title: Effect of bovine serum albumin on the functionality and structure of catanionic surfactant at air-buffer interface.
abstract: Interaction of bovine serum albumin (BSA) with the solvent spread monolayer of a catanionic surfactant, octadecyltrimethylammonium dodecylsulfate, (C18TA(+)DS(-)) at the air-buffer interface was investigated by measuring the surface pressure with time and change in surface area. Dipalmitoylphosphatidylcholine (DPPC) was used as reference. Kinetics of BSA desorption from the interface to the buffer subphase, that of C18TA(+)DS(-) and DPPC through their interaction with BSA, were also studied at different BSA concentrations (in the subphase) and surface pressures. Surface pressure (π)-area (A) isotherms (at pH = 5.4, μ = 0.01, T = 298 K) revealed that the coacervate/DPPC monolayer becomes expanded in the presence of BSA at low π while their protein bound species are released into the subphase at high π. Film morphology, studied by epifluorescence microscopy (EFM) and atomic force microscopy (AFM), reveals that the sizes of the domains of both DPPC and coacervate decrease in the presence of BSA. Presence of BSA in the coacervate and DPPC monolayer was supported from AFM data analysis.
authors.affiliation: Centre for Surface Science, Department of Chemistry, Jadavpur University, Kolkata 700 032, India.
authors.forename: Kajari
authors.initials: K
authors.lastname: Maiti
authors.affiliation: Centre for Surface Science, Department of Chemistry, Jadavpur University, Kolkata 700 032, India.
authors.forename: Subhash C
authors.initials: SC
authors.lastname: Bhattacharya
authors.affiliation: Centre for Surface Science, Department of Chemistry, Jadavpur University, Kolkata 700 032, India.
authors.forename: Satya P
authors.initials: SP
authors.lastname: Moulik
authors.affiliation: Department of Chemistry, University of North Bengal, Darjeeling 734 013, India. Electronic address: akpanda1@yahoo.com.
authors.forename: Amiya K
authors.initials: AK
authors.lastname: Panda
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D000388:Air; D000818:Animals; D002021:Buffers; D002412:Cations / Q000737:chemistry; D002417:Cattle; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D002021:Buffers; D002412:Cations; D013501:Surface-Active Agents; D015060:1,2-Dipalmitoylphosphatidylcholine; D012710:Serum Albumin, Bovine