In the quest to repair articular cartilage (AC) defects, electrospun nanofibers have emerged as a promising material, but their mechanical properties have lagged behind those of natural tissue. A recent study, published in the journal *Nano Select* (translated as “Nano Choice”), has shed new light on the friction and wear characteristics of these materials, potentially paving the way for improved cartilage engineering and broader applications in the energy sector.
André Mathias Souza Plath, a researcher at the Institute for Biomechanics at ETH Zurich in Switzerland, led the study that aimed to evaluate the coefficient of friction (COF) and wear in electrospun mats using a universal testing tribometer. “There are no standard protocols to test friction in electrospun materials,” Plath explained. “Only a few studies have reported the COF of electrospun mats, so our work seeks to address this gap.”
The research team tested poly(ε-caprolactone) (PCL) mats against stainless steel, polyoxymethylene (POM), and rubber balls. They found a statistically significant difference between metal and rubber/plastic counterparts, attributing this to surface chemistry. When POM countersurfaces were rubbed at varying speeds of 1, 10, and 50 millimeters per second, the results showed a small reduction in COF proportional to speed, along with stick-and-slip behavior.
One of the most intriguing findings was the significant reduction in COF when the team tested a PCL-zein-based material. The water contact angle of this material decreased from 120° to 60°, demonstrating a 20% reduction in COF due to lubrication efficiency and a 33% reduction due to hydrophobic-hydrophilic contacts. “This study successfully evaluates the tribological properties of electrospun mats,” Plath noted, “and opens up new perspectives on shear and friction biostimulation in electrospun surfaces.”
The implications of this research extend beyond cartilage engineering. In the energy sector, understanding and controlling friction and wear in materials can lead to more efficient and durable components. For instance, improving the tribological properties of materials used in wind turbines or hydraulic systems could enhance their performance and longevity, reducing maintenance costs and downtime.
Plath’s work also highlights the importance of developing standard protocols for testing friction in electrospun materials. As the field of nanotechnology continues to advance, such protocols will be crucial for ensuring the reliability and reproducibility of research findings.
The study’s findings not only advance our understanding of electrospun nanofibers but also underscore the potential for these materials to revolutionize various industries. As Plath and his team continue to explore the tribological properties of electrospun mats, their work could pave the way for innovative solutions in cartilage repair and beyond.