CE of poly(amidoamine) succinamic acid dendrimers using a poly(vinyl alcohol)-coated capillary

Authors

  • Ankur Desai,

    1. Michigan Nanotechnology for Medicine and Biological Sciences, University of Michigan, Ann Arbor, MI, USA
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  • Xiangyang Shi,

    1. Michigan Nanotechnology for Medicine and Biological Sciences, University of Michigan, Ann Arbor, MI, USA
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  • James R. Baker Jr. Professor

    Corresponding author
    1. Michigan Nanotechnology for Medicine and Biological Sciences, University of Michigan, Ann Arbor, MI, USA
    • Michigan Nanotechnology for Medicine and Biological Sciences, University of Michigan, Ann Arbor, MI 48109, USA Fax: +1-734-936-2990
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Abstract

Various generations (G1–G8) of negatively charged poly(amidoamine) (PAMAM) succinamic acid dendrimers (PAMAM-SAH) were analyzed by CE using a poly(vinyl alcohol)-coated capillary. Due to its excellent stability and osmotic flow-shielding effect, highly reproducible migration times were achieved for all generations of dendrimer (e.g., RSD for the migration times of G5 dendrimer was 0.6%). We also observed a reverse trend in migration times for the PAMAM-SAH dendrimers (i.e., higher generations migrated faster than lower generation dendrimers) compared to amine-terminated PAMAM dendrimers reported in the literature. This reversal in migration times was attributed to the difference in counterion binding around these negatively charged dendrimers. This reverse trend allowed a generational separation for lower generation (G1–G3) dendrimers. However, a sufficient resolution for the migration peaks of higher generations (G4–G5) in a mixture could not be achieved. This could be due to their nearly identical charge/mass ratio and dense molecular conformations. In addition, we show that dye-functionalized PAMAM-SAH dendrimers can also be analyzed with high reproducibility using this method.

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