Injectability Evaluation: An Open Issue

摘要: The current work aimed to propose a system of scoring rationalize and support the selection optimal diameter length needles. Four formulations at different viscosity needles ranging from 21 26 G 16 40 mm were used. Plunger-stopper breakloose force, maximum force (F max), dynamic glide measured by texture analyzer crosshead speed 1 mm/s. Testing was carried out into air or human subcutaneous tissue. manual injectability highest product assessed ten evaluators. comparison panel test score quantitative measurements forces permitted given needle-syringe-formulation keeping also in consideration pressure created space muscles injection site. In particular, following relationship drawn: F max up 250 mPa, practically impossible; 160 very difficult; 125–160 mPa range, feasible, though with some difficulty; when values lower 125 mPa, went smoothly. On basis these preliminary data, is proposed needles,