Effect of Polymer Demixed Nanotopographies on Bacterial Adhesion and Biofilm Formation

Abstract

As the current global threat of antimicrobial resistance (AMR) persists, developing alternatives to antibiotics that are less susceptible to resistance is becoming an urgent necessity. Recent advances in biomaterials have allowed for the development and fabrication of materials with discrete surface nanotopographies that can deter bacteria from adhering to their surface. Using binary polymer blends of polystyrene (PS), poly(methyl methacrylate) (PMMA) and polycaprolactone (PCL) and varying their relative concentrations, PS/PCL, PS/PMMA and PCL/PMMA polymer demixed thin films were developed with nanoisland, nanoribbon and nanopit topographies. In the PS/PCL system, PS segregates to the air-polymer interface, with the lower solubility PCL preferring the substrate-polymer interface. In the PS/PMMA and PCL/PMMA systems, PMMA prefers the air-polymer interface due to its greater solubility and lower surface energy. The anti-adhesion efficacy of the demixed films were tested against Pseudomonas aeruginosa (PA14). PS/PCL and PCL/PMMA demixed films showed a significant reduction in cell counts adhered on their surfaces compared to pure polymer control films, while no reduction was observed in the counts adhered on PS/PMMA demixed films. While the specific morphology did not affect the adhesion, a relationship between bacterial cell and topographical surface feature size was apparent. If the surface feature was smaller than the cell, then an anti-adhesion effect was observed; if the surface feature was larger than the cell, then the bacteria preferred to adhere.

Nanotopography of Polystyrene/Poly(methyl methacrylate) for the Promotion of Patient Specific Von Willebrand Factor Entrapment and Platelet Adhesion in a Whole Blood Microfluidic Assay

“…Small differences within the deconvoluted C1s spectra components are observed, however, and it is likely that this is attributable to slight differences in the orientation of the polymer chains as a result of the spin coating process [ 33 ]. These findings are consistent with previous studies by the authors of the chemical properties of spin coating of PS/PMMA blends in nitrogen, which leads to the component with the higher surface energy (PMMA) being segregated at the uppermost surface [ 28 , 29 , 36 ]. This suggests that, notwithstanding the volatility of the chloroform solvent, which results in evaporation before the system has reached thermodynamic equilibrium [ 37 ], the segregation of PMMA to the uppermost surface still occurs.…”

Efficient Biofilms Eradication by Enzymatic-Cocktail of Pancreatic Protease Type-I and Bacterial α-Amylase

“…In this process the proteins and polysaccharides from EPS play a vital role [ 14 ]. Thus, enzymes which can degrade these proteins and polysaccharides are of high importance in biofilm treatment processes [ 5 , 16 , 17 , 18 , 19 , 20 ]. Enzymatic degradation of EPS induces susceptibility of the microbes to anti-microbial agents.…”

Green Method for the Preparation of Durable Superhydrophobic Antimicrobial Polyester Fabrics with Micro-Pleated Structures

“…A biofilm is a community of microorganisms characterized by bacterial cells that are irreversibly attached to a substratum or interface, or to each other, embedded in a matrix of extracellular polymeric substances that they have produced [ 10 , 11 ]. Researchers have observed that biofilm formation follows a sequential colonization, from early colonizers such as streptococci, to bacterial proliferation, and to the final formation of biofilm [ 12 ], in which surface properties, such as morphology, chemistry, and surface energy, are the main factors affecting interfacial interactions [ 13 , 14 ]. According to the Cassie–Baxter wettability model, superhydrophobic surfaces (characterized by a water contact angle (WCA) of ≥ 150° and sliding angle SA of ≤ 10°) exhibit non-wetting, anti-fouling, and self-cleaning properties, resulting from the combination of low surface energy and surface roughness [ 15 , 16 ].…”