| Lateral flow test is a new kind of immunoassay developed from 1990s.With the advantages of rapidness,simplicity,single-test,economy, lateral flow has been used in the following field : medical test,quality monitor of food,supervision of environment,agriculture and stockbreeding,test and quarantine in custom,legal medical verdict. Nowadays lateral flow test was developed towards for quantitative test,sensitivity improvement,multiplex detection,change of lateral flow system. Optical quantitative lateral flow test with the colloidal gold and colored latex as signal material was based on the detection of light intensity reflected from the signal material on the surface of the nitromembrane. The sensitivity of the quantitative lateral flow test based on colliodal was low. So the quantitative lateral flow test based on immunomagnetic nanobeads has become the research hot recently.In this paper , the well dispersed immunomagnetic beads whose diameter was 259nm were prepared by the reaction between the aminos of the anti-β-hCG antibodies and the carboxyl on the surface of magnetic beads whose carboxyl groups were catalyzed by EDC/NHS. Immunomagnetic beads were used in lateral flow strips as substitute for colloidal gold. HCG was quantitative tested as model protein by lateral flow strips of immunomagnetic beads. During of the construction of lateral flow strips ,effect of some material(surfactant,ion,polymer) on the specificity and sensitivity was observed. Magnetic signal on the test line and control line of hCG in different concentration were measured by magnetic signal reader. So the hCG concentration can be quantitative tested by measure the magnetic signal of the lateral flow strip. Diameter of immunomagnetic nanobeads(250nm) are far bigger than that of the colloidal gold(40nm), lateral flow strips with immunomagnetic nanobeads substituted for colloidal gold can test quantitatively and improve sensitivity and accuracy.
|
PDF Full Text Request