Acridine salt NSP-SA-NHS is a commonly used chemical reagent widely used in biochemical and molecular biology research for protein modification and coupling reactions. It can form stable ester bonds by reacting with amino groups in proteins, making it highly specific and selective. Acridine ester NSP-SA-NHS is a highly stable and sensitive chemiluminescence reagent, commonly used for labeling proteins, peptides, antibodies, nucleic acids, etc. Moreover, in an alkaline hydrogen peroxide environment, protein labeling does not require the use of enzyme catalysis to self emit light, making the operation simple. The main factors affecting the stability of acridine ester NSP-SA-NHS are as follows: 1. It is stable in acidic solutions with a pH value less than 4.8, and can be stored at room temperature for about 4 weeks with no change in its quantum yield. The freeze-dried product can be stored for more than a year at -20 ℃. 2. When the pH value of the solution is greater than 4.8, acridine ester NSP-SA-NHS and its compounds are prone to hydrolysis and decrease their stability. That is, the higher the pH value, the higher the degree of hydrolysis, and then the stability decreases. 3. The stability of acridine ester NSP-SA-NHS is greatly affected by temperature. The higher the temperature, the higher the degree of hydrolysis, and the lower the stability. The hydrolysis process is a dark reaction process that does not emit light