No other analytical technique, including pre-column derivatization followed by reversed-phase chromatography, has been shown to match post-column ion-exchange methods in accuracy and reproducibility. This is because the retention mechanism in ion exchange provides for chromatography that is almost completely matrix-insensitive. Simple sample preparation for native samples is an added benefit of the ion-exchange method.
With the alternative pre-column derivatization method, the prepared sample is subject to a chemical reaction that takes place in a very complex medium: the residual matrix. Matrix complexity produces both competition and inhibition in chemical synthesis, resulting in decreased reproducibility in peak areas and retention times. Very often, the pre-column method must be optimized for each different sample matrix. In contrast, ion-exchange chromatography followed by post-column derivatization is intrinsically more rugged and repeatable, since the matrix components do not retain on the cation-exchange column and have no influence on separation or derivatization of amino acids. The same method can be used for variety of samples, from plant extracts to serums or spinal fluids.
Pickering Laboratories, Inc. provides a complete solution to Amino Acid Analysis. We supply columns, eluants, reagents and post-column derivatization instruments that work seamlessly with virtually any modern HPLC, so we can guarantee the accuracy and reproducibility of the analysis. Our chemists will help you choose the method and instrumentation best suited to your requirements, work with you on any custom method optimization and offer continuous support in day-to-day operation.
Download a copy of the brand-new Amino Acids Analysis brochure here. Do not hesitate to contact Pickering Labs Support (support@pickeringlabs.com) with any questions.
David Mazawa
Technical Support Chemist
Pickering Laboratories, Inc.
1280 Space Park Way
Mountain View, CA 94043, USA
david@pickeringlabs.com
Phone: (650) 694-6700 x710