Fabrication of novel rosin-based antibacterial nanofibers for particulate matter removal

In this study, sustainable, biodegradable and eco-friendly filters were prepared via electrospinning technique to obtain fibrous membranes for the filtration of particulate matter (PM _2.5 and PM ₁₀ ) and bacteria removal. For this purpose, natural rosin (R), and modified rosin (MR, pentaerythritol ester rosin) were selected, due to the antibacterial properties and polylactic acid (PLA) was used as a bio-based plasticizing agent to facilitate the fibers formation from rosin samples. Effects of the process parameters such as concentration of the solution, ratio of the polymers, spinning volume of the membranes, voltage and flow rate, on the fiber formation were studied through Scanning Electron Microscope (SEM) analysis. Under the optimum condition, 40% modified rosin/PLA was selected for fabrication of filters and further analysis. The filtering efficiency was assessed in a real-scale room by measuring the penetration of neutralized aerosol particles (2% NaCl) through selected electrospun filters. The filtration capacity of fibrous membranes prepared with 40% modified rosin/PLA was 97.00% for PM _2.5 and 97.9% for PM ₁₀ . On the other hand, fibrous membranes with 10% PLA, fabricated as a control sample, demonstrated a filtration efficiency of 99.00% for PM _2.5 and 99.2% for PM ₁₀ . Moreover, antibacterial analysis results revealed that PLA-based filters showed no activity against Staphylococcus aureus, Escherichia coli, Bacillus cereus, and Staphylococcus epidermidis . However, filters prepared with 40% modified rosin/PLA inhibited these bacteria and formed inhibition zones of 9.50±0.50, 8.50±0.50, and 9.83±1.04, effectively preventing bacterial growth. In summary, although the filtration efficiency of fibrous membranes prepared with 40% MR/PLA fibers is slightly lower compared to those with 10% PLA, their strong antibacterial activities highlight the promising potential of natural pine resin-based rosin, a bio-based and sustainable polymer for developing advanced electrospun membranes for air filtration.