Pharmaceutical Technology Europe - March 2010 - (Page 15)

Measuring headspace gas concentrations and residual moisture content Technological advances and regulatory documents, such as Annex 1 of the EU Guideline for Good Manufacturing Practice, have encouraged the pharmaceutical industry to install various new technologies into their production lines. provide information regarding the remaining absolute pressure in the headspace. The benefit of this is a final quality concept that can be used as a release test — all products are being tested and individual faulty products are reliably detected. As well as being used to improve the quality of lyophilised products, the technology can also be used as an effective PAT tool. One of our clients, for example, has received authorisation to use this testing technology instead of placing their capping process into a Grade A air supply until the cap has been crimped, as requested by Annex 1 of the EU Guideline to Good Manufacturing Practice. reflection spectroscopy and is capable of handling up to 3000 vials/min. The vial containing the residual material of the lyophilisation process is exposed to a broadband light source that contains a high amount of NIR radiation. This radiation interacts with the lyophilised product and reflects the portion of radiation that has not been absorbed from the material. The lost energy along the NIR wavelength range provides a specific spectral response that enables individual chemical and physical properties to be identified. One of the properties that can be extracted is a signal that relates to a specific absorption of water molecules and scales directly to the relative water content in the lyophilisation cake. The NIR diffuse reflection is collected and correlated with a predefined model of water absorption. In turn, this model is used to predict the residual water content in unknown samples. The freeze-drying process is well known for producing unidentified, out-of-specification products when it comes to moisture content — even under strict parameter control. The above system, however, can be a useful tool for providing a final quality check. PTE Based on a contribution by Gerhard Schramm Sales Director on Head Space Analysis Technology at Wilco AG Switzerland. Dr Heino Prinz Head of PAT and Consulting at Uhlmann-VisioTec Germany. To read the full version of this article, go to: www.pharmtech.com/schramm www.wilco.com Headspace analysis Gas concentrations, such as oxygen or moisture, can be reliably detected in freeze-drying vials by guiding a wavelength modulated low-power laser beam (class 1) through the headspace. We have improved this process to enable up to 600 vials/min to be tested, with only a few laser based absorption test heads mounted on a continuous motion rotor. Head Space Analysis (HSA) technology can provide accurate measurements of the smallest oxygen levels or, by analysing moisture concentrations, NIR inspection Our NIR inspection system for determining moisture content in freeze-dried products uses NIR diffuse 1 CONTENTS 10 COMPUTER MODELLING 6 ENGINEERING TRENDS 11 A FUTURE ALTERNATIVE 7 FREEZE DRYER SELECTION 13 FREEZE DRYING BIOLOGICALS 8 FREEZE DRYER CLEANING 16 TOP TECHNOLOGIES http://www.pharmtech.com/schramm http://www.wilco.com

Table of Contents for the Digital Edition of Pharmaceutical Technology Europe - March 2010

Pharmaceutical Technology Europe - March 2010
Contents
Key Considerations when Developing a Freeze-Dried Formulation and Current Trends
Engineering Trends and Developments in Lyophilisation
Selecting a Freeze Dryer
Cleaning Freeze Dryers
Computer Modeling the Freeze Drying Process
Vacuum H2O2 Gas Sterilisation in Lyophilisers: A Future Alternative?
'Thermal Fingerprinting': A Way to Optimise Lyophilisation
Freeze Drying of Biologicals
Developing a Safe Lyophilisied Adjuvant Vaccine
Measuring Headspace/Gas Concentrations and Residual Moisture Content
Eight Latest Technologies Showcased

Pharmaceutical Technology Europe - March 2010