Detection of primary antibodies

amplification and visualization

The PROGEN portfolio contains about 20 antibodies against 4 species for research use. Get into the flow by combining PROGEN´s primary and secondary antibodies for your immunostaining. The primary and secondary antibodies offered by PROGEN are carefully tested for combined use. Thorough internal & external validation of these primary and secondary antibody combinations allows easy establishment of IHC and western blot assay with minimal optimization. Take advantage of test sample sizes and product sets that minimize optimization effort.
•    Antibodies offered are basically monoclonal and polyclonal IgGs.
•    Monoclonal & polyclonal IgGs
•    Against mouse, rabbit, guinea pig & chicken
•    Suitable for IF, ELISA and WB (verified for use with PROGEN's primary antibodies)

View Secondary Antibodies

Why using a secondary antibody?

Methods in which secondary antibody are used to recognize another primary antibody are referred to as indirect labelling. The secondary antibody is usually bound directly to a reporter or marker molecule.  This can be a (fluorescent) dye or an enzyme that converts a substrate into a dye or a signal enhancing conjugate such as biotin may be added upstream. In contrast to direct detection with an antibody, the use of secondary antibodies has advantages, as usually several secondary antibodies can bind to one primary antibody.

Potential benefits

  • Signal amplification through binding of several secondary antibodies
  • A single secondary antibody can be used for several primary antibodies


  • Identification of specific proteins (e.g. WB)
  • Visualization & localization studies (e.g. IF)
  • Analysis of protein-protein interaction

Crucial considerations

to choose the right secondary antibody

There are some important points to follow for choosing the right secondary antibody. The first important point concerns species reactivity. As a rule, a species is chosen from which the primary antibody originates. Especially in the case of indirect multiple labelling, attention must be paid to cross-reactivity. The next important aspect is the choice of host species of the secondary antibody.  In order to avoid cross-reactions between secondary antibodies, all secondary antibody conjugates should be from the same host species in the case of indirect multiple labelling with unconjugated primary antibodies. The third step is to choose the structure of the secondary antibody: total molecule (H+L), F (ab') 2 or Fab fragment. Another important criterion is specificity, which defines which part of the primary antibody is recognized by the secondary antibody. Since polyclonal antibodies of the IgG type (e.g. from rabbit, goat, chicken, etc.) or monoclonal antibodies from mouse, rat or hamster are mainly used for immunological assays, secondary antibodies should have the highest possible sensitivity for this primary antibody. An important selection criterion is the choice of conjugates, which depends on the method used and the desired type of detection (enzymatic, amplified, direct, etc.). The last important criterion is the degree of adsorption, since Ig-specific antibodies of a given species may cross-react to a greater or lesser extent with immunoglobulins and serum proteins of other species. For this reason, to eliminate cross-reactivity with molecules of that species, antibodies are partially preadsorbed to immunoglobulins and serum proteins of one or more foreign species.


single domain antibodies (sdAbs)

  • protag-HiSec: fluorescently labeled secondary antibodies
  • Against mouse, rabbit and chicken IgY
  • Each antibody is available with 9 different fluorophores
  • Suitable for high resolution microscopy

Top Selling Secondary Antibodies

anti-rabbit IgG goat polyclonal, HRP conjugate
Cat. No: 90003
  • HRP conjugate
  • Goat polyclonal
  • Suitable for ELISA and WB
  • Reacts with rabbit


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