[Methodological study on magnetic enzymic immunoassay for detecting free hCGbeta subunit].
OBJECTIVE
To establish a novel magnetic enzyme immunoassay (MEIA) for detecting human choriogonadotropin free beta subunit (hCGbeta).


METHODS
Two monoclonal antibodies (mAb) were used for conjugating with FITC and with alkaline phosphatase(AP) respectively, which incorporated magnetic solid phase separation. Magnetic beads were coupled with sheep anti-FITC antibody as solid phase, and phenolphthalein monophosphate was used as substrate to set up MEIA for detecting hCGbeta.


RESULTS
The sensitivity of hCGbeta MEIA kit reached 0.1 IU/L. The intraassay variation and inter-assay variation was 8.5% and 14% respectively, with the average recovery rate of dilution of 92.5%. The kit showed no cross reactivity to LH, TSH and FSH, while a cross reactivity of 1.2% to intact hCG at concentration of 1000 IU/L. The time of efficacy of hCGbeta MEIA kit was longer than 14 months.


CONCLUSIONS
hCGbeta MEIA kit is better than hCGbeta radio immunoassay and ELISA kit, which can provide a high-qualitative and cheap hCGbeta kit for market.
Liu
Zhen-shi
ZS
Biology Science and Technology College, Huazhong Science and Technology University, Wuhan 430070, China. zhenshi-liu@sohu.com
Zhou
Hao
H
Chen
Hai-sheng
HS
Xie
Jing
J
Lu
Xin
X
Yang
Xiang-liang
XL
D000911:Antibodies, Monoclonal / Q000032:analysis; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000032:analysis* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007124:Immunoenzyme Techniques / Q000379:methods*; D008280:Magnetics; D008722:Methods; D012680:Sensitivity and Specificity
D000911:Antibodies, Monoclonal; D018997:Chorionic Gonadotropin, beta Subunit, Human