bonding has been assigned to shorter chains in helical conformation, [ 47,49 ] this result could therefore indicate the resulting shed PP particles experience variations in crystallinity. Previous studies have proposed a mechanism by which molecular chain scission would favor the less crystalline regions, resulting in the formation of crystalline surface particles.…”

“…Previous studies have proposed a mechanism by which molecular chain scission would favor the less crystalline regions, resulting in the formation of crystalline surface particles. [ 40 ]…”

“…Previous studies have proposed a mechanism by which molecular chain scission would favor the less crystalline regions, resulting in the formation of crystalline surface particles. [40] To understand if the variations in surface chemistry observed on the nano-scale in Figure 5 had any effect on the bulk chemistry or mechanical properties of the PP mesh samples, both Fourier transform infrared spectroscopy (ATR-FTIR) and uniaxial tensile testing was performed and presented in Figure 6. ATR-FTIR is a recommended technique for determining the chemical structure of synthetic polymers used in medical devices in accordance with the guidelines of the ISO 10993-18:2O20 standard.…”