Speaker Interview with Dr Amy Johnson

Approaches to address knowns, unknowns and known-unknowns in leachables

Ahead of Extractables and Leachables Europe 2022, we spoke to E&L expert, Dr Amy Johnson, Principal Scientist - Medical Device Testing at Smithers.

Our interview covered an exclusive preview of her presentation on 'Approaches to address knowns, unknowns and known-unknowns in leachables', as well as Dr Johnson's thoughts on the major challenges currently facing E&L professionals.



Your presentation will look at leachables – how to address knowns, unknowns and known-unknowns. Can you give us a snapshot of what delegates will hear? 

We’re all familiar with the three types of compounds in leachables studies: the “known” compounds which have an ID and are relatively straightforward to deal with using a targeted approach, the “unknown” compounds which we screen for using non-targeted approaches, and then the more tricky “known-unknown” compounds which we screen for as target compounds, but with more limited information about them compared to “known” compounds, making things less straightforward.

So I’ll be comparing the different approaches taken to addressing knowns, unknowns, and known-unknowns, and discussing ways in which we can deal with known-unknowns in leachables studies.

What do you see as the major challenges that E&L professionals in general are facing? How might that change in the near-mid future? Is there anything evolutionary or revolutionary on the horizon?

I think some of the major challenges are the continuous aims to achieve even lower AETs whilst also increasing our levels of confidence in compound identifications – constantly pushing our analytical techniques and methods to their limits. But I think that the development and implementation of automated systems for sample preparation, as well as the ever-increasing performance and capabilities of our instruments, particularly HRMS, are really making a difference to what we can achieve.

I’m also interested to see if/how ambient ionisation MS could be applied to E&L analysis – the efficiency of avoiding laborious sample preparation whilst performing a rapid analysis would vastly improve throughput in the lab.

What are you most looking forward to hearing about and discussing with your peers at E&L Europe 2022?

This will be my first ever E&L conference, so I’m really looking forward to hearing about the whole range of topics that will be presented! It will be great to have the chance to get involved in conversations with people who are experts in various fields of E&L and to be able to join in discussions about the topics presented, as well as any other topics that might come up. I’m particularly interested in where technology can take us in the future and would love to hear people’s thoughts on this!

Session 6: Analytical Chemistry

Dr Johnson will be presenting as part of the 'Analytical Chemistry' session at E&L Europe 2022 on day two of the conference. Other presentations in this session include:

  • A comparative study of Electron Spray Ionization (ESI) LC/MS versus Atmospheric Pressure Chemical ionization (APCI) LC/MS on extracts of medical devices - Philippe Verlinde PhD | Senior Scientist - Study Director, Nelson Labs Europe
  • Qualitative extractable and leachable testing using a MS/MS library - Ferran Sanchez | Market Development Manager, Pharma/CRO (MS & CE) and Aftermarket, EMEAI, SCIEX
  • Ready-to-use calibrants for extractables & leachables testing methods - Markus Obkircher | Director R&D, Merck KGaA