An immunonanogold resonance scattering spectral probe for rapid assay of human chorionic gonadotrophin.
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.
Jiang
Zhi-Liang
ZL
School of Environment and Resource, Guangxi Normal University, Guilin 541004, China. zljiang@mailbox.gxnu.edu.cn
Zou
Ming-Jing
MJ
Liang
Ai-Hui
AH
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
D002021:Buffers; D006063:Chorionic Gonadotropin; D015335:Molecular Probes