Nondestructive biochemical assessment of archived tissue specimens in biobank settings using endogenous fluorescence lifetime imaging

Biobanks are increasingly focused on maintaining high-quality specimens for patient-oriented research, requiring stringent quality control (QC). Preserving specimen integrity involves minimizing the time between tissue collection and storage at -80°C or lower. Traditional pathological assessment, while useful for confirming tissue content, is destructive and less commonly used. This study explores endogenous fluorescence lifetime imaging (FLIM) as a non-destructive alternative for biobank QC. Using a handheld FLIM system, 39 tumor and 10 non-tumor frozen kidney tissue samples were imaged without compromising tissue integrity. The system targeted endogenous fluorophores to distinguish cancerous from nonmalignant tissues. Pathological assessment was used to annotate the FLIM data, which was used to train a Random Forest classification model. The model achieved 87% sensitivity and 100% specificity, demonstrating FLIM's potential in enhancing biobank QC by providing label-free tissue discrimination while preserving specimen integrity.