Purification of IgG Using Caprylic Acid

Caprylic (octanoic) acid can be used to purify mammalian IgG from serum, plasma, ascites fluid, and hybridoma culture supernatant by precipitation of non-IgG protein () (see Note 1). Other methods have been described where caprylic acid has been used to precipitate immunoglobulin depending on the concentration used. The concentration of caprylic acid required to purify IgG varies according to species (see Subheading 3., step 2).