Biosensor for Detection of Methicillin-Resistant Staphylococcus Aureus

Abstract

Bacterial pathogens are ubiquitous in nature and are important targets for detection in various applications. In the healthcare industry, Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterial pathogen that is resistant to many antibiotics. MRSA, if not treated promptly, can cause severe complications such as bloodstream infections, pneumonia, and surgical site infections leading to sepsis and eventual death [1]. Current conventional detection methods for pathogens usually take a few hours to days for identification and need skilled experts and tools such as cefoxitin disk screen tests, latex agglutination tests, and real-time PCR for analyses [2]. Biosensors, on the other hand, are simple, easy to use, and provide rapid results as well as aid in real-time monitoring. Specifically, electrochemical biosensors are advantageous over conventional methods with their ease of use, high specificity and sensitivity [3]. In the current work, a carbon nanotube-based impedimetric biosensor was developed for rapid and selective detection of live MRSA cells [4]. MRSA USA300 specific phage SATA-8505 was used as the recognition element for selective detection of its host bacteria cells. The detection mechanism uses an impedimetric measurement of the resistance changes on an electrode, where bacteriophages were immobilized onto functionalized carbon nanotube using an electric field-induced, charge-directed orientation strategy. Infectivity study using disk diffusion methods showed activity retention of immobilized bacteriophages on the electrodes. The established biosensor showed high selectivity toward MRSA USA300. The biosensor could potentially be integrated into lab-on-a-chip platforms for point of care use and for other health-care associated pathogens, such as Pseudomonas aeruginosa and Klebsiella pneumoniae.