ALLInterview.com :: Home Page            
 Advertise your Business Here     
Browse  |   Placement Papers  |   Company  |   Code Snippets  |   Certifications  |   Visa Questions
Post Question  |   Post Answer  |   My Panel  |   Search  |   Articles  |   Topics  |   ERRORS new
   Refer this Site  Refer This Site to Your Friends  Site Map  Bookmark this Site  Set it as your HomePage  Contact Us     Login  |  Sign Up                      
Google
   
 
Categories >> Sciences >> Chemistry >> Analytical Chemistry
 
 


 

 
 Organic Chemistry interview questions  Organic Chemistry Interview Questions (228)
 Inorganic Chemistry interview questions  Inorganic Chemistry Interview Questions (96)
 Analytical Chemistry interview questions  Analytical Chemistry Interview Questions (868)
 Physical Chemistry interview questions  Physical Chemistry Interview Questions (57)
 General Chemistry interview questions  General Chemistry Interview Questions (284)
 Chemistry AllOther interview questions  Chemistry AllOther Interview Questions (71)
Question
How we can analysed unknown sample by hplc....
 Question Submitted By :: Analytical-Chemistry
I also faced this Question!!     Answer Posted By  
 
Answer
# 1
First take ir of that sample and judge the functional
goroups attached to that compound and also structure of
that compound.
then check solubility.
then UV scan with known concentration and find lymda max.
then selection of column.
first try with regular solvent like water, acn,
methanol.and then go to the buffers of different pH.near to
its pka value.
also different coloumn.
 
Is This Answer Correct ?    0 Yes 0 No
Ravindra
 
Answer
# 2
first check the structure of the compound.identify the
chromophore groups(for UV Detector),refractive index status
(for RI Detector),reactive status with other chromophore
group compounds(Derivitation method for UV.then check the
solubility status of the compound.prepare a known
concentration solution.

In HPLC select a C18 Column which can serve better for the
polar and not polar compounds.select a buffer pH Oof +/-1
unit of pka value of the compound prepare a buffer mix with
some 20% of organic solvent to chnge the elution early
(based on polarity)

inject the prepared known concentration sample solution in
to above system by observing the chromatogram procced
further by altering buffer
pH,COLUMN,FLOW,TEMPERATURE,ORGANIC RATIO Sample size etc.

but to quantify the unknown concentration we need a known
concentration of standard.
 
Is This Answer Correct ?    0 Yes 1 No
Balaji
 
 
 

 
 
 
Other Analytical Chemistry Interview Questions
 
  Question Asked @ Answers
 
give tha clarity about peak purity concept Aurobindo 3
what is specificity? Amneal-Pharmaceuticals 4
how can we calculate void volume?give its importance in brief Natco 1
What is post run in hplc? Cipla 1
what is the principal of malvern particle sizer & its used in pharma industry   2
1 WHY POLYESTERENE FILM USED FOR FTIR CALIBRATION ? 2 WHY k2CR2O7 IS USED FOR CONTROL OF ABS IN UV ? 3 WHY HOLMIUM OXIDE USED FOR CONTROL OF WAVELLENGHT IN UV   2
WHY KBR IS USED IN IR FOR PREPARATION OF PELLETE,WHY IT SHOWS ZERO DIPOLEMOMENT GVK 2
what is the value of pH Reddy-Labs 10
how to calibrate AAS ? give me the procedure?   2
difference between record & document ?   4
what is difference between IR & FTIR ? how we calibarte both ? I want to know the procedure. Cadila 6
Why 1.2% KCl is used for limit of stray light? and why limit of stray light is required in UV calibration? Lupin 3
 
For more Analytical Chemistry Interview Questions Click Here 
 
 
 
 
 


   
Copyright Policy  |  Terms of Service  |  Articles  |  Site Map  |  RSS Site Map  |  Contact Us
   
Copyright 2013  ALLInterview.com.  All Rights Reserved.

ALLInterview.com   ::  KalAajKal.com