Simultaneous separation diclofenac and pentachlorophenol

[mikrogabrysienka]

I try do develop method to separate pentachlorophenol (PCP) diclofenac (DCL), and octylphenol with simultaneous method.
I use C18 Column, UV-VIS detector and mobile phase = ACN:H2O (95:5)/ (85:5). Octylphenol is well separated but the retention time of PCP and DCL are very similar and there is option to separate them. I' ve tried flow 1 ml/min and 0.5 ml/min and different wavelength (254, 220).
What should I do more to separate PCP and DCL well... ?
I really need more information.
Thanks

[dblux_]

µGabrysienka, have you considered starting with less concentrated ACN ?

[mikrogabrysienka]

µGabrysienka, have you considered starting with less concentrated ACN ?

Yes, I 've tried with ACN/H20 =60/40, and I lost DCL

[dblux_]

µGabrysienka, have you considered starting with less concentrated ACN ?

Yes, I 've tried with ACN/H20 =60/40, and I lost DCL

What is the order of elution of your compounds ?
If DCL is the last one, then gradient elution may help. Am I right that your separation is isocratic?

[mikrogabrysienka]

µGabrysienka, have you considered starting with less concentrated ACN ?

Yes, I 've tried with ACN/H20 =60/40, and I lost DCL

What is the order of elution of your compounds ?
If DCL is the last one, then gradient elution may help. Am I right that your separation is isocratic?[/quot
Yes my elution is isocratic, DCL is second, the last one is OP. Thank you, I am trring tomorrow this option.