title: [Development and systematical evaluation of an up-converting phosphor technology based lateral flow assay for quantitative detection of Burkholderia pseudomallei].
abstract: OBJECTIVE
  To develop an up-converting phosphor technology-based lateral-flow (UPT-LF) assay for rapid quantitative detection of Burkholderia pseudomallei on site.
  
  
  METHODS
  The strip Bps-UPT-LF strip was prepared with up-converting phosphor (UCP) particles as the bio-label using double-antibody sandwich method. Detection performance, including sensitivity, quantitative accuracy, precision, and specificity, were first evaluated using bacterial suspensions of Burkholderia pseudomallei, the related species and the strains which had similar routes of transmission with serial standard concentrations diluted by phosphate buffer, then biological and chemical reagents and simulated samples with series concentrations were employed for sample tolerance evaluation, while the operation error during on site detection was also evaluated through adjusting liquid measure.
  
  
  RESULTS
  The whole detection was accomplished within 20 minutes, and the sensitivity was 10(4) CFU/ml with linear quantitative range from 10(4) CFU/ml to 10(7) CFU/ml, which covered four orders of magnitude. Bps-UPT-LF strip demonstrated high specificity with the absence of any false-positive result even at 10(7) and 10(8) CFU/ml of non-specific bacterial contamination. Not only Bps-UPT-LF strip could tolerate to high concentration of the extreme acid and basic matter (pH 1-12), saline matter (≤ 2 mol/L mixture of NaCl and KCl), viscous materials (≤ 50 g/L of PEG 20000 and ≤ 20% of glycerol) and bio-macromolecule (≥ 400 g/L of bovine serum albumin or ≥ 80 g/L of casein), but also it can directly detect animal, environmental and powder specimen, such as ≥ 400 g/L of milk powder, flour powder, fruit juice, fresh and decomposed viscera, and ≤ 200 g/L of putty powder, sucrose, gourmet powder, and soil. Operation errors of liquid measure had few effects on sensitivity and specificity, including -50%-200% of sample, -22%-44% of sample-treating buffer and -30%-30% of loading mixture.
  
  
  CONCLUSIONS
  The good detection performance and tolerance performance bring the bright future for Bps-UPT-LF strip to detect Burkholderia pseudomallei on site rapidly and quantitatively for nature foci surveillance and anti-bioterrorism.
authors.affiliation: Department of Pathogenic Biology, Taishan Medical University, Tai'an 271000, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Hua
authors.affiliation: Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences, Beijing 100071, China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Department of Endocrinology, Navy General Hospital, Beijing 100048, China.
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Wang
authors.affiliation: Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences, Beijing 100071, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhou
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhao
authors.forename: Xiao
authors.initials: X
authors.lastname: Liu
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Li
authors.forename: Ruifu
authors.initials: R
authors.lastname: Yang
authors.affiliation: Email: alyu@tsmc.edu.cn.
authors.forename: Ailian
authors.initials: A
authors.lastname: Yu
mesh_terms: D000818:Animals; D016957:Burkholderia pseudomallei; D002846:Chromatography, Affinity; D012680:Sensitivity and Specificity