Why is there is no peak when dissolving hederagenin in methanol by HPLC?

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Luciano Rivera

Considering that the hederagenin have a Log P closer to 5, try to change the solvent, like acetone or add a fraction of this, may be this molecule is slightly soluble in methanol.

Bizhang Dong

Please provide a picture! You can change mobile phase.

Liuping Miao

What is your current mobile phase? You can try to add some acetic acid or triethylamine to the mobile phase.

Inas Elatik

thank u for all ,my mobile acetonitrile water 32:68 with ,05%formic acid on C18 column ,wave lenght 210nm, temp 30. conc 1mg/ml.I get early unconstant peaks early.and small peak at RT 4min flow1ml/min. should Ihave to change column and decrease polarity of system