Streck Cell Preservative is an easy-to-use liquid preservative that maintains cellular antigen expression, including cluster of differentiation (CD) markers of biological samples for up to 7 days prior to analysis by flow cytometry. It preserves peripheral and cord blood samples, surgical tissue samples, bone marrow and fine needle aspirates. Streck Cell Preservative allows for the batching of samples prior to testing, optimizing laboratory workflow. In addition, it eliminates the need to immediately process or freeze samples and allows for convenient transportation from the collection site to a centralized testing location or reference lab for analysis.