Standard protocol for tumor tissue is sequential freezing of tumor collected within 30 to 60 minutes of surgical resection and stored in vapor phase of liquid nitrogen at a temperature of -196oC. Fat and necrotic areas are avoided.
Protocol for EDTA blood and its derivatives involves collecting blood into 10ml EDTA vial and processing within 4 hours into plasma and buffy coat fractions and stored in vapor phase of liquid nitrogen at -196oC.