How to Use This Troubleshooting Guide
HPLC problems almost always have a systematic cause. The key to fast troubleshooting is to isolate which part of the system is responsible before you start changing things. This guide is organised by symptom — find your problem, read the likely causes, then follow the step-by-step fixes in order from simplest to most complex.
Mobile Phase Reservoir
→
Degasser
→
Pump(s)
→
Autosampler / Injector
→
Guard Column
→
Analytical Column
→
Detector (UV/DAD)
→
Data System
Golden Rule of HPLC Troubleshooting
Change only ONE variable at a time. If you change the mobile phase, flush the column, AND replace the filter simultaneously, you will never know which change fixed the problem — and you cannot reproduce it reliably. Start upstream (mobile phase) and work downstream (detector). Document every change, every result.
Quick Diagnosis Reference — Find Your Problem Fast
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Symptom You See
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Most Likely Cause
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Jump to Section
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|---|---|---|
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Pressure higher than usual / rising gradually
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Clogged frit, guard column, or in-line filter
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Problem 1
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Pressure suddenly very high — system won't run
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Blocked column inlet or precipitated mobile phase
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Problem 1
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Pressure too low / unstable / fluctuating
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Air in pump, leaking fitting, or pump seal failure
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Problem 2
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Extra peaks I did not inject
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Carryover, contaminated mobile phase, column bleed
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Problem 3
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Peak is tailing (asymmetric, long right tail)
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Column void, secondary interactions, wrong pH
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Problem 4
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Peak is fronting (leading / wide left side)
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Overloaded column, sample solvent too strong
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Problem 4
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Peak is split / double peak
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Column void, void at frit, wrong sample solvent
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Problem 4
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Baseline noise / spikes / drift
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Air bubbles, dirty flow cell, lamp ageing
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Problem 5
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Peaks shifting earlier (shorter retention time)
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Mobile phase pH or organic % changed, column worn
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Problem 6
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Peaks shifting later (longer retention time)
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Flow rate too low, temperature drop, mobile phase error
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Problem 6
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System suitability — %RSD failing
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Injector problem, standard instability, leaking fitting
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Problem 7
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System suitability — tailing factor failing
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Column degradation, void, wrong pH, contaminated frit
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Problem 7
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Peaks too small / sensitivity dropping
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Dirty detector, wrong wavelength, standard degraded
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Problem 8
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No peaks at all
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No flow, wrong wavelength, injector not firing
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Problem 8
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8 Most Common HPLC Problems — Detailed Solutions
01
High Backpressure
System pressure is higher than the normal operating range for your method — or rising gradually over time
🔴 Critical — Stop run, investigate before continuing
Causes
Clogged in-line filter (most common) — particulates accumulate over time
Blocked guard column frit — sample matrix components block inlet
Analytical column frit clogged — particulates from sample or mobile phase
Precipitated mobile phase — buffer salts crash out at wrong pH or organic %
Kinked or blocked PEEK tubing
Column temperature too low — increases mobile phase viscosity
Wrong mobile phase flow rate — method set too high
Step-by-Step Fix
1. Disconnect column first. If pressure drops to near zero → column is the source. If pressure stays high → problem is upstream of column.
2. If upstream: Check and replace the in-line filter (between pump and injector). This fixes ~50% of high pressure cases.
3. If column source: Remove and replace the guard column cartridge first. Run pressure check. If still high, reverse-flush the analytical column with pure organic solvent (e.g. 100% MeOH at low flow, 0.1 mL/min) for 30 minutes.
4. Check mobile phase. Prepare fresh mobile phase ensuring correct pH and organic ratio. Precipitated buffers can clog everything downstream. Flush system with water then organic solvent.
5. If reverse-flush fails: The analytical column frit may be permanently blocked. Replace column. Document column injection history against maximum injection count in your SOP.
