title: Novel Approach of a Phage-Based Magnetoelastic Biosensor for the Detection ofSalmonella entericaserovar Typhimurium in Soil.
abstract: To date, there has been no employment of a magnetoelastic (ME) biosensor method to detectSalmonella entericaserovar Typhimurium in soil. The ME biosensor method needs to be investigated and modified for its successful performance. The filtration method, cation-exchange resin method, and combinations of both methods were employed for the extraction ofS. Typhimurium from soil. The number ofS. Typhimurium and the resonant frequency shift of the ME sensor were then compared using a brilliant green sulfa agar plate and an HP 8751A network analyzer. A blocking study was performed using bovine serum albumin (BSA), polyethylene glycol (PEG), and casein powder suspension. Finally, the modified ME biosensor method was performed to detectS. Typhimurium in soil. The number ofS. Typhimurium was significantly decreased from 7.10 log CFU/soil to 4.45-4.72 log CFU/soil after introduction of the cation-exchange resin method. The greatest resonant frequency shift of the measurement sensor was found when employing centrifugation and filtration procedures. The resonant frequency shift of the PEG-blocked measurement sensor was 3,219 ± 755 Hz, which was significantly greater than those of the BSA- and casein-blocked ME sensor. The optimum concentration of PEG was determined to be 1.0 mg/ml after considering the resonant shift and economic issue. Finally, the modified ME biosensor method was able to detectS. Typhimurium in soil in a dose-response manner. Although these modifications of the ME biosensor method sacrificed some advantages, such as cost, time effectiveness, and operator friendliness, this study demonstrated a novel approach of the ME biosensor method to detectS. Typhimurium in soil.
authors.affiliation: School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
authors.forename: Mi-Kyung
authors.initials: MK
authors.lastname: Park
authors.affiliation: Materials Research and Education Center, Auburn University, Auburn, AL 36849, USA.
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Chin
mesh_terms: D001435:Bacteriophages / Q000737:chemistry / Q000502:physiology*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D008280:Magnetics / Q000295:instrumentation / Q000379:methods*; D012486:Salmonella typhimurium / Q000737:chemistry / Q000254:growth & development / Q000302:isolation & purification* / Q000821:virology; D012988:Soil Microbiology
keywords: Salmonella Typhimurium; Soil; blocking reagent; extraction; phage-based magnetoelastic biosensor