The Stability of Palmitic Acid Monolayers

Sea spray aerosols, naturally-generated aerosols originating from the sea surface microlayer, affect the climate in a myriad of ways. To study the stability of the organic coatings on sea spray aerosols, palmitic acid monolayers served as a model system and equilibrium surface pressure values were measured on various subphase environments. Palmitic acid monolayers on lower pH subphases experienced the same equilibrium surface pressure, whereas a high pH subphase resulted in a significantly larger equilibrium surface pressure due to a desorption mechanism. The addition of 100 mM NaCl was found to improve the monolayer stability at each subphase pH level. In addition, a separate set of experiments focused on the effect of varying the CaCl2 concentration of the subphase. Low CaCl2 concentrations enhanced monolayer stability, while higher concentrations reduced stability. The results suggest that multiple factors of the marine and atmospheric environment are important to determining the stability of the organic films on sea spray aerosols, and hence the lifetime through which seas spray aerosols can impact the climate. Overall, information on the stability of palmitic acid monolayers can be applied to sea spray aerosols and provide some insight into the broader biological contexts of palmitic acid.Center for Aerosol Impacts on Climate and Environment (CAICE)National Science Foundation(NSF) Grant CHE1305427A one-year embargo was granted for this item.Academic Major: Biochemistr