Merck, SAE0073-25G, Saponin

Sigma-Aldrich saponin is a nonionic surfactant preparation used in biological assays that require controlled access to intracellular targets. Its membrane-interacting properties support permeabilization of fixed cells for intracellular antibody staining, enabling reagents to reach epitopes beyond the plasma membrane. In cell-based protocols, saponin concentration, incubation duration, fixation chemistry and wash buffer composition determine the balance between intracellular accessibility and retention of cellular structures. Use a protocol validated for the specific cell type and antigen, and keep permeabilizing components in appropriate wash steps when continuous access is required. Saponin can also support membrane-related biochemical experiments in which surfactant effects are part of the experimental design. This research reagent is not a ready-to-use staining kit, antigen-specific antibody or sterile cell culture supplement. The 25 g bottle supplies a solid preparation for laboratory formulation; solutions require controlled weighing, suitable solvent selection and documented preparation conditions.