Integration of an In-line Dose Verification into a Micro-dosing System for Fine Powders
Xiaolong Chen1, Karlheinz Seyfang1, Hartwig Steckel2
1 Harro Hoefliger Verpackungsmaschinen GmbH, Allmersbach im Tal, Germany
Corresponding author: Prof. Dr. Hartwig Steckel, Pharmazeutisches Institut, Abteilung Pharmazeutische Technologie und Biopharmazie, Christian-Albrechts-Universität, Grasweg 9a, 24118 Kiel, Germany, e-mail: email@example.com
In a former study a micro-dosing system for fine powder using a vibrating capillary was developed. The parameters, for instance, the amplitude, the frequency and the ratio of capillary orifice to particles size were studied in an experimental design. This paper reviewed the design issues during the development of the dosing system. The influence of the wall surface finish in capillaries on the flow rate was studied. A highly sensitive electric capacitance sensor was integrated as a new in-line non-contact control in the micro-dosing system for fine powder. The dosing results were compared using the check weighing method and a 3 % relative standard deviation was achieved with a mean dosed value of about 5 mg. The results with a variety of pharmaceutical powders are considered promising.
Key words Capacitance sensor • Capillary • Micro-dosing • Powder properties • Vibration
pharmind 2011, Nr. 8, Seite 1508