The EDC coupling method results in the formation of a thioester bond that is cleavable by reducing agents, such as dithiothreitol or glutathione, which are present in the body. This cleavage mechanism allows for the controlled release of the aspirin from the conjugate, making it an effective prodrug for targeted drug delivery. Our study investigated the metabolism and release profile of an aspirin-cysteine conjugate in simulated intestinal fluid (SIF) and phosphate-buffered saline (PBS). By employing SIF as a model of the intestinal environment and utilizing the FeCl3 assay, we were able to mimic and monitor the metabolic process of aspirin in a manner relevant to the body The results of our study demonstrated that the aspirin-cysteine conjugate exhibited an exponential release pattern compared to the relatively linear release profile of aspirin alone. This can be attributed to the prodrug nature of the conjugate, which requires hydrolysis to release the active aspirin moiety. The initial slower release rate of the conjugate may be due to the time required for the hydrolysis reaction to occur. However, once the hydrolysis process is initiated, the release of aspirin from the conjugate increases rapidly, resulting in an exponential release profile. Furthermore, the aspirin-cysteine conjugate showed a significantly longer half-life compared to aspirin alone when tested in PBS. The calculated half-life of the conjugate was 239.1 hours, indicating its relative stability under these conditions. This prolonged half-life suggests that the conjugate has the potential for sustained release applications or as a long-acting anti-inflammatory agent. Overall, our findings highlight the effectiveness of the aspirin-cysteine conjugate in providing prolonged and sustained release of aspirin in the body. The conjugate's ability to exhibit an exponential release profile and its extended half-life make it a promising candidate for therapeutic applications requiring controlled and prolonged drug delivery. Further investigations are warranted to explore the pharmacokinetics and pharmacodynamics of the conjugate in vivo to fully assess its potential as a therapeutic agent.