Biospecimen Collection Protocol
Creative Bioarray
Abstract
A wide variety of specimen types may be collected for storage, depending on availability and study goals, such as tissues that from autopsy and transplant, cell lines, and so on.
Steps
Serum. Coagulate whole blood at room temperature (20-25°C) for 20-30 min; 1,000 x g at room temperature for 10 min; then collect supernatant, or optionally use a serum separator. If the sample is hyperlipidemic, first centrifuge at 2-8°C 10,000 x g for 10 min to separate out the lower serum layer.* Plasma. Choose citric acid or EDTA as anticoagulant according to the requirements. If heparin is chosen as the anticoagulant, it is recommended that no more than 10 IU of heparin per ml of blood be used (too high a dosage of heparin may result in high values for some assays). Within 30 min after collection of anticoagulated whole blood, the plasma is separated and collected by centrifugation at 10,000 x g at 4°C for 10 min. If the sample is hyperlipidemic, first centrifuge at 2-8°C at 10,000 x g for 10 min to separate the lower plasma layer.
- Tissue samples. Specimens are rapidly frozen in liquid nitrogen for storage after removal. Keep the specimens at 2-8°C even after thawing. Add an amount of buffer containing protease inhibitors and homogenize the specimens by hand or with a homogenizer. Centrifuge for about 20 min (2000-3000 rpm) and carefully collect the supernatant. If precipitate is present during storage, the sample should be centrifuged again to remove the precipitate before the assay. 16,000 x g centrifugation for 5 min is recommended.
