Strengthening a Weak Link in QC Microbial Testing (Part II)

POSTED BY Rapid Micro Biosystems | 5 minute read

By Mark Newton and David L. Jones

Microbial enumeration testing in the pharmaceutical QC lab is based around well proven traditional manual methods that have changed little since the creation of the first pharmacopeia. These manual processes rely heavily on the training, expertise and judgment of the individuals who perform them. Improvements have been made to the processes to minimize variation such as: use of commercial media, validated incubators, verification signatures and electronic batch records; however, the ability to accurately see and enumerate colonies, then accurately record the information to paper or electronic system, is still a weak link in the forensic data trail.

In this four-part series, we will explore the unprecedented capabilities of automated plate counting: consistent counting, time savings and reduced fatigue for analysts, and automated capturing of complete, original data for review, monitoring and trending analysis. Along the way, we will also suggest key considerations for QC labs evolving from manual plate counts to automation.

Advantages of Digitalization

The key to mitigating microbiological risks in quality control testing, in addition to increasing efficiency and reducing ergonomic issues, can be found in the use of digital systems. Digital systems offer hands-free, consistent analysis of plates, the capability to save an image of the plate at the time of analysis, and the ability to save a complete record of testing whether passing, failing, or invalid.

Here are just some of the many advantages realized by microbiological laboratories that move forward with digital plate reading and analysis:

Twelve Advantages of Electronic Plate Counts with Images

  • Faster plate counting
  • Consistent counting using validated algorithms
  • Changes have date/time stamp that permits scope of any issues to be defined during investigation
  • Contemporaneous metadata – no delays in capture, test analyst cannot modify date/time 
  • Ability to digitally review original plate image in the future
  • Ability to review changes in count made after original automated count
  • Avoids analyst's visual fatigue
  • Adds metadata not present in paper records, including:
    • Correct date/time of actions
    • Who performed each action
    • Audit trail entries
    • Protected clock for audit trail entries
  • Assay results available for upload to LIMS/ELN - no transcription errors
  • Greater ability to discover data integrity issues through automated searches of timestamps and audit trails, resolving questions such as:
    • "Too good to be true" data
    • Can't do that much work in a day
    • Can't perform step that quickly
    • How many times do we adjust result values?
    • How large is the adjustment from original to adjusted value?
    • Does one lab make manual adjustments more often than another lab?
  • Images (and count adjustments) preserved in electronic records for trending and development of custom reports
  • Superior access controls – only authorized people can generate regulated data and reports, and the system admin can be independent of people creating test data

In the next post of our four-part series, we will address some key considerations for users of digital plate count systems. Look for it soon!

Mark Newton is an associate senior quality assurance consultant at Eli Lilly and Company. David L. Jones is director of marketing and industry affairs at Rapid Micro Biosystems. This content previously appeared in edited form in the March 2022 issue of Cleanroom Technology.

Part I  |  Part II  Part III |  Part IV