Development of an enzyme-linked immunosorbent assay for toosendanin.
Enzyme-linked immunosorbent assays (ELISAs) were developed by using polyclonal antibody for toosendanin (TSN), a biopesticide from Melai toosendan Sieb. et Zucc. Their application in the determination of this analyte in spiked cabbage, tomato and apple samples was studied. The haptens, 28-hemisuccinyl-TSN (TSN-S) and 28-hemiglutaryl-TSN (TSN-G) were synthesized by using esterification. Immunogen and coating antigen were synthesized by using the mixed anhydride reaction and active ester protocol, respectively. Rabbits were immunized with TSN-G-BSA and TSN-S-BSA. Using the selected antibody and coating antigen, an indirect competitive ELISA for TSN was developed, which showed an IC(50) value of 1.023 microg mL(-1), with a detection limit of 0.009 microg mL(-1). A direct competitive ELISA using an enzyme tracer was also developed. The assay showed an IC(50) value of 0.840 microg mL(-1) with a detection limit of 0.014 microg mL(-1). Both assays displayed high cross-reactivity to a closely structurally related compound. Recoveries of TSN from both immunoassays of fortified samples ranged from 76.4% to 113.2% and 75.1% to 132.3%, respectively. Linear regression analysis showed good correlation between the TSN concentrations derived from ELISA and HPLC analyses, which suggested that the ELISA is a convenient supplementary analytical tool for monitoring TSN.
Zhang
Jing
J
R&D Center of Biorational Pesticides, Northwest A & F University, 22 Xinong Road, Yangling, Shaanxi 712100, China.
Feng
Gang
G
Luo
Li
L
Yu
Xiang Yang
XY
Ma
Zhi Qing
ZQ
Feng
Jun Tao
JT
Liu
Xian Jin
XJ
Zhang
Xing
X
D000818:Animals; D000918:Antibody Specificity; D003429:Cross Reactions / Q000276:immunology; D004365:Drugs, Chinese Herbal / Q000032:analysis* / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay / Q000295:instrumentation* / Q000379:methods*; D006241:Haptens / Q000737:chemistry / Q000276:immunology; D007106:Immune Sera / Q000032:analysis / Q000276:immunology; D008297:Male; D015394:Molecular Structure; D011817:Rabbits; D014315:Triterpenes
D004365:Drugs, Chinese Herbal; D006241:Haptens; D007106:Immune Sera; C036454:toosendanin; D014315:Triterpenes