It has long been understood that adding flexibility to structures such as buildings and bridges adds stability during very high winds or even earthquakes. Rigid buildings tend to fail, as their resistance to movement leads to a buildup of stress which can only be released through damage to the structure. In comparison, adding flexibility to a building can help dissipate any destructive energy. Of course, there needs to be a balance between design for flexibility and rigidity, as the famous Tacoma Narrows bridge failure shows.
So, does the same apply to analytical methods? More than a decade ago Malvern Instruments introduced Standard Operating Procedures (SOPs) to lock down the definition of methods used for laser diffraction particle sizing. At the time, this was a ground-breaking innovation, and has led to the widespread application of the technique within Pharmaceutical QC applications. But is fixing a method to a single set of measurement parameters the best to ensure reproducible results? The Quality by Design (QbD) approach to product development – which leads sponsors towards defining the ‘design space’ within which a product or process can vary without impacting product performance – may suggest not. So, can the flexibility of the QbD approach be extended to analytical methods?
Analytical Quality by Design
The application of QbD to analytical methods (AQbD) begins from the premise that building quality into an analytical method to ensure that it delivers the desired information every time that method is used. Just like conventional QbD, AQbD requires the risk factors associated with a method to be identified and investigated, leading the definition of method design space – the Method Operable Design Region (MODR) – within which the method yields the required results. Defining this holds out the reward of consistent, well controlled performance and will help with the transfer of the method from product development, through scale-up and into manufacture.
Malvern’s new white paper ‘Beyond SOPs – Exploring the rigor and requirements of Analytical QbD’ presents an introduction to AQbD and explores the workflow associated with its adoption. It includes data showing the practicalities of applying AQbD in the development of laser diffraction particle sizing methods. The paper also reviews instrument features that can be helpful, such as the Mastersizer 3000’s optical property optimizer (see video below) which has been released with the latest software update for the Mastersizer 3000.
If you, like us, are interested in AQbD and the benefits it offers then why not download the white paper? Alternatively, tell us about your experiences of trying to apply AQbD and the instrument features that you’ve found most useful via Malvern’s Linkedin Group. And if you secretly thought you should have been a structural engineer rather than an analytical scientist, why not try designing your own bridge to see if you can add the appropriate level of flexibility to withstand an earthquake!