Improved electrochemical performance of multi-walled carbon nanotube reinforced gelatin biopolymer for transient energy storage applications

Gelatin Multiwalled Carbon Nanotube Composite 3D Printed Semi Biological Mesh for Abdominal Hernia Treatment

Hernia is characterized by the protrusion of organs or tissue through weakened areas in the abdominal cavity wall. A common treatment for hernia involves the implantation of a mesh which promotes the growth of new tissue around or within the implanted material in the damaged area. The mesh is typically made from synthetic materials like polypropylene. However, such meshes have safety concerns like biofilm and scar tissue formation, foreign body reactions, and chronic pain. These concerns gave rise to the development of biological meshes. Owing to mechanical weakness, biological meshes fail due to migration and rapid degradation. This study is aimed to develop a mechanically viable biopolymer-based composite degradable mesh. A gelatin-MWCNT composite 3D printed mesh has been developed with different pore sizes and filament sizes. Adding MWCNTs improved the composite's ductility, printability, hydrophilicity, and modulus, and reduced its degradation rate. The 3D-printed mesh also showed signs of cell attachment and proliferation representing non-toxicity of MWCNTs within the composite materials. The data showed improved cell adherence due to the incorporation of MWCNTs within the composite materials. Among the various material compositions tested, the composite material with gelatin with 0.01 g MWCNTs gave the optimum mechanical strength and biocompatibility results.

UV-Vis quantification of the iron content in iteratively steam and HCl purified single-walled carbon nanotubes

As-produced carbon nanotubes contain impurities which can dominate the properties of the material and are thus undesired. Herein we present a multi-step purification treatment that combines the use of steam and hydrochloric acid in an iterative manner. This allows the reduction of the iron content down to 0.2 wt. % in samples of single-walled carbon nanotubes (SWCNTs). Remarkably, Raman spectroscopy analysis reveals that this purification strategy does not introduce structural defects into the SWCNTs' backbone. To complete the study, we also report on a simplified approach for the quantitative assessment of iron using UV-Vis spectroscopy. The amount of metal in SWCNTs is assessed by dissolving in HCl the residue obtained after the complete combustion of the sample. This leads to the creation of hexaaquairon(III) chloride which allows the determination of the amount of iron, from the catalyst, by UV-Vis spectroscopy. The main advantage of the proposed strategy is that it does not require the use of additional complexing agents.

The role of multi-walled carbon nanotubes in enhancing the hydrolysis and thermal stability of PLA

Polylactic acid (PLA) is a bioresorbable and biodegradable polymer extensively used in various biomedical and engineering applications. In this study, we investigated the mass loss and thermal properties of PLA-multi-walled carbon nanotube (MWCNT) composites under simulated physiological conditions. The composites were prepared by melting PLA with 0.1, 0.5, 1.0, and 5.0 wt% MWCNTs using an ultrasonic agitator, and FTIR analysis confirmed composite formation. Subsequently, the composites were subjected to hydrolysis under simulated physiological conditions (pH 7.4 and 37 °C) for up to 60 days. The results revealed that the mass loss of the composites decreased with increasing MWCNT content, suggesting that the presence of MWCNTs decelerated the hydrolysis process. On day 58, the mass loss of pure PLA was 12.5%, decreasing to 8.34% with 0.1% MWCNT, 5.94% with 0.5% MWCNT, 4.59% with 1% MWCNT, and 3.54% with 5.0% MWCNT. This study offers valuable insights into the behavior of PLA-MWCNT composites under physiologically simulated conditions, facilitating the development of new polymer composites with enhanced thermal stability and degradation resistance for biomedical applications.