Prevention
Filter all samples through 0.22 µm or 0.45 µm membrane before injection
Always use a guard column — replace cartridge every 100–200 injections or per SOP
Replace in-line filter every 3–6 months or when pressure rises by >10%
Filter all mobile phase through 0.45 µm filter before use; use HPLC-grade solvents
Flush column with 100% organic solvent before shutdown — never leave aqueous mobile phase overnight
Record and trend system pressure at the start of each run — early detection of rising pressure
02
Low or Unstable / Pulsing Pressure
Pressure is lower than expected, fluctuating regularly, or the pump check valve chatters
🟡 Major — Results unreliable; investigate before reporting
Causes
Air in pump head — most common cause of pressure pulsation and low flow accuracy
Worn pump seal or piston — allows mobile phase to bypass the piston
Failed check valve — inlet or outlet check valve not seating correctly
Leaking fitting or connection — visible drips or wet fittings
Empty mobile phase reservoir — pump drawing air
Blocked solvent inlet filter (frit inside reservoir)
Step-by-Step Fix
1. Purge the pump. Use the pump purge/prime function at high flow (3–5 mL/min) for 5–10 minutes with the column disconnected. This expels any trapped air from the pump head.
2. Check all fittings for leaks. Run at normal pressure and inspect every connection — wet fittings, salt crystals, or discolouration indicate a leak. Tighten or replace ferrules/fittings.
3. Check check valves. If pressure pulsates rhythmically with pump strokes, the check valve is likely failing. Remove and sonicate in isopropanol for 30 minutes. Replace if still failing.
4. Check pump seals. If mobile phase appears in the drain line from the pump head, the piston seal is worn. Replace pump seals per manufacturer schedule or when pulsation persists after purging.
5. Check reservoir inlet filter. Remove the sinker/filter frit from the mobile phase reservoir and sonicate in methanol. Replace if permanently clogged.
Prevention
Degas mobile phase by helium sparging or vacuum filtration before use — remove dissolved air that leads to bubble formation
Replace pump seals preventively every 6–12 months (or per manufacturer recommendation) — before they fail
Never let the mobile phase reservoir run dry — keep minimum 20% volume at all times
Monitor pressure trend daily; a 10% drop may indicate developing leak or check valve wear
03
👻
Ghost Peaks (Unexpected / Spurious Peaks)
Extra peaks appear in the chromatogram that are not from the sample being injected
🔴 Critical — Can cause false OOS; investigate before any result is reported
Causes
Injector/needle carryover — residue from previous injection not fully washed out
Contaminated mobile phase — impurities in HPLC-grade solvent or buffer
Column bleed — stationary phase degrading and eluting
Contaminated sample vials or septa — plasticisers leaching from septa
Previous sample residue in loop — incomplete loop wash volume
Contaminated standard or reagent
Ghost peaks from gradient — mobile phase impurities — especially at low UV wavelengths
Step-by-Step Fix
1. Inject blank (mobile phase only). If ghost peak appears in blank → it is from mobile phase or column, not the sample or carryover. If blank is clean → it is carryover from sample.
2. For carryover: Increase needle wash volume and number of wash cycles in the autosampler method. Change the needle wash solvent to a stronger solvent (e.g. from water:ACN 50:50 to 90:10 ACN). Run blank injections between samples.
3. For mobile phase contamination: Prepare fresh mobile phase from new reagent lots. Filter through 0.22 µm. Run gradient blank to check mobile phase cleanliness before sample analysis.
4. For column bleed: Flush column with 100% organic solvent at low flow for 1 hour. If ghost peak persists and decreases with each blank injection, the column is degassing. Allow further column equilibration or replace column.
5. Check septa and vials. Use certified low-bleed PTFE/silicone septa. Replace vials with new certified HPLC vials — plasticiser ghost peaks from cheap vials at low UV wavelengths are common.
