how to increase the response ......

[parveenqa]

dimensions of column i am usong: Betasil C18 column
Dim(mm): 250*4.6
particle size: 5 micron

[WK]

parveenqa,
You won't get much of an answer with little information.
How about HPLC parameters?
What analysis are you performing?
Sample preparation / standard concentrations etc.
What S/N are you getting?

WK

[JGK]

dimensions of column i am usong: Betasil C18 column
Dim(mm): 250*4.6
particle size: 5 micron

without changing the method moving to a 2.1 mm diameter column and halving the flow rate will double your existing peak height.

Alternatively, are you using the best detector for the job or can you adjust the detector the give an improved response.

There are a multitude of possibilities but, without more information about your analysis, we can not be of much help

[Bryan Evans]

Reducing particle size from 5um to 3um will increase sensitivity:

http://www.imtakt.com/TecInfo/TI058E.pdf

[danko]

changing the method moving to a 2.1 mm diameter column and halving the flow rate will double your existing peak height.

Actually, if moving from 4.6 to 2.1 column diameter, the flow rate should be multiplied by 0.208.
In theory, the expected peak height increase will be 4.8 times, but in my experience increase between 3 and 4 times is a reasonable expectation.

Best Regards

[JA]

Only because they were so close in the thread list when I looked, I suspect this topic is a direct continuation from;

http://www.sepsci.com/chromforum/viewto ... 9264#43389

[parveenqa]

thankyou for your informations