Preparation of non-toxic green slippery liquid infused surfaces based on electrospun fiber with anti-algae and anti-bacterial properties

Microbial attachment is a problem of vital importance and economic significance, particularly in marine environments. Slippery Liquid Infused Surfaces (SLIPS) have attracted considerable interest as a solution to this challenge. In the present study, we hypothesized that Saint John's Wort Oil (SJWO) could provide an eco-friendly alternative to synthetic oils, combating marine microbial attachment with non-toxic chemicals. We developed a hydrophobic electrospun porous cellulose acetate fiber layer, coated with silica nanoparticles (SiO₂NPs), and infused with SJWO. The optimization process involved measuring sliding velocity, the number of SiO₂NP layers, the amount of lubricant, and the infusion time. The optimal configuration demonstrated a sliding velocity of 0.31 cm/s on a 10° slope. Antibacterial tests revealed that the SLIPS reduced bacterial attachment of Pseudomonas aeruginosa from 1.67 ± 0.03 × 10⁶ CFU/mL on glass substrates to 2.85 ± 0.07 × 10⁵ CFU/mL for SLIPS. Similarly, the anti-algae performance against Chlorella sp. showed a significant reduction in optical density from 0.92 ± 0.01 for glass substrates to 0.19 ± 0.01 for SLIPS, and chlorophyll content was reduced from 7.24 ± 0.19 µg/mL to 3.70 ± 0.77 µg/mL. The findings indicate that SJWO-infused SLIPS provide a robust and effective method for reducing microbial attachment.