Prevention
Always run a gradient blank before first sample injection to check system cleanliness
Use certified HPLC-grade solvents and reagents — not ACS grade — for all mobile phases
Use certified low-bleed autosampler septa; replace after maximum use per manufacturer
Optimise needle wash: volume should be ≥3× the sample loop volume; wash solvent appropriate for your analyte
Include a system blank in every analytical sequence — early detection of new ghost peaks
04
Poor Peak Shape — Tailing, Fronting, Splitting, or Broadening
Peaks are asymmetric, split, unusually broad, or have shoulders — affecting system suitability tailing factor (T) and plate count (N)
🔴 Critical — Causes system suitability failure; results invalid
Tailing Causes
Tailing (long tail on right side, T > 2.0)
Column void — most common cause; void at head of column
Silanophilic interactions — basic analytes interacting with residual silanol groups
Mobile phase pH incorrect — ionisation of analyte or silanol groups
Contaminated column inlet frit — blocked or partially blocked
Dead volume in connections — extra-column band broadening
Sample overload — too high a sample concentration
Peak Broadening (high N but low k’)
Sample dissolved in too strong a solvent relative to mobile phase
Flow rate too high — analyte elutes before equilibrating
Fronting / Splitting
Fronting (leading edge, wide left side)
Column overload — injected mass exceeds column capacity. Dilute the sample.
Sample solvent too strong — dissolving sample in pure organic when mobile phase is mostly aqueous
Split Peaks / Double Peaks
Column void at inlet — most common; packing has settled leaving empty space
Partially blocked frit — sample takes multiple paths through column
Sample precipitation — compound partially precipitating in the sample solvent
Two compounds co-eluting — need to improve resolution; adjust mobile phase
Fixes & Prevention
Step-by-Step Fixes
1. Tailing fix: Try adjusting mobile phase pH ±0.5 units. For basic compounds, add 0.1% triethylamine (TEA) or switch to end-capped C18 column.
2. Column void: Cannot be fixed permanently. Try filling void by injecting column packing suspension. Replace column — void formation is a sign of end-of-life.
3. Fronting fix: Dilute sample 5–10× and re-inject. Dissolve sample in mobile phase composition rather than pure organic.
4. Dead volume fix: Replace all tubing with zero-dead-volume connectors. Use the shortest, narrowest bore tubing possible between injector and column.
Track tailing factor trend — increasing tailing over injections indicates developing void or contaminated frit
Prepare samples in mobile phase or weaker solvent when possible
Replace column before tailing factor exceeds 2.0 on system suitability check
05
〰
Baseline Problems — Noise, Drift, and Spikes
The baseline is not flat and stable — instead showing random noise, a gradual slope (drift), or sudden sharp spikes
🟡 Major — Affects detection limits, peak integration accuracy, and sensitivity
Causes by Type
Random High-Frequency Noise
Air bubbles passing through detector flow cell
Dirty or contaminated UV flow cell
Lamp nearing end of life (UV deuterium lamp)
Electronic interference from nearby equipment
Baseline Drift (gradual slope)
Column not fully equilibrated — especially after gradient
Column temperature fluctuating during run
Lamp warming up — needs 20–30 min after switch-on
Gradient elution — normal baseline change expected
Baseline Spikes
Particulates passing through flow cell
Static electricity in data cable
Step-by-Step Fix
1. Check lamp age. Access detector menu and check lamp burn hours. Replace deuterium lamp if approaching maximum rated hours (typically 1000–2000 hours). Lamp age is the #1 cause of rising baseline noise in UV detectors.
2. Degas mobile phase. If you see baseline spikes that look like bubbles, pass mobile phase through a vacuum degassing unit or helium-sparge for 10 minutes before use.
3. Clean the flow cell. Flush cell with 100% methanol, then 10% HNO₃ (caution), then water, then methanol again. For UV cells, use the manufacturer's recommended cleaning procedure.
4. Allow full lamp warm-up. Switch on the detector at least 20–30 minutes before starting any analysis run. Never start a run with a cold lamp.
