What Is ELISA Kit?
All ELISA kits offered by DL Develop are either in sandwich format, or competitive inhibition format. In a sandwich format ELISA (a direct detection method), a capture antibody is first immobilized on the well of the microplate. Following that, the sample is added and the antigen of interest binds to the capture antibody, if it is present. A biotin conjugated antibody preparation is also added to the well that is specific for the analyte of interest. Next, the detection solution conjugated to an enzyme is added to the well. TMB substrate is then also added to the well, and if the analtye of interest, biotin conjugated antibody, and conjugated enzyme are present, a change in colour will occur. This reaction is stopped with a sulphuric acid solution, and the final colour change can then be measured with a spectrophotometer at 450nm. The concentration of the analyte of interest is calculated using the values from the standard curve.
A competitive inhibition format ELISA (indirect detection method), is often used when the analtye of interest is a small molecule, or has a single epitope. In this format, a capture antibody is again immobilized onto the well of the microplate. In this format, the sample, containing unlabeled analyte of interest, are added to the well at the same time as a solution of labelled analyte of interest. This results in a competitive inhibition reaction with the immobilized capture antibody. After incubation, any unbound analyte is washed away. Then, a detection solution conjugated to an enzyme is added to the well. TMB substrate is also added, and a colour change will take place. This reaction is stopped with a sulphuric acid solution, and the final colour change can then be measured with a spectrophotometer at 450nm. In this case, the amount of bound enzyme conjugate, and the intensity of the colour that develops is reverse proportionate to the amount of analyte of interest in the sample. The concentration of the analyte of interest is calculated using the values from the standard curve.
DL Develop is pleased to offer a large range of over 6000 different ELISA kits with a variety of reactivities including human, mouse, rat, porcine, canine, bovine, simian, and more. We also offer customization services if you have a special request, or need a custom-made ELISA kit. We look forward to helping you with your research!