High-quality Secondary Antibodies-a Good Tool for Research of Immunology

Secondary antibodies are antibodies target to primary antibodies. The antibody (Ab), also known as an immunoglobulin, is able to provoke an immune response due to its immunogenicity. If an antibody is injected to heterogeneous host, the immunoglobulin against to this primary antibody will be secreted by activated immune system. A secondary antibody is used to combined with primary antibody that has bound to a target antigen and it can be used to increase sensitivity through the signal amplification. Secondary antibodies conjugated to enzymes and labels play an important role in the immunological experiment. That is to say, they are the key components of detection systems. Selection of an optimum secondary antibody can improve experimental effects. Generally, the following information need to be considered while choosing an appropriate secondary antibody.

1. Host animals and the class (subclass) of primary antibody

In the immunological experiment, primary antibody is used to bind to a target antigen. However, it is hard for us to distinguish whether they are binding to each other by naked eyes. Secondary antibodies conjugated to labels which could be detected by specific methods could recognize Ag-Ab complex by binding to the primary antibody, and then the signal could be used for determination of Ag-Ab combination. So, the detailed information of primary antibody need to be taken into account in the experiment.

For the polyclonal antibody (IgG class immunoglobulin is the main components, the secondary antibodies for these species will mainly be anti-IgG), the host of primary antibody needs to be taken into account. If the primary antibody is raised in a rabbit, you will need an anti-rabbit IgG secondary antibody. To meet the client’s needs, our company develops serials of secondary antibodies, including anti-human \mouse \ rat\ rabbit\ guinea pig\ cat\ dog\ pig\ bovine\ goat\ house\ chicken IgG antibody.

Monoclonal antibodies are most commonly developed in mice and occasionally in rats. The class and subclass of the monoclonal Ab is also need to be taken into consideration besides the host. For example, if the primary monoclonal Ab is mouse IgM, then it is recommended to use a secondary antibody that reacts with mouse IgM in the experiment. If the primary monoclonal Ab is one of the mouse IgG subclasses (IgG1, IgG2, IgG3), take lgG1 for example, anti-mouse IgG/IgG1 secondary antibodies is recommended to be used. 

Considering the commonly used primary Ab are IgG class immunoglobulin, secondary antibodies against to IgG class immunoglobulin of multi-species are pushed into the market.

In addition, there are thousands of rabbit derived polyclonal Ab against to different target protein in the company, and these antibodies could be used in immunogical experiment together with secondary antibody. What is more, USCNsabc01，HRP Conjugated Rabbit IgG SABC Kit designed for IHC experiment is also recommended. The kit employs the Strept Avidin Biotin-peroxidase Complex method to amplify the signal and consequently increase the sensitivity of the experiment. If the primary antibody is derived from rabbit, the USCNsabc01 may be a good choice in your IHC experiment

2. Labels of secondary antibodies

Generally, the commonly used labels for secondary antibody include enzyme, biotin, and fluorescentetc. Your application will affect your label. The application of label relies on the need of experiment. For ELISA and immunoblotting, enzyme-linked secondaries are the most popular choice, whereas for flow cytometry, a fluorescent labeled secondary antibody is used more frequently. In our company, three types of secondary antibodies are provided, horse radish peroxidase (HRP) labeled secondary antibody, biotin labeled secondary antibody, and fluorescein isothiocyanate (FITC) labeled secondary antibody

Horse radish peroxidase(HRP) labeled secondary antibodies

HRP (Horseradish Peroxidase), a 44,173.9-dalton glycoprotein, consists of colorless enzyme and dark brown iron porphyrin node and found in the roots of horseradish. So far, HRP is one of the most commonly used enzyme in immunology because it is easy to get, inexpensive, stable, and heat-resisting. HRP labeled secondary antibodies are widely used in IHC, western blot and ELISA.

 Biotin labeled secondary antibodies

 Biotin labeled secondary antibodies can bind avidin with high affinity. Biotin-Avidin system can amplify the signal to improve the sensitivity of the experiment. This kind of secondary antibody is widely used in ELISA, Western Blot, IHC, IHF, IHP, etc.

 Fluorescein isothiocyanate(FITC) labeled secondary antibodies

 FITC can bind to various of primary antibodies and it will not affect the specificity of the primary antibody. It can emit strong yellow-green fluorescent light in alkaline solution. The target protein can be detected qualitatively or quantitatively by fluorescence microscope or Flow cytometry analysis. FITC labeled secondary antibodies are usually used in IHC and ICC/IF.

The company will pay continuous attention to improve quality and quantity of the secondary antibodies.Researchers can choose the optimal secondary antibody to obtain an ideal result. In addition, we are still working on secondary antibodies linked with other labels, and new products will be pushed into the market in the near future Your attention is invited.

For more information, please visit http://www.cloud-clone.us/.