title: Preformulation Characterization, Stabilization, and Formulation Design for the Acrylodan-Labeled Glucose-Binding Protein SM4-AC.
abstract: This study describes the physicochemical characterization, stabilization, and formulation design of SM4-AC, an acrylodan-labeled glucose/galactose-binding protein for use in a continuous glucose monitoring device. The physical stability profile of SM4-AC as a function of pH and temperature was monitored using a combination of biophysical techniques and the resulting physical stability profile was visualized using an empirical phase diagram. Forced degradation chemical stability studies (Asn deamidation, Met oxidation) of SM4-AC were performed using a combination of capillary isoelectric focusing, peptide mapping, and reversed-phase HPLC. Differential scanning fluorimetry was then employed to screen various pharmaceutical excipients for their ability to physically stabilize SM4-AC. An optimized formulation of 20% sucrose and 2.5 mM calcium chloride in 10 mM MES buffer, 150 mM NaCl at pH 6.0 increased the conformational stability of SM4-AC by 15°C. Accelerated and real-time stability studies were setup to compare the SM4-AC protein's physicochemical stability and glucose-binding activity in 2 formulations for up to 12 months. SM4-AC in an optimized formulation (vs the original formulation) showed improved physical stability, and similar chemical stability and glucose binding activity profiles during storage up to 52 weeks at various temperatures.
authors.affiliation: Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas 66047.
authors.forename: Neha
authors.initials: N
authors.lastname: Sahni
authors.affiliation: Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas 66047.
authors.forename: Rajoshi
authors.initials: R
authors.lastname: Chaudhuri
authors.affiliation: Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas 66047.
authors.forename: John M
authors.initials: JM
authors.lastname: Hickey
authors.affiliation: Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas 66047.
authors.forename: Prakash
authors.initials: P
authors.lastname: Manikwar
authors.affiliation: BD Medical-Diabetes Care, Andover, Massachusetts 01810.
authors.forename: Ajit
authors.initials: A
authors.lastname: D'Souza
authors.affiliation: BD Medical-Diabetes Care, Andover, Massachusetts 01810.
authors.forename: Andrew
authors.initials: A
authors.lastname: Metters
authors.affiliation: Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas 66047.
authors.forename: Sangeeta B
authors.initials: SB
authors.lastname: Joshi
authors.affiliation: Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas 66047.
authors.forename: C Russell
authors.initials: CR
authors.lastname: Middaugh
authors.affiliation: Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas 66047. Electronic address: volkin@ku.edu.
authors.forename: David B
authors.initials: DB
authors.lastname: Volkin
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D002942:Circular Dichroism / Q000379:methods; D004339:Drug Compounding / Q000379:methods*; D015195:Drug Design; D004355:Drug Stability; D005947:Glucose / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding / Q000502:physiology
chemical_list: C038518:acrylodan; D015081:2-Naphthylamine; D005947:Glucose
keywords: acrylodan fluorescence; excipients; glucose binding; high-throughput fluorescence assay; physicochemical characterization; preformulation; stabilization