Immediate evidence capture and preservation

When an injection-sequence deviation is identified, secure the instrument system and preserve original electronic records immediately. Export the sequence file, chromatogram files, and the instrument audit-trail report to a controlled, read-only location. Record who performed each export, the time and date, and any actions taken at the instrument. Retain original files unaltered; work from verified copies for subsequent analysis. Contemporaneous operator notes that describe instrument messages, visible errors, or observed interruptions should be appended to the exported evidence to support chronological reconstruction.

Reconciling planned, executed, and aborted entries

Reconcile the planned injection list against the executed sequence by matching sample identifiers, injection timestamps, and run identifiers. Identify skipped, duplicated, shifted, or aborted injections and use audit-trail timestamps to build an event chronology. Preserve partial injection data where available and record the instrument status at interruption. Where aborted injections produced incomplete chromatograms, retain those files and flag them in the deviation record rather than deleting or overwriting them. This creates a clear trace linking planned entries to archived evidence used in the reviewer disposition.

Structured review and attributable documentation

Establish a documented review process that assigns reviewers, captures findings, and timestamps decisions. Reviews should reference preserved original files and any exported logs or screenshots. Document who reviewed each item, their role, and the rationale for conclusions. Maintain separate copies for review with clear links to the original files so that the original audit trail remains intact. Ensure entries meet data-integrity principles of attributable, contemporaneous, complete, legible, original, and retained, and that the documentation supports reproducible reviewer decisions.

Disposition decisions and controlled re-analysis

For each affected injection, record a disposition: accept as executed, re-inject under controlled conditions, further investigate, or void. Provide a rationale that cites preserved evidence such as chromatogram integrity, sequence logs, and instrument messages. Any decision to re-inject must include defined conditions (acceptable time window, sample handling checks, sequence position) and be recorded with the decision-maker identified. Link re-injection runs to the original planned entry and retain cross-references in the deviation record. Changes to electronic sequence files must be performed under change control and documented in the audit trail or a deviation report.

Data-integrity controls and audit readiness

Maintain accessible links between raw instrument files, exported sequence metadata, and the deviation record so reviewers and auditors can follow the chain of custody. Retain original chromatographic files and audit-trail exports to support retrospective review. Include screenshots or exported logs that capture sequence edits alongside narrative entries in the deviation file. Where applicable, reference relevant guidance to confirm expectations for original-data retention and audit-trail completeness.

For further procedural guidance on maintaining data integrity and retention practices, consult the FDA guidance on data integrity and CGMP recordkeeping at FDA Data Integrity and Compliance With Drug CGMP and the MHRA guidance on GxP data integrity at MHRA Guidance on GxP Data Integrity. Additional practices for audit-trail and original-data retention are described in the PIC/S guidance at PIC/S PI 041-1 Good Practices for Data Management and Integrity.

Close the record with an explicit disposition

After comparing the planned sequence with the instrument record, place each discrepancy into a clear review category such as skipped, repeated, incomplete, out of order, or not applicable. Link the relevant system evidence and note the reviewer’s reasoning for the recorded disposition. This makes the decision understandable without asking a later reviewer to infer the sequence from timestamps alone.

If the review identifies a broader process question, create or link the appropriate internal follow-up record rather than altering the original sequence history. Preserve the original plan, the executed record, and the triage note as related evidence. That approach keeps the laboratory record complete while allowing future procedural improvements to be tracked separately.

Not for human consumption. For laboratory research use only.