By Lime on Tuesday, September 23, 2003 - 05:53 am:
Hi !!
I am wondering how many days/weeks/months do you use your mobile phase ? I know it depends on what kind of buffer or organic we use. But average will be enough for me.
For example
1- 50% organic 50% buffer ........ ?
2- 100 % buffer ...........?
3- 80% organic 20% buffer......?
4- 50% organic 50% water.....?
5- 80% organic 20% water......?
Thanks for all answers...
By Anonymous on Tuesday, September 23, 2003 - 07:00 am:
1,3,4,5 2 weeks in a clear bottle (1 liter)
3 in an amber one
2. 3 days clear, 1 week amber
By Anonymous on Tuesday, September 23, 2003 - 10:31 pm:
YOU HAVE TO PERFORM STABILITY OF MOBILE PHASE BY KEEPING IT ON BENCHTOP AND ALSO KEEPING IN REFRIGERATOR ,
YOU HVE TO KEEP THIS MOBILE PHASE ON SYSTEM AND PREPARE A FRESH SAMPLE WITH FRESH MOBILE PHASE DILUENT AND PERFORM THE ANALYSIS AND COMPARE WITH THE SAMPLE ANLAYSE WITH FRESH MOBILE PHASE AND SET THE SPCIFICATION FOR THE ACCEPTANCE LIMIT AND GIVE THE STABILITY TO THE MOBILE PHASE AS IN YOUR CONDITION MOBILE PHASE PH MAY CHANGE OR ORGANIC COMPOSITION MAY CHANGE WHICH LEADS TO CHANGE IN RESPONSE OR BROADNANING OF THE PEAK OR MANY CAUSES OF CHROMATOGRAPHY LIKE TAILING SO THIS IS VERY CRITICAL PARAMETERS PEOPLE WHO FOLLOWS FDA DOES IT SOMETIMES TO SATISFY THEM
By Anonymous on Wednesday, September 24, 2003 - 07:22 am:
What??? Punctuation helps! Also, writing in caps is considered SHOUTING!
By R.C. on Monday, September 29, 2003 - 12:41 pm:
A lot of things can happen to HPLC eleuent. It can oxidize in th air, lose volitile components, or microbes can grow. Exactly when this will become a problem depends on your analytical needs and the environment of your lab. You have to test your eluents over time as was suggested, or prepare fresh every day. As an example, we have 6 month dating for high solvent eluent, and one month dating for high and low pH aqueous salt buffers. Neutral pH organic buffers are a problem -- and their stability depends on climate, season, and facility.