Antistaphylococcal Nanocomposite Films Based on Enzyme−Nanotube Conjugates

Abstract

Infection with antibiotic-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) is one of the primary causes of hospitalizations and deaths. To address this issue, we have designed antimicrobial coatings incorporating carbon nanotube-enzyme conjugates that are highly effective against antibiotic-resistant pathogens. Specifically, we incorporated conjugates of carbon nanotubes with lysostaphin, a cell wall degrading enzyme, into films to impart bactericidal properties against Staphylococcus aureus and Staphylococcus epidermidis. We fabricated and characterized nanocomposites containing different conjugate formulations and enzyme loadings. These enzyme-based composites were highly efficient in killing MRSA (>99% within 2 h) without release of the enzyme into solution. Additionally, these films were reusable and stable under dry storage conditions for a month. Such enzyme-based film formulations may be used to prevent growth of pathogenic and antibiotic-resistant microorganisms on various common surfaces in hospital settings. Polymer and paint films containing such antimicrobial conjugates, in particular, could be advantageous to prevent risk of staphylococcal-specific infection and biofouling.Keywords carbon nanotube; lysostaphin; nanocomposite; antimicrobial film; methicillin-resistant Staphylococcus aureus (MRSA) It is estimated that out of the expected 2 billion people carrying Staphylococcus aureus (S. aureus) worldwide, up to 53 million individuals are infected with methicillin-resistant S. aureus (MRSA).1 Specifically, S. aureus -related diseases such as septicemia and pneumonia are responsible for a large number of hospitalizations (ca. 480,000 in 2005) and deaths (nearly 11,000 in 2005) in the U.S., alone.2 Staphylococcal infection caused by S. aureus and Staphylococcus epidermidis (S. epidermidis) is also a major concern in patients with indwelling devices such as catheters, heart valves, and prostheses.3 While medical and surgical equipment, hospital rooms, and various other objects in hospital settings provide an kaner@rpi.edu, dordick@rpi.edu. Supporting Information Available: Mechanism of Lst-mediated cell wall degradation, bactericidal activity of films against S. epidermidis, bactericidal efficiency of six-times washed films, and SEM characterization of films with different Lst loadings. This material is available free of charge via the Internet at http://pubs.acs.org. NIH Public AccessAuthor Manuscript ACS Nano. Author manuscript; available in PMC 2011 July 27.Published in final edited form as: ACS Nano. 2010 July 27; 4(7): 3993-4000. doi:10.1021/nn100932t. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript easily accessible platform for pathogenic bacteria to settle and proliferate, any surface once touched by an infected person serves as a breeding ground for such pathogens.Considering the magnitude of pathogen-related complications and the assistance of various surfaces in growth and spread of these pathogens, significant attention has ...

Antimicrobial Polymers in Solution and on Surfaces: Overview and Functional Principles

“…Dordick et al published a coating based on lysostaphin, immobilized on carbon nanotubes [121]. The coating is long-term active and efficiently kills MRSA on contact.…”

Endolysins as Antimicrobials

“…Similarly, the same combination was found to kill MRSA on human skin within 5 minutes using an ex vivo assay (Desbois et al, 2010). In one unique application, lysostaphin attached to nanotubes and mixed with latex paint was shown to retain anti-staphylococcal properties on painted surfaces (Pangule et al, 2010) For endolysins, only PlyC has been tested specifically as an environmental disinfectant (Hoopes et al, 2009). PlyC lyses several streptococcal species including S. equi, the causative organism of equine strangles disease.…”

White Light-Activated Antimicrobial Paint using Crystal Violet

“…Many techniques have been suggested for application to soft and hard surfaces, including silver or copper coated surfaces [20][21][22] , self-cleaning surfaces 23,24 and enzyme or bacteriophage immobilized surfaces 25,26 . In addition, the incorporation of light-activated antimicrobial agents (LAAAs) into surfaces is considered a promising technique [27][28][29] .…”