title: Protein conjugation with PAMAM nanoparticles: Microscopic and thermodynamic analysis.
abstract: PAMAM dendrimers form strong protein conjugates that are used in drug delivery systems. We report the thermodynamic and binding analysis of polyamidoamine (PAMAM-G4) conjugation with human serum albumin (HSA), bovine serum albumin (BSA) and milk beta-lactoglobulin (b-LG) in aqueous solution at physiological pH. Hydrophobicity played a major role in PAMAM-protein interactions with more hydrophobic b-LG forming stronger polymer-protein conjugates. Thermodynamic parameters showed PAMAM-protein bindings occur via hydrophobic and H-bonding contacts for b-LG, while van der waals and H-bonding interactions prevail in HSA and BSA-polymer conjugates. The protein loading efficacy was 45-55%. PAMAM complexation induced major alterations of protein conformation. TEM images show major polymer morphological changes upon protein conjugation.
authors.affiliation: Department of Chemistry-Biochemistry and Physics, University of Québec at Trois-Rivières, C. P. 500, TR (Quebec) Canada G9A 5H7, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Chanphai
authors.affiliation: Department of Chemistry-Biochemistry and Physics, University of Québec at Trois-Rivières, C. P. 500, TR (Quebec) Canada G9A 5H7, Canada.
authors.forename: E
authors.initials: E
authors.lastname: Froehlich
authors.affiliation: Department of Chemistry-Biochemistry and Physics, University of Québec at Trois-Rivières, C. P. 500, TR (Quebec) Canada G9A 5H7, Canada.
authors.forename: J S
authors.initials: JS
authors.lastname: Mandeville
authors.affiliation: Department of Chemistry-Biochemistry and Physics, University of Québec at Trois-Rivières, C. P. 500, TR (Quebec) Canada G9A 5H7, Canada. Electronic address: tajmirri@uqtr.ca.
authors.forename: H A
authors.initials: HA
authors.lastname: Tajmir-Riahi
mesh_terms: D000818:Animals; D002417:Cattle; D050091:Dendrimers / Q000737:chemistry*; D016503:Drug Delivery Systems; D006801:Humans; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D007782:Lactoglobulins / Q000737:chemistry; D008853:Microscopy; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D011485:Protein Binding; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*; D012709:Serum Albumin / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013816:Thermodynamics
chemical_list: D050091:Dendrimers; D007782:Lactoglobulins; C104700:PAMAM Starburst; D011108:Polymers; D011506:Proteins; D012709:Serum Albumin
keywords: Conjugation; Dendrimer; Hydrophobicity; Protein; Spectroscopy; TEM; Thermodynamic