title: Trypsin and trypsin inhibitor bind PAMAM nanoparticles: Effect of hydrophobicity on protein-polymer conjugation.
abstract: Protein-polymer conjugates are widely used in therapeutic drug delivery. We report the bindings of trypsin (Try) and trypsin inhibitor (Tryi) with polyamidoamine (PAMAM-G4) dendrimer at physiological conditions, using thermodynamic analysis, UV-Visible and Fourier transform infrared (FTIR) spectroscopic methods. Thermodynamic parameters ΔS, ΔH and ΔG showed protein-PAMAM bindings occur via H-bonding and van der Waals contacts with trypsin inhibitor forming more stable conjugate than trypsin. PAMAM complexation induces more perturbations of trypsin inhibitor structure than trypsin with reduction of protein alpha-helix and major changes of beta-structures. The negative value of ΔG indicates spontaneous protein-polymer conjugation at room temperature.
authors.affiliation: Department of Chemistry-Biochemistry and Physics, University of Québec at Trois Rivières, C.P. 500, TR, Quebec 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 G9A 5H7, Canada. Electronic address: tajmirri@uqtr.ca.
authors.forename: H A
authors.initials: HA
authors.lastname: Tajmir-Riahi
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D050091:Dendrimers / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D053758:Nanoparticles / Q000737:chemistry*; D010179:Pancreas / Q000201:enzymology; D013329:Structure-Activity Relationship; D014357:Trypsin / Q000737:chemistry* / Q000378:metabolism; D014361:Trypsin Inhibitors / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D050091:Dendrimers; C104700:PAMAM Starburst; D014361:Trypsin Inhibitors; D014357:Trypsin
keywords: Conjugation; Dendrimer; Hydrophobicity; Spectroscopy; Thermodynamic; Trypsin; Trypsin inhibitor