RPMI 1640 with 25mM HEPES is a specially developed cell culture medium that combines the proven advantages of the classic RPMI 1640 medium with the additional buffering capacity of HEPES. This medium provides a stable and controlled environment for the growth and proliferation of a variety of human and animal cells, especially under conditions with fluctuating CO₂ levels. It is ideal for the cultivation of lymphocytes, hybridoma cells and various suspension cells.