title: Calculation of injection forces for highly concentrated protein solutions.
abstract: Protein solutions often manifest a high viscosity at high solution concentrations, thus impairing injectability. Accordingly, accurate prediction of the injection force based on solution viscosity can greatly support protein formulation and device development. In this study, the shear-dependent viscosity of three concentrated protein solutions is reported, and calculated injection forces obtained by two different mathematical models are compared against measured values. The results show that accurate determination of the needle dimensions and the shear-thinning behavior of the protein solutions is vital for injection force prediction. Additionally, one model delivered more accurate results, particularly for solutions with prominent shear-thinning behavior.
authors.affiliation: Biologics Process Research and Development, Novartis Pharma AG, 4002 Basel, Switzerland.
authors.forename: Ingo
authors.initials: I
authors.lastname: Fischer
authors.affiliation: Biologics Process Research and Development, Novartis Pharma AG, 4002 Basel, Switzerland.
authors.forename: Astrid
authors.initials: A
authors.lastname: Schmidt
authors.affiliation: Pharmaceutical and Analytical Development, Novartis Pharma AG, 4002 Basel, Switzerland.
authors.forename: Andrew
authors.initials: A
authors.lastname: Bryant
authors.affiliation: Biologics Process Research and Development, Novartis Pharma AG, 4002 Basel, Switzerland. Electronic address: ahmed.besheer@novartis.com.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Besheer
mesh_terms: D002626:Chemistry, Pharmaceutical; D007267:Injections; D055595:Mechanical Phenomena; D008962:Models, Theoretical; D009339:Needles; D011506:Proteins / Q000737:chemistry*; D012212:Rheology; D012996:Solutions / Q000737:chemistry*; D014057:Tomography, X-Ray Computed; D014783:Viscosity
chemical_list: D011506:Proteins; D012996:Solutions
keywords: High concentration protein solution; Injectability; Injection force; Viscosity