title: Characterization of Folic Acid and Poly(amidoamine) Dendrimer Interactions with Folate Binding Protein: A Force-Pulling Study.
abstract: Atomic force microscopy force-pulling experiments have been used to measure the binding forces between folic acid (FA) conjugated poly(amidoamine) (PAMAM) dendrimers and folate binding protein (FBP). The generation 5 (G5) PAMAM conjugates contained an average of 2.7, 4.7, and 7.2 FA per dendrimer. The most probable rupture force was measured to be 83, 201, and 189 pN for G5-FA2.7, G5-FA4.7, and G5-FA7.2, respectively. Folic acid blocking experiments for G5-FA7.2 reduced the frequency of successful binding events and increased the magnitude of the average rupture force to 274 pN. The force data are interpreted as arising from a network of van der Waals and electrostatic interactions that form between FBP and G5 PAMAM dendrimer, resulting in a binding strength far greater than that expected for an interaction between FA and FBP alone.
authors.forename: Pascale R
authors.initials: PR
authors.lastname: Leroueil
authors.affiliation: Department of Chemistry, Xavier University , New Orleans, Louisiana 70125, United States.
authors.forename: Stassi
authors.initials: S
authors.lastname: DiMaggio
authors.affiliation: Department of Chemistry & Biochemistry, Calvin College , Grand Rapids, Michigan 49546, United States.
authors.forename: Abigail N
authors.initials: AN
authors.lastname: Leistra
authors.affiliation: Physical and Life Sciences Division, Lawrence Livermore National Laboratory , Livermore, California 94550, United States.
authors.forename: Craig D
authors.initials: CD
authors.lastname: Blanchette
authors.affiliation: Physical and Life Sciences Division, Lawrence Livermore National Laboratory , Livermore, California 94550, United States.
authors.forename: Christine
authors.initials: C
authors.lastname: Orme
authors.affiliation: Department of Chemistry & Biochemistry, Calvin College , Grand Rapids, Michigan 49546, United States.
authors.forename: Kumar
authors.initials: K
authors.lastname: Sinniah
authors.forename: Bradford G
authors.initials: BG
authors.lastname: Orr
authors.forename: Mark M
authors.initials: MM
authors.lastname: Banaszak Holl
mesh_terms: D002352:Carrier Proteins / Q000737:chemistry*; D050091:Dendrimers / Q000737:chemistry*; D005492:Folic Acid / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D055672:Static Electricity
chemical_list: D002352:Carrier Proteins; D050091:Dendrimers; C104700:PAMAM Starburst; D005492:Folic Acid