Studies on purification of methamidophos monoclonal antibodies and comparative immunoactivity of purified antibodies.
OBJECTIVE
To purify Methamidophos (Met) monoclonal antibodies with two methods and compare immune activity of purified antibodies.


METHODS
Caprylic acid ammonium sulphate precipition (CAASP) method and Sepharose protein-A (SPA) affinity chromatography method were used to purify Met monoclonal antibodies, UV spectrum scanning was used to determine protein content and recovery of purified antibodies, sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) was used to analyze the purity of purified antibodies, and enzyme-linked immunosorbent assay (ELISA) was used to determine immune activity of purified antibodies.


RESULTS
Antibody protein content and recovery rate with CAASP method were 7.62 mg/mL and 8.05% respectively, antibody protein content and recovery rate with SPA method were 6.45 mg/mL and 5.52% respectively. Purity of antibodies purified by SPA method was higher than that by CAASP method. The half-maximal inhibition concentration (IC50) of antibodies purified by SPA to Met was 181.26 microg/mL, and the linear working range and the limit of quantification (LOD) were 2.43-3896.01 microg/mL and 1.03 microg/mL, respectively. The IC50 of antibodies purified by CAASP to Met was 352.82 microg/mL, and the linear working range and LOD were 10.91-11412.29 microg/mL and 3.42 microg/mL, respectively.


CONCLUSIONS
Antibodies purified by SPA method are better than those by CAASP method, and Met monoclonal antibodies purified by SPA method can be used to prepare gold-labelled testing paper for analyzing Met residue in vegetable and drink water.
Zhao
Su-Qing
SQ
Zhongshan Medical School, Sun Yat-Sen (Zhongshan) University, Guangzhou 510089, China. suqingz@hotmail.com
Sun
Yuan-Ming
YM
Zhang
Chun-Yan
CY
Huang
Xiao-Yu
XY
Zhang
Hou-Rui
HR
Zhu
Zhen-Yu
ZY
D000911:Antibodies, Monoclonal / Q000276:immunology*; D002846:Chromatography, Affinity; D002847:Chromatography, Agarose; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005506:Food Contamination; D005638:Fruit; D007306:Insecticides / Q000276:immunology*; D009946:Organothiophosphorus Compounds / Q000276:immunology*; D010573:Pesticide Residues / Q000032:analysis* / Q000276:immunology; D014675:Vegetables
D000911:Antibodies, Monoclonal; D007306:Insecticides; D009946:Organothiophosphorus Compounds; D010573:Pesticide Residues; C014655:methamidophos