Separation of DNA Fragments by Capillary Electrophoresis Using a Mixture of Poly-[beta]-CD and Poly(ethylene oxide) as a New Sieving Matrix

In this study, we present the first example of the separation of DNA by capillary electrophoresis (CE) using a new sieving matrix, a mixture of the poly-β-cyclodextrin (poly-β-CD) and poly(ethylene oxide) (PEO). The poly-β-CD and PEO were used as a pseudostationary phase to improve the resolution of DNA fragments. CE separation was performed using a DB-17 coating capillary at an applied voltage of -10 kV (detector at anode side). Ammonium acetate buffer (25 mmol L-1, pH 6.0) was used as a background electrolyte and all sample solutions were prepared by the buffer. The best CE separation was obtained at a concentration of 5 mg mL-1 poly-β-CD and 1 mg mL-1 PEO. Under these conditions, 13 DNA fragments with sizes ranging from 200 bp to 4000 bp were completely resolved within 12 min, and the peak efficiencies ranged from 91000 to 234000 plates m-1. The results presented in this study show the advantage of PEO containing poly-β-CD for DNA separation, including rapidity, high resolving power, and ease of analysis.