Project Summary/Abstract Many biological analytes of interest to both clinical oncologists and cancer researchers are unstable when the unfixed biospecimens in which they reside are exposed to thawed conditions. For example, American Society of Clinical Oncology / College of American Pathologists guidelines state that the post-excision-up-to-fixation exposure time span for tissues collected for clinical HER2 testing in breast cancer must be less than 1 hour. For blood plasma/serum and many types of tissue specimens that are to be frozen, the proper cold storage temperature is well below the common laboratory freezer temperature of -20 °C. For this and many other reasons, every year improprieties and inconsistencies in pre-analytical sample handling and storage generate unacceptably large numbers of costly false leads in biomedical research. Unsurprisingly, experts in the field agree that this problem must be minimized immediately. Currently there are few tools and not so much as one widely accepted approach by which to implement evidence-based tracking of biospecimen exposure to thawed conditions. In practice, it is actually quite rare for biomedical researchers to employ any evidence-based QA/QC tools at all—which suggests that easy-to-use, individual aliquot-level thawed-state indicators could have a major impact on improving biospecimen quality tracking and therefore actual biospecimen quality. In 2022, the PI’s lab was awarded an R21 grant through the NCI’s IMAT program to pursue development of the kinetically unique, autocatalytic, color-changing permanganate/oxalate reaction in melting point-depressed aqueous solvents as simple (i.e., user friendly), inexpensive, visual trackers of biospecimen exposure to inappropriately warm conditions, including temperature thresholds as low as -18 °C, -37 °C and -67 °C. The chemistry for 14 targeted time-temperature indicators (TTIs) has been successfully developed. Under this proposed project, the PI’s lab seeks to maximiz