Evidence-based standardization of infectious disease biobanking: aligning specimen preservation and clinical metadata with in vitro diagnostic clinical trials requirements.

BACKGROUND: Biobanks accelerate in vitro diagnostic (IVD) clinical trials by providing annotated, quality-controlled biospecimens. However, a persistent translational gap remains because the specific requirements of IVD trials-including sample matrices, preservation protocols, aliquot volumes, freeze-thaw tolerability, and clinical metadata-have not been systematically characterized. This study aims to establish an evidence-based framework to align infectious disease biobanking operations with regulatory-grade IVD trial demands by systematically characterizing the specimen preservation parameters and clinical metadata requirements of IVD trials. METHODS: We retrospectively analyzed 140 infectious disease IVD trials (covering HIV/AIDS, COVID-19, viral hepatitis, and tuberculosis) conducted at a major Chinese infectious disease center between 2018 and 2025. Using a standardized extraction protocol, we systematically evaluated specimen preservation parameters (sample type, aliquot volume, storage temperature, duration, and freeze-thaw cycles), clinical metadata elements (universal and disease-specific), and control sample requirements. RESULTS: Serum/plasma was the primary matrix (75.7% of trials), followed by whole blood (20.0%), sputum (13.6%), and swabs (10.7%). Predominant aliquot volumes were 0.5-1.0 mL for serum/plasma (52% of trials), 0.1-0.5 mL for whole blood (66%), and 2.0-3.0 mL for sputum (50%). Most trials preferred frozen specimens (48.6% exclusively frozen; 37.9% accepting both). For short-term preservation (2 °C-8 °C), a 7-day window was acceptable in 56% of serum/plasma protocols; for long-term preservation, -70 °C was required for 80% of serum/plasma and 100% of sputum samples. Strict freeze-thaw avoidance was mandated in 64% of serum/plasma, 72% of whole blood, and 60% of swab protocols. Core metadata (sample type and clinical diagnosis) were universally recorded (100%), whereas disease-specific laboratory parameters and control sample showed marked variation across disease categories. CONCLUSION: This single-center analysis offers preliminary evidence for a framework to standardize infectious disease biobanking practices tailored to IVD clinical trials. Implementation of the proposed preservation guidelines and tiered metadata framework, including standardized aliquot volumes, temperature-dependent storage protocols, strict freeze-thaw limitations, and strategic accrual of diverse control specimens, has the potential to optimize specimen utility, accelerate diagnostic development, and strengthen outbreak preparedness. However, external validation through multicenter studies is needed before these recommendations can be generalized to other settings.