There are tons of papers describing the purification and(or) measurement of Absic acid with HPLC. Pubmed it!!

Brother follow this method and enjoy ur research work...........

Determination of phytohormone:

Extraction, purification and quantitative determination of endogenous hormones, namely gibberellic acid (GA3), indole acetic acid (IAA) and abscisic acid (ABA) were carried out according to the methods of Ünyayar et al., (1996) and Baydar & Ülger (1997). Analyses of GA3, IAA and ABA were performed on a Model Varian 9050 HPLC equipped with UV detector and Model Varian 9010 pumps enabling the use of a concentration gradient of the mobile phase. Separations and determinations were performed on a nukleosil C18 column (4.6 mm x 150 mm). The Mobile phase yielded results of 30% methanol (adjusted to pH 3.0 with 0.1 M H3PO4) for GA3, 55% methanol (in 0.1 M acetic acid) for ABA and 35% methanol (in %1 acetic acid) for IAA. The total run time for separations was approximately 15 min at a flow rate of 1 ml/min. GA3, IAA and ABA were detected by their absorption at 280, 208 and 265 nm, respectively and the peak area of the samples were compared to the corresponding peak areas of standard solutions containing known concentrations of GA3, IAA and ABA.

Dear Asad,

Thanks for your helpful answer.

Kind regards,

Hossein

Dear Sir,

               You can find answer especially after reading the following paper.

Dear Sir, I hope these papers can help you

Regards

Dear Heshmat and maite,

Thanks for your help.

Kind regards,