title: About the albumin structure in solution and related electro-spinnability issues.
abstract: In this work, we study the relationship between the shape and form of bovine serum albumin (BSA) protein in different solutions and their ability to form electrospun nanofibers. Small-angle X-ray scattering (SAXS) of the BSA in a water environment, in a 2,2,2-trifluoroethanol (TFE) environment, and in a TFE/beta-mercaptoethanol (beta-ME) environment demonstrated an unfolding pathway; folded, partially unfolded and unfolded states of the protein, respectively. The scattering plot of BSA in water is characterized by a strong peak, thereby describing a solution of densely packaged globules. The scattering of BSA in TFE is attributed to a chain with compact folded-domains along its length, where the scattering of BSA in a mixture of TFE and beta-ME suggests that the protein molecule adopts a freely coiled conformation in this solution. The zeta potential for both solutions of BSA in TFE was found to have an almost zero net charge, while the BSA solution in the water was highly negatively charged. This unfolding between three conformational states was correlated with the changes in electro-spinnability. Results show that the unfolded BSA is the only spinnable solution, producing long and continuous fibers with good mechanical stability.
authors.affiliation: Russell Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa 32000, Israel.
authors.forename: Omri
authors.initials: O
authors.lastname: Regev
authors.forename: Rafail
authors.initials: R
authors.lastname: Khalfin
authors.forename: Eyal
authors.initials: E
authors.lastname: Zussman
authors.forename: Yachin
authors.initials: Y
authors.lastname: Cohen
mesh_terms: D000818:Animals; D002417:Cattle; D008623:Mercaptoethanol / Q000737:chemistry; D057139:Nanofibers / Q000737:chemistry*; D019163:Reducing Agents / Q000737:chemistry; D053838:Scattering, Small Angle; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012996:Solutions; D014270:Trifluoroethanol / Q000737:chemistry; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D019163:Reducing Agents; D012996:Solutions; D014867:Water; D012710:Serum Albumin, Bovine; D008623:Mercaptoethanol; D014270:Trifluoroethanol