Research Project
9679697
This Phase I SBIR develops and tests an approach for Modification of Polymer Surfaces using a Femtosecond Laser to Prevent Bacteria Colonization in Endotracheal Tubes. Problem to be solved: The Centers for Disease Control reports that more than 2 million people in the U.S. are infected by antibiotic-resistant bacteria (ARB) annually, with estimated direct healthcare costs near $20 billion. Morbidity, mortality, and care costs are expected to parallel the upward-trend of bacterial virulence and antibiotic resistance. Many common support devices, such as endotracheal tubes (ETTs), central venous catheters, and nasoenteric feeding tubes, are prone to infiltration by microbes. ETTs ? with over 1.6M annual in-patient intubations (in 2011) ? represent a major risk area, since the rate of ventilator-associated pneumonia (VAP) is 8-28% of patients, and in the intensive care unit VAP is the most common and fatal infection. Risk mitigation methods, such as aseptic techniques, are limited by compliance, and antiseptics and antibiotics ? though often effective ? can have unintended effects on bacteria resilience and environmental toxicity. An approach is needed that produces long-term bacteria inactivation around and inside support devices without the use of unsafe chemicals. Gap in Knowledge ? Modifying surface texture and chemistry has had mixed results in killing bacteria. Actuated Medical, Inc. (AMI) proposes that a primary reason for inconsistent outcomes is difficulty using viable methods for producing ideal topography with conventional substrates for the clinical application. AMI will use its expertise in medical devices, polymers, and endotracheal tubes, and collaborate with an immunology expert from The Pennsylvania State University and laser machining experts from Laser for Innovative Solutions Inc to demonstrate an ETT surface structure capable of chemical-free, bactericidal action on three prevalent microbes that cause ventilator-associated nosocomial infections. Phase I Hypothesis. Laser surface patterning of ETT prototype demonstrates significantly less viable ventilator-associated bacterial load over 24-hour exposures in vitro. Specific Aims. Aim 1 ? Demonstrate high-quality, 3D nano-patterning on medical polymers. Acceptance Criteria: Ability to pattern 0.5 cm2 area with 50-400 nm features, as confirmed with scanning electron microscopy, that maintain ?95% integrity after exposure to realistic ventilation conditions. Aim 2 ? Determine optimum bactericidal surface preparation(s) for relevant microbes through design of experiment. Acceptance Criteria: At least one surface preparation shows at least 3-log (99.9%) fewer viable colony forming units (CFUs) of P. aeruginosa, S. aureus, and A. baumannii relative to control surfaces. Aim 3 ? Demonstrate 3-log bacteria reduction in ETT form factor. Acceptance Criteria: ETT tube section with optimized laser pattern maintains at least 3-log (99.9%) fewer colony forming units of bacteria over 24 hours relative to control surfaces in biofilm-inducing conditions in vitro.
