Introduction: Chemical luminescence

Introduction: Chemical luminescence is the direction of immune diagnostic upgrading iteration, chemical luminescence has become the international mainstream advanced technology of immunodiagnosis due to its high sensitivity, wide linear range, simple and fast, and wide range of clinical applications.1. The basic principle of chemical luminescence reactionChemical luminescence is the light produced during a chemical reaction and can often be described as:AB-I-Product LightsAmong them, the excitation state product produced by the reactants A and b reactions, the substance in the excitation state is unstable, quickly leaps to a lower energy state (e.g. the base state), and the energy is emitted in the form of light (usually visible light).Chemical luminescence reactions can be divided into two categories according to the way excitation substances are produced: one is the direct production of excitation products after chemical reactions of reactants in the system, and the other is fluorescent substances in the system that are easy to accept energy, which obtains the energy released by the chemical reaction and then transforms into excitation.Chemical luminescence can be used for analytical determination because the intensity of chemical luminescence is related to the rate of chemical luminescence, so all the factors that affect the reaction rate can be used as the basis for establishing the measurement method.2. The basic principle of immunity2.1 AntigenAntigens are substances that cause specific immune responses in the body. When antigens enter the body, they stimulate the body to produce antibodies, causing cellular immunity. In immunoassays, antigens are substances that bind to antibodies. Most of the antigens that can cause antibodies in the body are proteins with relative molecular mass greater than 5000, such as HBsAg surface antigens( HBsAg), metformin (AFP) and so on. When small molecular compounds bind to polymer proteins, they cause the body to produce specific antibodies called semi-antigens, such as certain hormones, drugs, etc. The reactivity of the antigen depends on the antigen determining cluster2.2 AntibodiesAntibodies are immunoglobulins (Igs) that bind specifically to antigens. Igs fall into five categories: Ig, IgA, IgM, IGD, and IgE. Immunoassay related to IgG and IgM. Ig consists of two light chains (l) and two heavy chains (h). Ig's light chains are the same, with and two types. The heavy chain structures of the five Igs are different, which determines their antigens. The heavy chains of IgG and IgM are called chains and chains, respectively.2.3 Antibody productionWhen the body is stimulated by antigens, B lymphocytes produce antibodies. Antibody-containing serums are called anti-serums, and each row of B cells produces only antibodies for a certain cluster of antigen decisions. If multiple antigens or antigens containing multiple antigen-determining clusters are injected into the body, multiple B cells produce a variety of antibodies that are present in the immune serum. The anti-serum used in immunoassays is prepared by using antigen immune rabbits, sheep or horses. Antibody-producing B cells can be fused into hybrid tumor cells in vitro with highly fertile tumor cells. Isolate individual hybrid tumor cells and culture them in vivo or in vitro to secrete monoclonal antibodies. Monoclonal antibodies target only one antigen-determining cluster and are highly specific. Monoclonal antibodies are usually prepared in antigen-immune mice. Immune spleen cells (including B cells that produce antibodies) fuse with mouse tumor cells, isolate hybrid tumor cells, and are inoculated in the mouse abdominal cavity. The resulting ascites contain high concentrations of monoclonal antibodies. 2.4 The basic principles of immunoassay and their application in clinical testingImmunoassay is a highly selective biochemical method based on antigen and antibody-specific binding. Immunoassays are divided into marker immunoassays and unlabeled immunoassays based on whether or not they are labeled. After the direct binding of antigens and antibodies, some changes occur in the properties of science and chemical properties, such as precipitation, which can be used to detect antibodies or antigens, i.e. to achieve unmarked immunoassay. However, it is difficult to detect traces in this way. Therefore, due to the lack of measurable signals in antibody-antigen reactions, probe technology has been introduced into the analysis for on-line detection. Radioimmune analysis is the most mature method of marker immunoassay, but its application is limited due to the harm of radioactive material to human body. In order to replace radioimmune analysis, high sensitivity non-radiological immunoassay analysis has become a hot topic in recent years. Immunoassay methods are divided into radioimmune analysis and non-radioimmune analysis based on whether the markers are radioactive or not. Non-radiological imm