102 A new diagnostic tool has been developed to differentiate between colitis and colorectal cancer, two conditions that are often difficult to distinguish in their early stages. Scientists have designed a fluorescent probe that targets carboxylesterase 2 (CES2), an enzyme with altered expression in colorectal cancer. The probe, known as DBF-CES2, offers a more precise and non-invasive method for early detection. The findings were published in the journal Sensors and Actuators B: Chemical. Colorectal cancer remains one of the most commonly diagnosed cancers, with high mortality rates due to late detection. Inflammatory bowel diseases, including colitis, are known to increase the risk of colorectal cancer by promoting chronic inflammation in the digestive tract. Distinguishing between colitis and cancer is critical, yet current diagnostic methods rely heavily on invasive procedures such as biopsies and endoscopies. The newly developed probe, DBF-CES2, functions by detecting CES2, an enzyme with increased activity in colorectal cancer cells compared to normal and inflamed tissues. Upon interaction with CES2, the probe undergoes a chemical reaction that triggers a red fluorescent signal, allowing researchers to identify cancerous cells with greater accuracy. The probe has demonstrated a high level of sensitivity, capable of detecting enzyme concentrations as low as 0.70 ng/mL. Laboratory experiments using human colorectal cancer cell lines have confirmed that DBF-CES2 selectively identifies cancer cells based on their elevated CES2 activity. Fluorescent imaging of these cells showed a marked difference in signal intensity between cancerous, normal, and inflamed tissues, suggesting that this technique could significantly improve early diagnosis. Further testing in mice has reinforced the probe’s potential. Researchers induced colitis in a group of mice and compared their CES2 activity levels to those in mice with colorectal cancer. Imaging results revealed that CES2 expression was significantly higher in cancerous tissues and lower in inflamed tissues, validating the probe’s ability to distinguish between the two conditions. Additionally, the probe was used to assess the therapeutic effects of two different treatments, demonstrating its potential use in monitoring disease progression and response to therapy. Unlike conventional diagnostic methods, DBF-CES2 offers a non-invasive approach with real-time imaging capabilities. Fluorescence-based techniques have been increasingly explored for medical diagnostics due to their ability to provide immediate results without the need for complex sample processing. The large Stokes shift of 167 nm observed in this probe ensures minimal interference from background fluorescence, improving its reliability in clinical settings. The development of this probe marks a significant advancement in the field of cancer diagnostics. The ability to differentiate between colitis and colorectal cancer with a simple imaging test could reduce the need for unnecessary invasive procedures and enable earlier intervention. The research team behind the study hopes to move towards clinical trials, with the ultimate goal of integrating this technology into routine medical practice. As cases of colorectal cancer continue to rise globally, tools like DBF-CES2 could play a crucial role in improving early detection rates. With further validation, this probe may soon become an essential component in the diagnostic process, offering patients a faster and less invasive path to treatment.