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Principle of Sandwich Chemiluminescent Immunoassay(CLIA)
Sandwich CLIA is a kind of detection method combined double antibdoy sandwich method with chemiluminescence detecion method. It regualrly includes lots of steps, which are shown below. At first, the microtiter plate has been pre-coated with an antibody specific to analyte. Then, standards or samples are added to the appropriate microtiter plate wells, the analyte in standards and samples will bound to the immobilized Ab. Next, biotin-conjugated antibody is added and binds to the analyte absorbed on the plate. The complex of two antibodies and analytes in the wells act as a “sandwich” structure. After the unbound biotin-conjugated antibody is washed away, avidin-conjugated H......
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High quality eukaryotic proteins - optimized eukaryotic expression system
Currently, prokaryotic and eukaryotic expression system are the most common used protein expression systems. And eukaryotic expression system contains yeast, mammalian and insect cell expression system, . The prokaryotic expression system is famous for its economic and efficient, but it is lack of post-translational modification. Hence, to some extent, proteins expressed by this system regularly do not possess bio-activity. The insect cell expression system involves the use of baculovirus, so it also has its own limits. Yeast expressed proteins have high level of expression, and they are easy to purify, but the proteins are also prone to degrade and the expression processes are hard......
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A Novel Marker in Cardiovascular Disease-Copeptin
Copeptin (CPP), is a part of C-terminus in arginine vasopressin (AVP) (Figure 1), a new biological marker in the recent research. Many studies show that it plays an important role in early diagnosis and prognosis of cardiovascular disease, pulmonary infection, etc. The latest research shows that copeptin combined TnI shows great value in early diagnosis of acute coronary syndrome. Why is peptide is so special? How about its structure and function? Copeptin is a kind of leucine-rich glycopeptide, AVP-derived, comprised of 39 amino acids. Until now, its biological function is not very clear, some studies suggest that it plays an important role in the processing of AVP precursor process......
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Experimental Operation Guideline-Trouble Shooting of Immunohistochemistry (IHC)
Immunohistochemistry (IHC) is also called as immunocytochemistry (ICC). It is a immunological method for qualitative and quantitative detection, as well as location of antigen in situ in cells of a tissue section, using specific and labeled antibody. It bases on the reaction of antigen and antibody, together with the color reaction of histochemistry. It skillfully combines the specificity of immunological reaction, the visibility of histochemistry and the sensitivity of molecular technology. For antigens (such as protein, peptide, enzyme, hormone, pathogen and receptor, etc) can be detected in cellular or subcellular level by visualization and amplification using microscope, it provide......
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The Detailed Preparation Method for Polyclonal Antibody
Polyclonal antibodies (pAbs) are secreted by different B cell lineages within the bodies. They are a collection of immunoglobulin molecules that react against specific antigen, each identifying a specific epitope. Polyclonal antibodies can be used in WB, IHC, Elisa, IP and so on, it is indispensable research partners in biomedical research. Here we introduce the polyclonal antibody preparation. 1 The preparation of antigen For ordinary protein, it can be obtained after the following steps: A: combinate with molecular cloning vector B: inducible expression of recombinant proteins in E. coli C. purification. Then the purified protein can be directly used as the immunogen. Small mo......
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Processing of samples for Immunohistochemistry (IHC)
Immunohistochemistry (IHC) is used for identification and localization of the target antigen/antibody by observing the staining results of sections. During the process of sectioning, it is essential to maintain the integrity of antigens. Dissolution and denaturation of antigen should be avoided during the process of staining, washing and embedding. Meanwhile, it should be eliminated that antigens diffuse to near by. Figure1 IHC image cells or tissue spaces. Tissue processing is important for obtaining good result of IHC. Living tissue, various body fluid, punctate and cells can be used for IHC analysis. Different process methods can be used according to various specimens. For livin......