Expi293 Met (–) Expression Medium is a cGMP-manufactured, chemically defined, serum-free, protein-free, animal origin-free, methionine-free medium for growth and transfection of Expi293F cells. The medium is part of the Expi293 platform for rapid, high-yield transient protein expression from mammalian HEK293 cells. It is designed for use in combination with the ExpiFectamine 293 Met (–) Transfection Kit for applications where labelling of methionine residues in proteins is desired. Note: the medium will not support cell growth or expression unless supplemented with methionine.

Expi293 Met (–) Expression Medium features include:
• Supports growth of suspension 293 cultures to densities of over 1.5 x 10⁷ cells/mL
• Equivalent performance to Expi293 Expression Medium (Cat. No. A1435101)
• Does not contain methionine
• Does not contain phenol red
• Formulated with GlutaMAX I Supplement
• Supplementation with methionine required

L-methionine (methyl-¹³C) and L-selenomethionine labeling reagents are available separately.