Fabrication of Forcespinning® nanofibers incorporating nopal extract

Abstract

In this study, nanofibers composed of Opuntia cochenillifera nopal mucilage (N) extract combined with chitosan (CH) and pullulan (PL) (N/CH/PL) were produced via Forcespinning®. The developed nonwoven composite membranes are composed of long, continuous and homogeneous fibers with average fiber diameter varying between 251 ± 77 nm and 406 ± 127 nm depending on the concentration of N. After crosslinking, the developed membranes were highly stable in water. The water absorption capacity of the N/CH/PL composite nanofiber membranes was shown to be 65% higher compared to CH/PL nanofiber membranes. Nopal dip-coated membranes show inhibition of Gram-negative Escherichia coli, indicating antibacterial properties. These findings suggest that the incorporation of naturally derived nopal extract into nanofiber systems could provide a natural alternative for dressings used in wound healing applications.

Cell proliferative properties of Forcespinning®nopal composite nanofibers

“…Nanofiber matrices may mimic the ECM, presenting similar structural characteristics for cell migration and alignment. N extract composite nanofibers have an average fiber diameter of ~300-406 nm, 31 where a consistent characteristic to the ECM was demonstrated with their appearance via confocal microscopy (Figure 2). At a 2-and 4-days incubation, cell adhesion and proliferation appear to be constant with no significant difference (p > 0.05), as determined by the quantitative cell count method (Figure 4).…”

“…38 observed to have a higher interaction within N100 composite nanofibers, as shown anchoring through an overlapping cell presence at different depths of the nanofibrous membrane (Figure 5(d)). This can be seen through a Resazurin cell viability test, 31 where a higher metabolic activity was shown due to cells adhering onto and migrating within N100 composite nanofibers, as described in a previous study where a nanofiber structure sustains the viability of migrating cells. 34 Our results suggest that after 14 days, cell adhesion and proliferation are consistent with a favorable environment in N100 composite nanofibers (see Z-stack reconstruction (Figure 6).…”

“…The smalldiameter pore size in the binary nanofiber matrix may reduce cell migration due to a lack of penetration, 1 as previously reported through SEM micrographs of these samples. 31,35 In contrast, the N50, N100, and DN100 nanofibers presented an elongated cell morphology as shown through MTR signaling. In a separate assessment for cell morphology, SEM micrographs of 3T3 cells were shown after a 6 days incubation period (Figure 3 Engineered materials can support cell growth onto fiber diameters around < 400 nm, promoting differentiation and beneficiary gene expression depending on the cell line, allowing the nanofibers to resemble the ECM.…”

“…Binary chitosan/pullulan (CH/PL) nanofibers were produced and combined with varying amounts of N extract: solvent preparations with N extract and DI water, at varying volume/volume ratios, were combined with CH/PL to produce composite fibers N1/CH/PL (N1), N50/CH/PL (N50), and N100/CH/PL (N100) as previously described. 31…”

“…[28][29][30] Previously, we developed chitosan (CH) and pullulan (PL) nanofibers incorporating varying concentrations of O. cochenillifera "nopal" mucilage (N) extract with antibacterial properties. 31 Here, we explore the ability of N/ CH/PL composite nanofibers to support cell adhesion and proliferation compared to control CH/PL composite nanofibers lacking N extract. Our data suggest that the incorporation of plant-based bioactive compounds may provide a nanofiber-based strategy for improved wound healing applications.…”