Evaluation of capillaries with different inner coatings for DNA analysis using dilute polymer solutions by capillary electrophoresis

in this work three capillary columns, one with uncoated inner wall and two with covalently-bound internal coatings - poly(vinyl alcohol) (pva) and poly(dimethylacrylamide) (pdma) - both covalently covered - were used to separate dna fragments and compared to dna separation using replaceable polymer solutions. the separations were performed using hydroxyethylcellulose (hec) (90-105 kda) in concentrations ranging from 0.00 to 2.00% m/v. the results indicated that the separation efficiency was higher in the pva capillary than in the pdma in all evaluated concentrations of hec. in addition, higher resolution was also observed in pva-coated capillary since in pdma the shape of the peaks was not reproducible when subsequent runs were performed. contrary to what has previously been reported in the literature, no reasonable separation was possible in bare fused silica.