Design, synthesis, characterization, and cytotoxicity of PCL/PLGA scaffolds through plasma treatment in the presence of pyrrole for possible use in urethral tissue engineering

Abstract

Electrospinning has proven to be a suitable technique for the production of small diameter tubes, with diverse applications, in the field of tissue engineering. In this work, tubular scaffolds were prepared by electrospinning a polycaprolactone/polylactic-co-glycolic acid (PLGA) blend and then treated with polypyrrole plasma for a possible application with urethral tissue. Scanning electron microscopy micrographs showed that for 10% and 20% of the PLGA in the blend, the microfibers, of varying diameters, were free of defects. The elastic modulus of the tubular scaffolds was highest (19 MPa) at 30% of PLGA, while the strain to break was maximum at 10-20% PLGA. However, at 30% of PLGA, within the polycaprolactone, the mechanical synergy (strain at break) was lost. Epithelial cells and smooth muscle cells' viability on 80/20 blends was high. When this scaffold was treated for 15 min with polypyrrol plasma, an improvement in cell viability was observed, with few polypyrrol particles being deposited and little scaffold degradation. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy showed the presence of NH, C-N, and CN groups as the chemical groups responsible of this behavior. Therefore, these scaffolds with the polypyrrole surface treatment can be used in the urethra tissue engineering.

In Vitro and In Vivo Evaluation of a Polycaprolactone (PCL)/Polylactic-Co-Glycolic Acid (PLGA) (80:20) Scaffold for Improved Treatment of Chondral (Cartilage) Injuries

“…Caixia Peng et al [ 42 ] made scaffolds of PCL/PLGA in different proportions (1:90, 50:50, 90:10) reporting good degradation properties, surface characteristics, and cellular activities, demonstrating that the PCL/PLGA (50:50) possessed potential in tissue engineering. These concentrations are very similar to those described by Sanchez-Pech [ 31 ] that, demonstrated that scaffolds made by electrospinning of PCL and PLGA (70:30) were not toxic, and the pore sizes and distances between fibers allowed the migration and proliferation of urethral cells, concluding that the mixture with these percentages is recommended for urethral tissue engineering, as it facilitates the turnover of nutrients and oxygen, an important characteristics for proper tissue repair and regeneration. The evaluation of the PCL/PLGA (80:20) scaffold by SEM ( Figure 6 ) shows results that fully agree with what was previously reported by Sanchez-Pech [ 31 ] regarding the pore size and diameter of the fibers.…”

“…The sensitivity to the ratio of both polymers can be explained by the fact that during scaffold processing by electrospinning, the morphology of the PLGA/PCL fibers is affected by the percentage of the components. In this sense, it has been described that increasing the amount of PLGA modifies the average diameter of the fibers and their distribution; for example, Sanchez-Pech et al, in2020 reported a reduction in fiber diameter starting at added 10% 20%, and 30% of PLGA in the PCL matrix and pore size decreases when the PLGA content increases [ 31 ].…”

“…The proportion PCL/PLGA 80:20 has been analyzed in vascular grafts [22], in drug release [23,24], in nerve regeneration [25,26], for skin and osteogenic engineering [27][28][29], and for its general characteristics in tissue engineering [30]. In addition, changes in the diameter and morphology of the fibers as a function of the content of PLGA, as well as different mechanical properties, have been reported by our group [31]. In this work, we probed a PCL/PLGA (80:20) scaffold in combination with cells as an option for tissue engineering of articular hyaline cartilage.…”

Effect of different exposure times on physicochemical, mechanical and biological properties of PGS scaffolds treated with plasma of iodine-doped polypyrrole

“…They concluded that the PCL/PLGA scaffolds treated with PPy plasma for 25 and 30 minutes exhibited cytotoxicity when compared with scaffolds treated for 15 minutes. 52…”

Tissue engineering in reconstructive urology—The current status and critical insights to set future directions-critical review

“…It is especially important for the regeneration of multilayer hierarchically organized structures, such as the urinary tract wall, as this parallel spatial architecture allows the regenerating tissue to maintain its orientation. Moreover, electrospinning allowed for the creation of small-diameter tubes with high uniaxial mechanical resistance appropriate for urethral surgery, as demonstrated by Sánchez-Pech et al (2019) The significant advantage of their work is that it includes extensive biomechanical analysis, which is usually only provided marginally. Composite tubular scaffolds created from PCL and PLGA exhibited a high elastic modulus (19 MPa), ideal to withstand bursting pressure within the human urethra.…”