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Sample and Standard peak area found in the ratio of 1:6 ratio during HPLC analysis

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 Sample peak at RT about 4.5 min. with height of about 90 Standard peak at RT about 4.5 min. with height of about 630 Investigation : When such phenomenon was observed then analyst was interviewed and detailed discussion done about level of dilutions done during sample and standard solution preparation. As per the Standard testing procedure, std was to be taken as 50 mg and sample was to taken as Equivalent to 50 mg active substance. Now, the analyst weighed correctly 50.2 mg of standard but during sample weighing he took the similar weight as 50.5 mg. Here the point is weight of tablet under analysis is 300 mg. Hence, the actual weight is to be taken as 300 mg as each tablet contains 50 mg of active content. This resulted in Sample peak height to Standard peak height in the ratio of 1:6. Conclusion : This is the common mistake in pharma lab which is sometime done by analyst. They should clearly distinguish between the word Equivalent and Equal . Though this seems silly mistake but m
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Drift in the analyte Retention time in HPLC analysis

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Drift in Retention time of Analyte peak during HPLC analysis: Causes:  There are several reasons of observing drift in Analyte peak in HPLC analysis  like: a. There is slight leakage in pump due to which RT shift is observed in the chromatogram b. Insufficient  saturation of HPLC column as every column behaves in different manner and take different time to get saturated c. Insufficient sonication of Mobile phase which involves solvents like Acetonitrile which requires minimum 15 to 20 mins. of sonication to remove entrapped air bubbles d. Incorrect selection of column for analysis. Remedies :  a. Any type of leakage which might at pump or detector, must be immediately fixed. It might be possible fer rules are not tightened properly which must properly tightened  b. Column saturation  should be done to get stable baseline. Once it is free from any types of noise, standard injection to be done. c. Mobile sonication should be done for minimum 20 minutes to avoid any bubbles entrapment in
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Peak of Lanreotide not detected on Thermo HPLC

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Description:   Peak of Lanreotide not detected on HPLC of Thermo make. Investigation:  Investigation was done to find the root cause for above issue. Mobile phase changed multiple times. All HPLC tubings were checked for any kind of leakage but no issue was observed. Root Cause : To identify the root cause service engineer of Thermo was contacted. He took multiple trails but not succeeded.  After that he identifies that during method preparation calibration curve value taken was 5. As per his opinion it should be 6 for Thermo HPLC otherwise principle will not be detected. The same method was previously run on waters make HPLC where calibration curve was 6 and the same wss latter included in method, but when run on Thermo make HPLC,  peak was not detected. Conclusion: It is to be noted that calibration curve value play significant role during run on different HPLC systems. It is to be modified during development studies so that final method should include the correct value.  If anybody
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Interference of Toluene peak during GC Analysis

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  Description of Incident:  During analysis of one of the Active content during GC analysis, peak interference of Toluene observed.  Investigation:  During Investigation it was found that in every injection on GC, peak of Toluene was eluting. It was checked and found that Toluene was not used in that particular analysis then also Toluene peak was eluting. To rule out the possibility of chemical contamination, new bottle of DMSO was opened. After using new bottle reagent also, Toluene peak was eluting  and no significant drop in area was observed. Root cause:  During further Investigation  it was observed that during previous analysis Toluene was used as an standard.  Currently the oven temperature  was kept as 120°C (as boiling point of Toluene is 110°C) to remove the traces of Toluene but then also Toluene peak was observed.  Remedy :  As a corrective action, oven temperature was increased to about 200°C and column condition done for about half an hour. After that blank was infected a
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Peak area observed less than the trend during HPLC analysis

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Trouble description : During HPLC analysis, sometimes it happens that there is significantly less area observed as compared to previous trend od peak area. Investigation :  During investigation everything was checked i.e.: Checke Solution dilutions prepared for sample and standard and found Ok. Checked Column leakage and found no leakage. On changing the HPLC system, same solutions were used and arwawere checked  Mobile phase filteration checked and it was found that analyst did not filterd the mobile phase As unfiltered mobile phase was used,so solvent inlet filter was checked On inevstigating it was found that they were completely choked. Action taken : Solvent inlet filter was changed and analysis performed. Area observed in trend. CAPA: Solvent filter should be sonicated for 30 mins if any variation is observed during the analyis.
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XZ drive failure in Ion Chromatography of Thermo Scientific make

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  In an reputed pharma company, in IC system, XZ drive failure was observed.  Root cause analysis:  The system was shutdown for about 8 months. So initially it was not known that why such thing happened. Just as instrument was started and XZ drive failure took place. During investigation it was found that earthing observed as 2.4 ohms which is more than the requirement of NMT 1 ohms. Actually at the time of installation it was 1.4 ohms two years back. Due to increase in load, earthing increased upto 2.4 ohms which resulted in failure of XZ drive of IC instrument.  Cost of new drive is about $ 9000. Precaution: It is highly advisable to keep close check on earthing during operation of sophisticated instruments like IC system otherwise it can result in high costly affair.
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Case study of Incident observed during HPLC analysis

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Case study of Incident observed during HPLC analysis on Waters auto sampler:   Recently during HPLC analysis on Waters make HPLC, a very unique incident happened. During Related substance analysis, after 3 standard injection, in fourth injection missing vial was observed though injection was taken from same single vial. Root cause analysis: Further on investigation it was identified that at the time of vial labelling, analyst used small sticker. So at the time of vial picking by robot in autosampler, small piece of sticker on inside wall of vial carousol. Due to this robot tried to pick the vial but due to resistance from vial, robot was not able to pick the vial. This resulted in above incident and missing vial message was obseeved. On prima facie it was difficult to find the root cause but due to so small sticker, such sticker can cause the incident. Remedy :  Never apply sticker labels on vials and always use marker pen to assign the identification on vial. Hope you may get some hel
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