Drainage and deformation of the intervening film can arguably represent the dynamic nature of colliding soft matters. The development of an interaction force analysis between soft interfaces helps to probe the drop deformation and the interfacial properties. Based on the SRYL model, the fluid flow inside the droplet and the convection-diffusion of the surfactant at the oil-water interface is coupled to model the distribution of a non-ionic surfactant (Span80) during drop deformation using AFM. This study quantifies the in situ interfacial concentration with a trace amount of surfactant at the interface and indicates its effect on the interaction forces between two immersed oil droplets in an aqueous solution.