5. For drift during gradient: Perform gradient baseline correction using a blank gradient run as reference, or set detector reference wavelength appropriately.
6. Check column oven temperature stability. Even ±0.5°C variation during a run causes baseline drift. Ensure oven is fully at set temperature before injecting.
Prevention
Log lamp hours at each service — replace lamp at 80% of rated life, not after failure
Always degas mobile phase; use inline degasser if available
Turn on detector 30 minutes before first injection — every day
Run a blank injection at the start of each sequence to confirm baseline stability before samples
Keep detector and instrument away from direct air conditioning vents and vibration sources
06
⏱
Retention Time Shifts — Peaks Moving Earlier or Later
Peak retention times are consistently shorter or longer than expected, or drifting within a single run sequence
🔴 Critical — Can cause misidentification of peaks; always investigate
Causes
Peaks Eluting EARLIER than expected
Mobile phase organic % too high — stronger mobile phase elutes everything faster
Mobile phase pH lower than method — affects ionisation of analyte and retention
Column temperature higher than set — increased diffusion reduces retention
Column degradation — loss of stationary phase reduces retention capacity
Peaks Eluting LATER than expected
Mobile phase organic % too low — weaker mobile phase increases retention
Flow rate too low — pump error or flow calibration needed
Column temperature lower than set — oven not reaching set point
Column not equilibrated — especially after changing mobile phase
Step-by-Step Fix
1. Verify mobile phase composition. Prepare fresh mobile phase and measure pH with calibrated pH meter. Verify organic:aqueous ratio by volume measurement. Even 1% error in ACN % causes significant RT shift.
2. Check flow rate accuracy. Collect mobile phase from column outlet for exactly 1 minute at your set flow rate. Weigh or measure volume — should be within ±2% of set value. If not, recalibrate pump.
3. Verify column temperature. Allow 20 minutes after setting oven temperature before injecting. Check oven temperature with calibrated external thermometer if drift is suspected.
4. Re-equilibrate column. After any mobile phase or temperature change, equilibrate for minimum 10–15 column volumes before injecting samples. For buffered systems, equilibrate until pH of waste matches mobile phase pH.
5. If drift worsens over the run sequence: Check for mobile phase reservoir running low (changing gradient composition), temperature slowly changing, or a developing leak changing effective flow rate.
Prevention
Measure and record mobile phase pH before every analytical run — not just at preparation
Use volumetric glassware for mobile phase preparation — not graduated cylinders for critical ratios
Allow full column equilibration at the start of every sequence (typically 20 column volumes minimum)
Calibrate pump flow rate quarterly and after any pump maintenance
Monitor retention time of reference standard injection across sequences — trend any drift >0.5 min
Use buffer concentrations ≥10 mM for robust pH control of mobile phase
07
System Suitability Test (SST) Failure
One or more SST parameters — tailing factor, plate count, %RSD, or resolution — fall outside acceptance criteria
🔴 Critical — Run MUST NOT proceed until SST passes. This is a GMP requirement.
SST Parameter — What Failure Tells You
%RSD Failing (>2.0%)
Most likely cause
Injector/leaking
Check first
Needle seal, loop
Also check
Standard stability
Acceptance
≤ 2.0% (5 inj.)
Tailing Factor >2.0
Most likely cause
Column void/worn
Check first
Column age/inj. count
Also check
Mobile phase pH
Acceptance
≤ 2.0 (USP)
Resolution <2.0
Most likely cause
Column degraded
Check first
Mobile phase fresh?
Also check
pH, temp, flow rate
Acceptance
Rs ≥ 2.0
Plate Count (N) Low
Most likely cause
Column degraded
Check first
Dead volume in tubing
Also check
Column temperature
Typical min.
