Typing of esterase D by isoelectric focusing

Abstract

AbstractA method is described for obtaining reproducible resolution of Esterase D (EsD) phenotypes from human bloodstains by ultrathin‐layer polyacrylamide gel isoelectric focusing. By employing a pH 4.5–5.5 gradient and an electrode wick distance of 9.5 cm, all the common EsD variants were separated in 85 min. Electrofocusing of EsD took 53 and 60 min on the Cold Focus Apparatus and Ultrophor, respectively, when the distance separating the electrodes was 8.0 cm. