Antibody Engineering for Pursuing a Healthier Future

Saeed, Abdullah F. U. H.; Wang, Rongzhi; Ling, Sumei; Wang, Shihua

The technique comprises various components and steps. A sample pad acts as a sponge and absorbs the fluids. Then, fluids migrate to a conjugate pad containing protein conjugates immobilized on the surface of bio-active particles in a salt-sugar matrix that reacts with the antigen. Next, sample fluids dissolve the conjugate salt-sugar matrix and antibody-particles. The fluid mix flows through the porous structure causing the analyte to bind with particles while migrating further through the third capillary bed. Finally, there is a third capture molecule in striped areas that binds to the fluid mix containing analytes and the particle consequently changes color (Yu et al., 2012) . LFTs can be used as a competitive or sandwich assay. Latex (blue color), nanometer-sized particles of gold (red color), or fluorescent or magnetic labeled particles are also used (Seydack, 2005) . The technique is qualitative, nevertheless, the quantity of analyte in a sample can be measured by the intensity of the test line color. It is usually carried out by optical and non-optical lateral flow readers or biosensors (LFBs) such as complementary metal-oxide semiconductor (CMOS) or a charge-coupled device (CCD) and magnetic immunoassay (MIA) (Gui et al., 2014) .