Health & Medicine, Canada (Commonwealth Union) – Research conducted at the University of Toronto, Faculty of Applied Science and Engineering has demonstrated that mechanical deformation of medically implantable materials, like bending or twisting can have a huge effect on the production of possibly harmful biofilms.
The findings that appeared in Scientific Reports, demonstrate that even slight bending of elastomeric materials like polydimethylsiloxane (PDMS) which is also referred to as silicone opens up microscopic cracked opening presenting the ideal conditions for colonizing bacteria.
PDMS is a versatile and widely used silicone polymer. It belongs to the class of organosilicon compounds, which are based on a silicon-oxygen backbone with organic groups attached to the silicon atoms.
PDMS is characterized by its unique properties that make it suitable for various applications. It is a transparent, odorless, and inert material, exhibiting excellent thermal stability over a wide temperature range. PDMS is highly flexible and has low surface energy, resulting in its remarkable water-repellent and nonstick properties.
One of the primary applications of PDMS is in the field of elastomers. PDMS elastomers have high elongation and resilience, making them ideal for use in gaskets, seals, and O-rings. They can withstand repetitive stretching and compression without losing their mechanical properties.
The versatility and beneficial properties of PDMS have led to its widespread use in numerous industries and applications. Its combination of flexibility, thermal stability, biocompatibility, and low surface energy makes it a preferred material in areas ranging from microfluidics and biomedical engineering to cosmetics and industrial lubrication.
Ben Hatton, associate professor in the department of materials science and engineering, of the faculty and a senior author of the new study indicated that these types of materials are utilized in every kind of biomedical applications, that include catheters to tracheal tubes as well as prosthetic breast implants.
Biofilms are complex communities of organisms replicating on surfaces. As a person’s microbial cells are vulnerable to both antibiotics and the natural defensive systems of the individual, the biofilm atmosphere can guard them from these interventions, which may bring about continuous infections, as indicated by researchers.
Infections linked with medical-device biofilms, that at certain times form post-surgery, can pose a major health challenge, that can extend hospital stays or result in patients that have been discharged being re-admitted.
Hatton and his researchers are among many groups across the globe forming new materials, coatings and other approaches to block the production of biofilms that may bring about such infections.
However, with their most recent work, they studied something more fundamental: How do these colonizing microbial organisms gain a toehold in the first place?
Hatton indicated that in part, this arises out of the multidisciplinary approach they took in their group.
The researchers ran tests on various samples of silicone, that consisted of some they produced themselves along with commercial-grade medical tubing utilized as urinary catheters. This was followed by putting these samples to mechanical forces forming surface damage. Their tests demonstrated that the microcracks can be really simply produced.
The remaining samples were pressed with a rough, ridged pattern forming a series of frequently spaced microcracks.
The full set of samples were then put in a bacterial culture plate, seeding it with Pseudomonas aeruginosa, a biofilm-forming bacterium generally utilized as a model organism for these kinds of experiments. Once the growth was completed, the samples had treatment with a fluorescent dye, resulting in the attached bacteria to glow green when viewed with an optical microscope.
Van den Berg indicated that what was seen was that the bacteria very clearly chose to get attached in these microscopic cracks.
The findings are likely to give in insights on the potential infections and the precautionary measures that can be taken.
Image1:- Associate Professor Ben Hatton, left, and PhD candidate Desmond van den Berg examine bacteria samples in the lab. Credit: Neil Ta