≥ 2000 (method-specific)
Sensitivity / Response Low
Most likely cause
Standard degraded
Check first
Standard prep, lamp
Also check
Wrong wavelength
Acceptance
Per method SOP
Retention Time Wrong
Most likely cause
Mobile phase error
Check first
pH, organic %, flow
Also check
Column equilibration
Typical tolerance
±0.5 min from expected
SST Failure — What to Do (GMP Decision Tree)
SST Failure Detected — STOP. Do NOT proceed with sample analysis.
↓
Step 1: Investigate immediately. Identify which parameter failed and by how much.
↓
Is there an obvious, identifiable cause? (e.g. wrong mobile phase prepared, standard expired)
↓
✓ YES — cause identified
↓
Correct the issue. Re-run SST with full documentation. Proceed only if SST passes.
× NO — no obvious cause
↓
Initiate formal investigation. Do not proceed. Notify QC Supervisor and QA.
↓
Document everything: what failed, what was done, who authorised re-run. SST failure is a GMP event.
08
🔎
Low Sensitivity, Peaks Too Small, or No Peaks at All
Peaks are smaller than expected, below the LOQ, or completely absent from the chromatogram
🔴 Critical — Indicates major system failure; full investigation required
Causes
No Peaks / Flat Chromatogram
No flow — pump not running, tubing blocked, valve not switched
Wrong detection wavelength — set to wrong nm in detector method
Injector not firing — injection valve stuck or sample not loaded into loop
Sample not prepared / wrong volume
Peaks Too Small / Decreasing Over Time
Detector lamp at end of life — low intensity output
Reference standard degraded — actual concentration lower than expected
Dirty UV flow cell — deposits reducing light transmission
Wrong sample diluent causing analyte precipitation
Partial injector blockage — not all sample reaching column
Step-by-Step Fix
1. Verify flow. Disconnect column outlet and confirm mobile phase is flowing. If no flow — check pump is running, check all valves are in correct position, purge pump.
2. Check detection wavelength. Compare wavelength set in current instrument method vs. validated method SOP. Even 1 nm error at a sharp UV absorption peak causes large signal loss.
3. Test injector manually. Inject UV-absorbing tracer (e.g. caffeine solution) and confirm a peak appears. No peak from tracer = injector problem. Peak from tracer but not from sample = sample preparation issue.
4. Check reference standard potency and expiry. Recalculate response factor with freshly prepared standard. If standard response matches, sample preparation is the problem.
5. Clean or replace UV flow cell. Access flow cell and visually inspect for deposits. Flush with 10% nitric acid → water → methanol. If cell is etched or cracked, replace.
6. Check lamp energy output. Access detector diagnostics and check lamp energy/intensity reading. If <60% of rated output, replace lamp even if below maximum hour limit.
Prevention
Always verify detector wavelength matches method SOP before starting any run
Check reference standard preparation and potency at start of each analytical sequence
Log lamp energy/intensity values monthly and trend — plan replacement before failure
Clean UV flow cell quarterly or when baseline noise increases — prevention is far easier than emergency cleaning
Flush system and injector with appropriate wash solvent between sequences
Mobile Phase Preparation — The Most Overlooked Source of Problems
A large proportion of HPLC problems trace back to incorrectly prepared mobile phase. Here are the critical rules for error-free mobile phase preparation:
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Mistake
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Effect on Chromatography
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Correct Practice
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|---|---|---|
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pH measured before adding organic
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pH changes significantly when organic solvent is added — actual mobile phase pH different from target
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Measure and adjust pH of the aqueous portion only. Add organic solvent last. Note: buffer capacity is lower after organic addition.
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Buffer concentration too low (<10 mM)
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Poor pH control — small CO₂ absorption from air changes pH and causes retention time drift
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Use ≥10 mM buffer concentration for effective pH buffering. 20–50 mM is most robust.
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Wrong grade solvents used
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UV-absorbing impurities cause baseline noise and ghost peaks at low wavelengths
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Always use HPLC-grade or LC-MS grade solvents. Never use ACS grade for HPLC.
