Separation of DNA with hydroxypropylmethyl cellulose and poly(ethylene oxide) by capillary gel electrophoresis

Hydrophilic polymers, hydroxypropylmethyl cellulose (HPMC) and polyethylene oxide (PEO), were employed both for the dynamic coating of the capillary surface and for the sieving matrix. Although PEO showed somewhat better coating efficiency, it was found that both HPMC and PEO as the dynamic coating polymers were not able to maintain the capillary surface coating during the separation of deoxyribonucleic acid (DNA) fragments. However, the continuous supply of PEO chain from the bulk made it possible to maintain the surface coating. An interesting result was obtained with DNA intercalating dye, ethidium bromide (EB). Better resolution was obtained with the use of EB probably due to the change of radius of gyration (Rg) of DNA.