Drainage and critical thickness of foam films from mixed solutions of bovine serum albumin and n-dodecyl-β-D-maltoside

► Drainage coefficient α and critical thickness hcr of BSA/C12G2 films are measured. ► The BSA:C12G2 (1:7.5, 1:50) films thin faster than those with pure BSA. ► The film radius and BSA/C12G2 ratio do not change much α in the first spot area. ► hcr values of BSA and mixed films in the spots areas do not differ significantly. ► A big difference is found in h values for the film periphery and other areas.