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Mobile phase not filtered
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Particulates clog column frit and in-line filter, causing rising backpressure
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Filter all mobile phase through 0.45 µm nylon or PVDF membrane before use.
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Not degassed properly
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Air bubbles cause baseline spikes, pump cavitation, and detector noise
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Vacuum filter (this simultaneously degasses) or helium-sparge for 10 minutes before use.
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Left overnight in open reservoir
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Evaporation of organic changes composition; bacterial growth in aqueous phase
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Prepare fresh mobile phase daily. Seal reservoirs. Discard any mobile phase >24 hours old.
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Phosphate buffer + organic >50% ACN
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Buffer salt precipitates at high organic %, clogs the column instantly
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Flush column with 10% aqueous before increasing organic above 50%. For high-organic methods, use formate or acetate buffers which are more soluble.
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HPLC Column Care & Lifetime Management
Your column is the most expensive and most critical consumable in your HPLC system. Proper care extends its life significantly and prevents the most common problems.
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Do This
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Why
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|---|---|
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Always flush with 100% organic before shutdown
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Aqueous mobile phase left overnight promotes microbial growth and salt crystallisation — both permanently damage the column packing
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Never exceed the column's maximum operating pressure
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Over-pressuring cracks the packing, creates voids, and permanently destroys column efficiency
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Store column in 80–100% organic solvent (MeOH or ACN)
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Prevents microbial growth during storage; keeps packing in good condition
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Track injection count and record in a column logbook
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Allows you to retire the column proactively before performance declines — prevents unexpected SST failures
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Run a column performance test before use on a new lot
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Establishes baseline N, T, and Rs values — gives you data to compare against as the column ages
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Use a guard column every time
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Sacrificial protection — sample matrix components block the guard column frit, not the analytical column. Replace guard every 100–200 injections.
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Equilibrate fully after storage or mobile phase change
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30–50 column volumes is needed after switching mobile phase. Insufficient equilibration causes retention time drift throughout the run.
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Reverse-flush column periodically
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Backflushing with 100% organic at low flow (0.1 mL/min) dislodges accumulated sample matrix from the inlet frit and can restore performance
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Preventive Maintenance Schedule — Keep Your HPLC Running
Most HPLC problems can be prevented entirely with a structured preventive maintenance programme. Here is a practical schedule for a busy pharmaceutical QC laboratory:
Daily
- Check mobile phase levels; top up / prepare fresh
- Purge pump at start-up (2 min, 3 mL/min)
- Run system blank before first sample
- Record system pressure at start of run
- Check for leaks at all fittings
- Verify detection wavelength matches method
- Flush with organic at end of day
- Record SST results in logbook
Weekly
- Replace in-line filter if pressure has risen
- Replace autosampler needle wash solvent
- Clean needle wash port
- Inspect all tubing for kinks or discolouration
- Check autosampler needle for burrs
- Review retention time trend data
- Flush waste lines
Monthly
- Replace in-line filter (preventive)
- Clean UV flow cell
- Check lamp energy output; log hours
- Verify pump flow rate accuracy
- Replace guard column cartridge
- Review column injection count log
- Check autosampler seal condition
- Sonicate check valves if pressure pulsation noted
Quarterly / Annual
- Replace pump seals (annual or per manufacturer)
- Replace deuterium lamp (at 80% rated hours)
- Replace autosampler needle (annual)
- Calibrate pump flow rate
- Calibrate column oven temperature
- Full IQ/OQ/PQ requalification (annual)
- Replace all system tubing (2-year cycle)
Frequently Asked Questions
Signs that an HPLC column is at end of life: (1) Tailing factor >2.0 that cannot be improved by mobile phase adjustment; (2) Theoretical plate count (N) significantly below its original value (typically >30% reduction); (3) Resolution between critical peak pairs consistently below 2.0; (4) Retention times drifting run-to-run despite correct mobile phase; (5) Irreversibly increasing backpressure despite guard column replacement. If reverse-flushing with 100% organic for 1 hour doesn’t restore performance, the column is typically at end of life. Always record the injection count — most C18 columns perform well for 500–2000 injections depending on sample matrix complexity.
