APS-5

Product name	APS-5
Synonym	[(4-Chlorophenyl)thio](10-methyl-9(10H)-acridinylidene)-methanol1-(dihydrogenphosphate)disodiumsalt(1:Chemicalbook2);LumigenAPS5;APS-5;Disodium[(4-chlorophenyl)sulfanyl](10-methyl-9(10H)-acridinylidene)methylphosphate
	193884-53-6
Appearance	White to pale yellow solid
Purity	≥98%
MF	C21H18ClNNaO4PS
MW	469.85
Related categories	Chemiluminescent substrates; biological buffers
Transport Information	Not dangerous goods
Product photo
Product Manager Email:	jessie@coreychem.com

Frequently Asked Questions

Question 1:What are the basic physical properties of APS-5（CAS NO.: 193884-53-6）?

APS-5 is typically a white to pale yellow powder. Its molecular formula is C₂₁H₁₈ClNNaO₄PS, and its molecular weight is 469.85. The product is readily soluble in water and in pH-neutral or weakly alkaline buffers, but is sparingly soluble in common organic solvents. It is relatively stable in the solid state, but its aqueous solution is prone to hydrolysis and should not be stored for prolonged periods. The recommended storage conditions are typically at –20 °C, protected from light and moisture, in a sealed, dry container.

Question 2:In terms of its application, what are the key features of this product?

The core application of this product is as a chemiluminescent substrate for immunoassay systems using alkaline phosphatase (ALP) as a marker. Its most significant value lies in the 9,10-dihydroacridine group within its molecular structure, which, under the action of ALP, rapidly releases photons, producing sustained, stable and high-intensity chemiluminescence. This product is characterised by high sensitivity, high luminescence intensity and a long luminescence duration, making it suitable for applications such as ELISA assays, phosphatase activity assays and gene chip research.

Question 3:What role does this product play in chemiluminescence detection?

It is a key reagent in chemiluminescent immunoassays. Under the catalysis of alkaline phosphatase (ALP), the 9,10-dihydroacridine group in the structure of APS-5 reacts, rapidly releasing photons with a peak emission wavelength of approximately 430–450 nm. The number of photons released is directly proportional to the concentration of ALP in the solution; consequently, it can be used for the quantitative detection of antigens or antibodies. The reaction reaches a plateau within a few seconds, and this plateau persists for a long duration, making it highly suitable for ultramicroassays.

Question 4:How should this product be stored and handled?

As the aqueous solution of APS-5 is prone to hydrolysis, particular care must be taken during storage and handling. It is recommended that the solid powder be stored at –20 °C in a light-protected, moisture-proof, sealed and dry container, where it will remain stable for over two years. Once prepared as a liquid, the reagent should be allowed to equilibrate to room temperature (22–35 °C) before use; under no circumstances should it be exposed to strong light, as even brief exposure can cause a significant increase in background signal. Once prepared as a liquid, it must not be frozen; it is recommended that it be used immediately after preparation.

Question 5:How does the concentration or formulation of this product affect its actual performance?

In practical use, APS-5 is typically prepared as a working solution, and the type of surfactant in the formulation has a significant impact on signal stability. Studies have shown that formulations containing IGEPAL, TRITON and BRIJ surfactants exhibit signal loss of less than 10 per cent after 15 months’ storage at 4 °C, demonstrating superior stability to formulations containing TWEEN® 20. Furthermore, the pH of the working solution has a significant impact on assay performance; APS-5 performs best under high pH conditions of 9.5–10.0. Prior to use, ensure that the microplates, reagents and buffers are all at a stable room temperature (20–25 °C) to guarantee the reproducibility of the assay results.