As a chemiluminescent reagent, acridinium ester does not require a catalyst during the luminescence process. In alkaline H2O2 solution, when the molecules of acridine ester are attacked by hydrogen peroxide ions, the substituents on the acridine ring can form unstable dioxygen with C-9 and H2O2 (hydrogen peroxide) on the acridine ring. Ethane (this dioxyethane can be quickly decomposed into CO2 and electronically excited N-methylacridone, which emits photons when it returns to the ground state), then such substituted acridine compounds can be used as chemiluminescent markers.

1. Luminescence mechanism:

According to the different substituents, acridine substituents commonly used as chemiluminescent labels are divided into two categories: acridine esters and acridine sulfonamides. They all share a common acridine ring in their structure. Their luminescence mechanism is the same: in an alkaline H2O2 solution, when the molecule is attacked by hydrogen peroxide ions, unstable dioxyethane is generated, which decomposes into CO2 and electronically excited N-methyl acridine Ketones emit photons with a maximum emission wavelength of 430nm when they return to the ground state.

2. Features:

1. In the luminescence reaction, before the electronically excited state intermediate is formed, the non-luminous substituents attached to the acridine ring are separated from the acridine ring, that is, the non-luminous part is separated from the luminous part, so the luminous efficiency is basically Not affected by the structure of the substituent.

2. Chemiluminescence of acridine ester or acridine sulfonamide compounds does not require a catalyst, and can emit light in a dilute alkaline solution with H2O2. Therefore, the application of chemiluminescence detection has many advantages.

3. Acridine ester luminescent labeling substances also have the properties of large steric hindrance, good hydrolytic stability, thermal stability and high signal-to-noise ratio, and the labeling conditions are mild, the labeling rate is high, and the separation after labeling is considered It is an ideal chemical marker.

Three, advantages:

1. Low background luminescence and high signal-to-noise ratio;

2. Few interference factors in luminescence reaction;

3. Rapid concentration of light release, high luminous efficiency and high luminous intensity;

4. It is easy to connect with protein and the photon yield does not decrease after connection;

5. The marker is stable (it can be stored for several months at 2-8 ℃).

6. The luminescence of this type of compound is flash type, and the emitted light intensity reaches the maximum about 0.4s after adding the luminescence starting reagent, and the half-life is about 0.9s.

Four, application

Acridine-based chemiluminescence systems are widely used in the fields of inorganic and organic compounds, biology and pharmaceutical analysis due to the advantages of no catalyst, mild reaction conditions, and good reproducibility. Acridine ester luminescence immunoassay technology is of great help in various fields of application. According to the experimental principle of double antibody sandwich method, using acridinium ester chemiluminescence immunoassay technology combined with biotin-avidin magnetic particle separation technology to establish a A method for quantitative determination of carcinoembryonic antigen content in serum. Due to the application of acridine ester luminescence immunotechnology, the medical determination of carcinoembryonic antigen content in serum is more rapid and convenient, so that carcinoembryonic antigen patients can be treated in time, which provides great convenience and makes a big step forward in medicine. step. The accuracy rate of patients who received acridine ester chemiluminescence immunoassay technology was high, fast and convenient. The accuracy of patients who received general immunological testing was significantly lower than that of the experimental group, and it took a long time and was inconvenient. Generally speaking, the chemiluminescence immunoassay technique of acridinium ester can be popularized and continued to be studied. In the field of medicine, the application of acridinium ester chemiluminescence immunoassay technology has gradually changed into a trend to improve the speed and accuracy of medical research.