Colloidal gold-based immunochromatographic assay for detection of botulinum neurotoxin type B.
A rapid immunochromatographic assay was developed to detect botulinum neurotoxin type B (BoNT/B). The assay was based on the sandwich format using polyclonal antibody (Pab). The thiophilic gel purified anti-BoNT/B Pab was immobilized to a defined detection zone on a porous nitrocellulose membrane and conjugated to colloidal gold particles that served as a detection reagent. The BoNT/B-containing sample was added to the membrane and allowed to react with Pab-coated particles. The mixture was then passed along the porous membrane by capillary action past the Pab in the detection zone, which will bind the particles that had BoNT/B bound to their surface, giving a red colour within this detection zone with an intensity proportional to BoNT/B concentration. In the absence of BoNT/B, no immunogold was bound to the solid-phase antibody. With this method, 50 ng/ml of BoNT/B was detected in less than 10 min. The assay sensitivity can be increased by silver enhancement to 50 pg/ml. The developed BoNT/B assay also showed no cross reaction to type A neurotoxin (BoNT/A) and type E neurotoxin (BoNT/E).
Chiao
Der-Jiang
DJ
Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan, ROC.
Shyu
Rong-Hwa
RH
Hu
Chieh-Shen
CS
Chiang
Hsien-Yuan
HY
Tang
Shiao-Shek
SS
D001905:Botulinum Toxins / Q000032:analysis*; D019274:Botulinum Toxins, Type A; D002853:Chromatography, Liquid / Q000379:methods*; D003102:Colloids / Q000737:chemistry*; D003429:Cross Reactions; D006046:Gold / Q000737:chemistry*; D012680:Sensitivity and Specificity
D003102:Colloids; C096323:rimabotulinumtoxinB; D006046:Gold; D001905:Botulinum Toxins; D019274:Botulinum Toxins, Type A