My project utilized a lipid monolayer at a water-fluorinated oil interface as a biomimetic cell membrane model. Lipid ternary mixtures are used to mimic cellular membrane heterogeneity, and to understand the role of phase separation. Polystyrene microparticles are introduced to study their interactions, and then located using confocal and side-view microscope. This study deepens understanding of polymer microparticles interactions with membranes, aiming to minimize cytotoxicity and boost therapeutic efficacy.