INV-14052
The attachment of bacteria to surfaces, sometimes referred to as biofilm formation, often occurs in two steps. The first step is the initial attachment of the bacteria to the surface and the second is a cell-to-cell proliferation to form multilayered bacterial clusters. The initial attachment of the bacteria to the surface is thought to be affected by surface roughness, surface charge, and hydrophobicity.
Attachment of bacteria is undesirable on surfaces of devices that are intended to be placed in the body of an individual or on surfaces where materials or devices are prepared prior to insertion into an individual because of the risk of infection to the individual. Such devices include needles, tubes, implants, medical devices and the like. Attachment of bacteria is also undesirable on surfaces where food preparation takes place, as food can become contaminated prior to ingestion.
Producing surfaces that minimize adherence and/or proliferation of bacteria thereby decreasing any risks of infection is desirable.
With these objectives in mind, a team of Northeastern University inventors in collaboration with Brown University, present ‘Nanostructured Surfaces’. In this invention, fabricated surfaces of substrates characterized by at least one of surface roughness, surface charge and/or hydrophobicity where the ability of bacteria to adhere, proliferate, and/or colonize to the surface is decreased, inhibited and/or reduced. The surface is “antibacterial” to the extent that the ability of bacteria to adhere to the surface is decreased.
The nanometer scale geometry of the surface reduces the ability of bacteria to adhere, proliferate and differentiate on the surface. According to certain aspects of this invention, the etching of the surface with nano-roughing agents such as a bacterial lipase, produces a nanoscale geometry with surface roughness. These surfaces are engineered in such a way that they also exhibit a surface charge and/or hydrophobicity where the ability of bacteria to adhere to the surface is further decreased when compared to a surface having a different surface charge and/or hydrophobicity.
This altered surface energy reduces inflammation that promotes the adsorption of proteins, such as vitronection and fibronection, decreasing inflammatory cell functions to minimize bacterial function. Accordingly, these nanostructured surfaces are useful to reduce the risk of bacterial infection when the substrate is inserted or implanted into an individual.