In GMP pharmaceutical laboratories, it is generally not recommended to reuse HPLC mobile phase. The reasons: (1) Aqueous components promote microbial growth overnight; (2) Open reservoirs allow evaporation of organic solvent, changing the composition and pH; (3) Re-using increases risk of trace contamination affecting impurity methods. Most pharmaceutical laboratory SOPs specify mobile phase must be freshly prepared each analytical day and discarded after 24 hours. For non-aqueous organic-only mobile phases (e.g. hexane-based normal phase), reuse may be acceptable for 2–3 days if sealed, but verify against your SOP.
An in-line filter (typically 0.5 µm stainless steel frit) is placed between the pump and injector to remove particulates from the mobile phase before they reach the injector and column. It has no stationary phase — it only filters. An guard column is placed between the injector and the analytical column. It contains the same stationary phase as the analytical column and acts as a sacrificial first stage — catching sample matrix components, strongly-retained compounds, and particulates before they reach the expensive analytical column. Both should be used together — the in-line filter protects from mobile phase contamination; the guard column protects from sample matrix contamination. Replace the guard column every 100–200 injections; the in-line filter monthly or when pressure rises.
Yes — in GMP pharmaceutical laboratories, an SST failure is a quality event that must be documented. The minimum actions are: (1) Stop the analytical run immediately; (2) Investigate the root cause; (3) Document what failed, why, and what was done to resolve it in the analytical logbook or LMS; (4) If the run was restarted after fixing the issue, document the authorisation. Whether a formal deviation or CAPA is required depends on whether the cause was a simple correctable issue (e.g. wrong mobile phase prepared — document and correct) or a systemic problem (e.g. pump seal failure — may require formal deviation and investigation). Your site SOP should define the threshold for formal deviation initiation vs. simple corrective entry in the analytical record.
Per USP <621> and ICH Q2(R1), system suitability typically requires a minimum of 5 replicate injections of the reference standard to calculate %RSD. Some methods specify 6. For tailing factor and theoretical plates, typically 5 injections are used and the average value reported (though USP allows calculation from a single injection for T and N). The resolution (Rs) is calculated from a single injection of a mixture containing the critical peak pair. Always follow your validated method SOP — if it specifies more than the USP minimum, you must follow the SOP regardless.
Regulatory Basis for HPLC System Suitability
|
Reference
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Relevance to HPLC in Pharma QC
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|---|---|
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USP <621> — Chromatography
|
Defines system suitability parameters, calculation methods, and minimum requirements for tailing factor, theoretical plates, resolution, and %RSD in pharmaceutical HPLC
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ICH Q2(R1) — Analytical Method Validation
|
System suitability is linked to validation — SST criteria are derived from the method validation data and must be met before every run
|
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FDA 21 CFR 211.68
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Requires that analytical instruments are of appropriate design, adequate capacity, and suitably maintained — the legal basis for instrument qualification and SST
|
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USP <1058> — Analytical Instrument Qualification (AIQ)
|
Defines IQ/OQ/PQ requirements for HPLC systems; qualifications must be current for results to be GMP-acceptable
|
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FDA Data Integrity Guidance (2018)
|
All HPLC data — including raw chromatograms and integration parameters — must be stored with audit trail; no manual deletion of runs or peaks
|
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EU GMP Annex 11
|
Computerised systems guidance — HPLC software (CDS) must have access control, audit trail, and backup in place
|
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ALCOA+ Principles
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All HPLC data must be Attributable, Legible, Contemporaneous, Original, and Accurate — applies to raw data files, integration, and result reporting
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