title: An immunonanogold resonance scattering spectral probe for rapid assay of human chorionic gonadotrophin.
abstract: BACKGROUND
  Several assays for human chorionic gonadotrophin (hCG) such as radioimmunoassay and fluorescence immunoassays were reported. So far, there was no report about the immunonanogold resonance scattering spectral (ING-RSS) assay based on the immunoreaction and resonance scattering (RS) effect.
  
  
  METHODS
  Three ING-RSS probes for hCG were prepared, using nanogold in size of 8, 10, 13 nm to label rabbit hCG antiserum (anti-hCG).
  
  
  RESULTS
  In citric acid-Na(2)HPO(4) buffer solution and in the presence of polyethylene glycol (PEG)6000, the immunoreaction between hCG and nanogold-labeled anti-hCG took place, the immunonanogold-complex was formed and deposited. The decreased intensity DeltaI(RS) for the nanogold in sizes of 8, 10, 13 nm was proportional to hCG concentration in the ranges of 40-10000, 40-10000 and 40-8000 mIU/ml, with the detection limits of 19.4, 15.1 and 13.6 mIU/ml, respectively. The hCG in urine samples were assayed by the ING-RSS assay, and by immunospectrophotometry. The results of both assays showed a close correlation.
  
  
  CONCLUSIONS
  This assay has simplicity, sensitivity and good selectivity for quantitative determination of hCG.
authors.affiliation: School of Environment and Resource, Guangxi Normal University, Guilin 541004, China. zljiang@mailbox.gxnu.edu.cn
authors.forename: Zhi-Liang
authors.initials: ZL
authors.lastname: Jiang
authors.forename: Ming-Jing
authors.initials: MJ
authors.lastname: Zou
authors.forename: Ai-Hui
authors.initials: AH
authors.lastname: Liang
mesh_terms: D002021:Buffers; D006063:Chorionic Gonadotropin / Q000032:analysis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007118:Immunoassay / Q000379:methods*; D053768:Metal Nanoparticles; D046529:Microscopy, Electron, Transmission; D015335:Molecular Probes
chemical_list: D002021:Buffers; D006063:Chorionic Gonadotropin; D015335:Molecular Probes