The newly developed nanocomposite coating can inhibit biofilm formation as well as kill attached bacteria, helping to address the increasing post-operative infections that are common these days due to bacterial resistance to antibiotics.
These postoperative surgical site infections (SSI), which according to the WHO affect 11 percent of patients in low- and middle-income countries, are caused by the development of biofilms (groups of bacteria growing in formation that are highly resistant to antibiotics) at the incision site or in the soft tissue inside places.
The biofilm matrix, which may originate from existing infections in the patient’s body or may be transferred from the hospital environment via potential carriers such as surgical equipment, wound dressings, or dressings/surgical sutures, acts as a physical shield against antibiotics administered during surgery. slowing down their penetration.
Therefore, it is important to have an antibacterial coating on the surface of these materials, which can act as potential sources of SSI. Antibacterial coatings containing biocides such as nanosilver, nanocopper, triclosan, and chlorhexidine are commonly used to prevent bacterial infections.
Although Triclosan and Chlorhexidine show antibacterial effects against a wide range of bacteria, they and other biocides have been found to produce cytotoxicity. As a result, there is increasing focus on the development of alternative non-cytotoxic materials with antibacterial properties.
Researchers at ARCI, an autonomous institute of the Department of Science and Technology (DST), have developed a nanocomposite coating ((named at ARCI as ATL)) by combining water repellency and biocidal properties (a combinatorial approach) that exhibits both hydrophobic and biocidal properties. behaviour. The developed coating not only inhibits biofilm formation by limiting the adhesion of bacteria and water, but also kills attached bacteria.
ATL was applied to a variety of surgical sutures made from silk, nylon, and polyglactin 910 (vicryl) along with 420 stainless steel coupons for surgical instruments and tested for biofilm inhibition against American Type Culture Collection (ATCC) and clinical isolate strains of proven biofilm-forming bacteria , such as Pseudomonas aeruginosa, Acinetobacter baumanii, Staphylococcus aureus and Escherichia coli at the Translational Health Science Technology Institute (THSTI) and LV Prasad Eye Institute (LVPEI) respectively.
ATL-coated vicryl sutures showed a higher percentage of biofilm inhibition compared to commercially available triclosan-coated antibacterial sutures. The cytotoxicity of the formulation was evaluated on the coated surface and the ATL coatings were found to be non-cytotoxic. The coatings developed in this study can be used as a non-cytotoxic alternative to commercially available antibacterial coatings, especially for medical applications on surgical sutures/surgical instruments to prevent the growth of multidrug-resistant bacteria.
