how to get sharper peak shape?

[moonchips]

I am trying to develop a short assay for solubility screening.

I used YMC pro C18 column. 150x4.6x5 column.

what can i change to get sharper peak shape?

[skunked_once]

The easiest way is to slow down the chart speed on the integrator

Please post more information. We can't help without knowing the details of your method. We could suggest changes in flow rate, mobile phase, or the column.

[moonchips]

I need general suggestion of making peaks sharp:

high temperature, faster flow, initiall hold etc?

is isocratic usually sharper than gradient or broader than gradient?
will a sharper gradient result in sharper peaks or a shallowe gradient result in sharper peaks?

My main peak does not pass the peak purity test. Should I alway care about peak purity for the main API peak?

[mbulentcakar]

Hi,
Faster flows and gradients will work for sharper peaks. Also higher temperatures, and smaller particle diameter (larger plate count without peak broadening effect) will help.
Hope this helps.
Regards,
Bulent