How to establish pKa for a new API molecule ?

2 Answers   Neuland, Sun Pharma,

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My question about gas chromatography sulfur chemiluminsecence detector. I test unknown sample gas by GC-SCD (calibrated ) and the result of *H2S is 279 PPM , *but when I test the same sample with the GC-TCD (calibrated ) the value of *H2S is 2500 PPM . I'd like to inform you that both GCs are calibrated and have very good operation conditions with stable parameters . the question is if the sample gas with higher H2S over detection limits of SCD detector (1000 ppm). why the result it 279 ppm Best regards

0 Answers  

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What is the purpose of octyl silane columns?

0 Answers  

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1)why use benzophenon,uracil in hplc calibration. 2)why use sucrose in polarimeter calibration. 3)what is S/N ratio, noise and drift in hplc 4)how we can find lod and loq in method validation

1 Answers  

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what is the meaning of ventillation in HPLC?

3 Answers   Amneal Pharmaceuticals,

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In GC Why does retention time decrease when temperature increases? Also how does a change in temperature effect selectivity?

1 Answers   Gland Pharma,

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What is the formula for relative diffrence for standard solution in solution stability in validation?

0 Answers  

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What is the difference between specified impurity and Identified impurity

3 Answers   Glenmark,

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if the flow rate is increases then any changes in retention time in hplc

1 Answers  

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WHEN AN UN KNOWN SAMPLE IS GIVEN TO U,HOW WILL U START THE ANALYSIS(ie FIRST WHICH TEST TO BE DONE,NEXT,THEN NEXT),HOW WILL U DECIDE WHICH TYPE OF ANALYSIS TO BE DONE FOR IT?

2 Answers   Aurobindo,

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in hplc chromatogram started from left to right and in uv spectrum started from left to right

0 Answers  

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What are the primary standards?

6 Answers  

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