RPMI

RPMI, named for Roswell Park Memorial Institute, is a widely used family of mammalian cell culture media developed for in vitro growth of hematopoietic and lymphoid cells. The classic formulation, RPMI 1640, was created in the 1960s at Roswell Park Memorial Institute in Buffalo, New York, by Moore and colleagues. The medium is a buffered, salt-based solution that contains amino acids, vitamins, inorganic salts, and a carbohydrate source, with sodium bicarbonate as the buffering system and phenol red as a pH indicator. It is designed for use in incubators with carbon dioxide, and is commonly used with supplements to support cell growth.

RPMI 1640 is typically prepared with additional components such as L-glutamine (or L-glutamine–containing variants) and fetal bovine serum, and is frequently enriched with antibiotics to reduce microbial contamination. The choice of serum concentration and supplements can vary by cell type and experimental needs. The medium is suitable for a wide range of cell lines, particularly lymphoid and hematopoietic cells, but with appropriate adjustments it can support other mammalian cells as well.

Variants of RPMI 1640 exist, including formulations with or without L-glutamine and with different buffering additives such as HEPES. These variants accommodate different culture requirements and CO2 conditions. Handling of RPMI should follow standard sterile techniques, with storage at 2–8°C for unopened bottles and careful monitoring for contamination once used. It remains a staple reference medium in immunology and cell biology laboratories.