Chemiluminescence series of acridine esters to be "shipped"
Chemiluminescence analysis is a type of molecular luminescence spectroscopy. It means that when a substance undergoes a chemical reaction, due to the absorption of the chemical energy generated during the reaction, the reaction product molecule is excited to an excited state, and the excited molecule changes from the excited state. When returning to the ground state, it emits light of a certain wavelength, so chemiluminescence detection does not require other light sources, its background noise is small, and the detection sensitivity is high. It is extremely useful in the analysis of complex systems such as low-concentration test objects in biological samples. Big advantage.
In recent years, many types of chemiluminescent substances have been used in the field of clinical testing. With the deepening of the understanding of the chemiluminescence reaction mechanism and the influencing factors of the performance of chemiluminescence reagents, researchers at home and abroad have designed and synthesized a variety of new high The detection sensitivity of chemiluminescent reagents with light quantum yield has been continuously improved, and the application range has become increasingly extensive.
Chemiluminescence is a type of immunodiagnosis, which uses the specific reaction between antigen and antibody to determine the concentration of disease markers in the body to determine the body's physical state. It is widely used in infectious diseases, heart diseases, tumors, pregnancy detection, etc. . Due to its systematic advantages in safety, automated operation, test accuracy, and test speed, chemiluminescence has completely surpassed other technologies in performance, and has therefore become the mainstream of immunodiagnosis.
In 1983, Weeks first synthesized the acridinium ester AE-NHS for chemiluminescence immunoassay. The acridinium ester can be used to label antigens, antibodies, special proteins, DNA and other biological macromolecules, so as to realize the chemiluminescence analysis of biomolecules. It has high light quantum yield and low background. After coupling with proteins, antigens, antibodies, etc., the luminous efficiency is hardly affected, and it becomes an excellent chemiluminescence immunoassay labeling reagent. On this basis, the majority of researchers have then developed a variety of acridine chemiluminescent derivatives with higher luminous efficiency, better thermal stability, and stronger water solubility.
Methods of labeling nucleic acids with acridinium ester: (1) Protection of the 5'and 3'ends of the DNA probe; (2) Acridinium ester labeling: 25mM NHS acridinium ester dissolved in DMSO, and 1M HEPES buffer (PH=8.0) ), according to the condition that the molar ratio of nucleic acid probe: NHS acridinium ester = 1:5, add it to HEPES buffer and react at 37°C for 1 hour; (3) HPLC purification; beneficial effects: only one nucleic acid probe can be used in a common method An acridinium ester can be labeled at the 5'end. The method of the present invention creatively marks both ends of the acridinium ester, which directly increases the sensitivity by a factor of two.
The advantages of acridine esters are very obvious. In addition to the above, the reaction speed of acridinium ester chemiluminescence process is extremely fast, and its background is low, even if sodium hydroxide and hydrogen peroxide are present in the reaction, it can still emit light as usual. In the process of redox reaction, the conjugate is decomposed, but the luminescence of free acridine ester is not affected. Acridine ester chemiluminescent reagents are very stable, which is convenient for storage.
MOPS buffer is an important biochemical reagent used to maintain the acid-base balance and ion environment of tissue samples, protecting cell structure and function. Widely used in cell culture, tissue fixation, and immunohistochemical staining to improve experimental accuracy and reliability. Understanding the characteristics and application principles of MOPS buffer is crucial for biomedical research.