AMPPD/ADPS/N-Ethyl-N-(3-sulfopropyl)-3-methoxyaniline sodium salt

English Name: amppd; ADPS； N-Ethyl-N-(3-sulfopropyl)-3-methoxyaniline sodium salt
CAS No.: 122341-56-4
C18H23O7P=382.344781
Grade: br
Content: ≥ 98%
Physicochemical  Properties: white to almost white powder, soluble in n-butanol, dimethyl sulfoxide, etc
Purpose: biochemical research. Under alkaline conditions, amppd is enzymatically hydrolyzed by AP to form quite stable amp-d anion, which has a decomposition half-life of 2-30min and emits continuous light with a wavelength of 470nm. Its intensity reaches a peak at 15min and remains relatively stable within 15-60min. Amppd is a chemiluminescent substrate of alkaline phosphatase. In a suitable buffer, amppd is decomposed into amp-d with the catalytic hydrolysis of the enzyme. The latter emits a high-intensity light signal, and the speed of its luminescence depends on the concentration of alkaline phosphatase. When alkaline phosphatase is coupled to the hybridization probe, the presence of hybridization molecules can be detected by this system.
Storage: - 20 ℃
In this paper, the structure, luminescence mechanism, luminescence properties and characteristics of (amantadine) - 1,2-dioxane and its derivatives used in immunoassay at present are reviewed.
Key words: amppd, (amantadine) - 1,2-dioxane and its derivatives, chemiluminescence immunoassay (CLIA), luminescence mechanism, luminescence performance
At present, a variety of immunoassay methods are applied in the field of immunoassay. Among them, chemiluminescence immunoassay (CLIA) is a technology that combines immune reaction and chemiluminescence reaction to detect antigen or antibody. It is to label the luminescent substance or enzyme on the antigen or antibody. After the immune reaction is completed, the oxidant or enzyme substrate is added to emit light. By measuring the emission light intensity, the concentration of the substance to be measured is determined according to the standard curve. The main advantages of CLIA are high sensitivity, long validity period of markers, wide detection range, and full automation. CLIA has a strong vitality and has been attached great importance by clinical users and biomedical workers at home and abroad. In the past decade, CLIA has developed rapidly. Many chemiluminescent substances, CLI 2A system and fully automatic chemiluminescent instrument have been developed abroad. Different chemiluminescent substances have different luminescent mechanisms and luminescent properties, and different CLIA systems have different principles and methods. Among the many chemiluminescent molecules, 1,2-dioxane is the most efficient class of amppd 3 - (2-helical adamantane) - 4-methoxy-4 - (3-phosphoxyyl) - phenyl-1,2-dioxane. As the most representative chemiluminescent molecule in 1,2-dioxane, its chemiluminescent properties have always been the focus of research. In this paper, several kinds of (amantadine) - 1,2 - dioxane and their immunoassay systems used in immunoassay are reviewed.
(steelane) - 1,2-dioxethane and its derivatives are (steelane) - 1,2-dioxethane which can produce chemiluminescence, and its structure can be represented by the following general formula:
Among them, t is usually cycloalkane amantadine, which plays the role of stabilizing the peroxy ring; X is alkoxy group, which is used to increase the water solubility of 2-dioxane; y is the luminescent group (also called chromogenic group and fluorescent chromophore); Z is the protective group of Y, and the chemical bond between it and y can be broken by alkaline phosphatase to separate z from y. When Z is separated from the molecule by the enzyme, dioxane is decomposed into two carbonyl compounds, one containing T and the other containing X and Y. the energy released by the decomposition reaction excites y to form an unstable electron excited intermediate, which emits photons when it returns to the ground state. The wavelength and number of photons of emitted light can be changed by modifying dioxane with different substituents y, while the water solubility and decomposition kinetics of dioxane can be changed by modifying T, X and Z.
(amantadine) - 1,2-dioxane commonly used in chemiluminescence immunoassay has the following structures:
In the above molecular structure, the helix adamantane constitutes the stable part of the molecule, and the derivative aromatic structure with the protective group (phosphate ester or galactopyranoside) constitutes the part that is easy to be enzymatically hydrolyzed and emits light after enzymolysis. The luminescence is broken down by dioxane into two carbonyl compounds in an excited state. For example, under the action of alkaline phosphatase (AP), the phosphate group of amppd is hydrolyzed, and a phosphate group is removed to obtain a moderately stable intermediate amppd - (half-life: 2-30min). This intermediate is cleaved into a molecule of amantanone and a molecule of methyl m-oxobenzoate anion in the excited state by intramolecular electron transfer. When it returns to the ground state, it emits light with a wavelength of 470nm and lasts for several minutes. Its luminescence mechanism is shown in the following figure:
Characteristics of amppd: (1) in alkaline environment, the hydrolysis degree of non enzymatic hydrolysis of amppd is low, that is, the background is low; (2) Amppd has good thermal stability. In water with pH = 7.0, the decomposition half-life at 30 ℃ is 142h, and the activation energy is 21.5kcal/mole; (3) At pH = 9.0, the rate of enzymatic hydrolysis of amppd by AP was the fastest; At pH = 9.5, although the enzymatic hydrolysis rate was slightly lower, the signal-to-noise ratio was the lowest; (4) The enzymolysis luminescence of amppd is glow type, with wavelength of 470nm. The intensity reaches the peak at 15min, and the light signal intensity remains the same within 15-60min, with little change. Even after 12h, the correct results can be obtained; (5) Adding enhancers such as bdmq or BSA can obviously enhance the luminescence intensity of AP enzymolysis amppd, and the enhancement factor is 100-100000 times. The enhancement mechanism of enhancers is not very clear at present, and there is no precise explanation in theory. It is generally believed in the literature that the luminous intensity and detection sensitivity of amppd in moderately polarized aprotic organic solvents (such as n-butanol, dimethyl sulfoxide, etc.) are higher than that in polarized proton solutes, especially in aqueous media. If the enhancer is added to the aqueous medium, the enhancer is surrounded by the amppd molecule, and may combine with the chromophore produced by the enzymatic hydrolysis of amppd through hydrophobic or ionic interaction or both, so that the chromophore forms a stable structure. In this way, the chromophore is separated from the water molecule, thus preventing the chromophore from returning from the excited state to the ground state. Non light emission channels such as vibration relaxation release all or part of the energy in the form of thermal energy. Some natural water-soluble macromolecules such as water-soluble globulin BSA, has, etc. and artificially synthesized polyquaternary ammonium salts such as TMQ, bdmq, etc. all contain hydrophobic regions in their molecular structures, which can provide a hydrophobic microenvironment, It has the function of stabilizing the chromogenic group to enhance the luminous intensity.
CSPD and CDP star are AP enzymatic chemiluminescent substances synthesized after amppd, and their luminescent properties are better than amppd: CSPD and CDP star are more stable than amppd; The degree of non enzymatic hydrolysis is lower; The enzymolysis speed is faster, and only half of the amppd time is needed to reach the maximum optical signal; And the luminous signal is stronger and the signal-to-noise ratio is higher; CSPD and CDP star are the most ideal chemiluminescent materials for AP enzymatic hydrolysis.
The commonly used system for the application of (amantadine) - 1,2-dioxane and its derivatives to CLIA is the dioxetane / AP / en 2H ance system, that is, the antigen or antibody is labeled with alkaline phosphatase (AP), the (amantadine) - 1,2-dioxane or its derivatives are used as the luminescent substrate, and the enhancer is added to the luminescent substrate.