title: Development of a one-step immunochromatographic strip test using gold nanoparticles for the rapid detection of Salmonella typhi in human serum.
abstract: An immunochromatographic strip test using gold nanoparticles was developed for the rapid detection of Salmonella typhi (S. typhi) in human serum. The strip test based on the principle of sandwich immunoassay by the specific binding of antigens from S. typhi O901 and antibody of S. typhi O901 on a nitrocellulose membrane. Antibody-gold nanoparticle conjugate was used as the label and was coated onto a glass fiber membrane, which was used as a conjugate pad. To create a test and control zone, antibody of S. typhi O901 and an anti-IgG were dotted on the nitrocellulose membrane, respectively. Positive samples were displayed as red dots at the test and control zones of the nitrocellulose membrane, while negative samples resulted in a red dot only in the control zone. The limit of detection (LOD) was found to be 1.14×10(5) cfu mL(-1), which could be visually detected by the naked eye within 15 min. This strip test provided a lower detection limit and analysis time than a dot blot immunoassay (8.88×10(6) cfu mL(-1) for LOD and 110 min for reaction time). In addition, our immunochromatographic strip test was employed to detect S. typhi in human serum effectively, with high accuracy. This strip test offers great promise for a rapid, simple and low-cost analysis of S. typhi.
authors.affiliation: Program in Biotechnology, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand.
authors.forename: Pattarachaya
authors.initials: P
authors.lastname: Preechakasedkit
authors.forename: Kulwadee
authors.initials: K
authors.lastname: Pinwattana
authors.forename: Wijitar
authors.initials: W
authors.lastname: Dungchai
authors.forename: Weena
authors.initials: W
authors.lastname: Siangproh
authors.forename: Wanpen
authors.initials: W
authors.lastname: Chaicumpa
authors.forename: Pongsri
authors.initials: P
authors.lastname: Tongtawe
authors.forename: Orawon
authors.initials: O
authors.lastname: Chailapakul
mesh_terms: D058491:Bacterial Load / Q000295:instrumentation*; D015374:Biosensing Techniques / Q000295:instrumentation; D001774:Blood Chemical Analysis / Q000295:instrumentation*; D002846:Chromatography, Affinity / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation; D011934:Reagent Strips; D015203:Reproducibility of Results; D012485:Salmonella typhi / Q000302:isolation & purification*; D012680:Sensitivity and Specificity
chemical_list: D011934:Reagent Strips; D006046:Gold