In the Sanger sequencing workflow, it is necessary to remove excess primers and unincorporated nucleotides from the PCR reaction prior to sequencing, as any leftover primers can interfere with the strand-specific cycle sequencing reactions that will follow.
A proven highly effective method is the enzymatic clean-up of amplified PCR product, hydrolyzing excess primers and nucleotides in a single step, utilizing two recombinant hydrolytic and heat-labile enzymes, Exonuclease-I and Shrimp Alkaline Phosphatase.
ExS-Pure™ is a ready-for-use reagent containing a well-balanced mixture of these effective enzymes and is the widely adopted drop-in alternative to ExoSAP-IT™. Prior to cycle sequencing, ExS-Pure™ is added directly to the PCR product, and clean-up is performed in a standard thermal cycler within 5 minutes.
ExoSAP-IT is a trademark of Thermo Fisher Scientific.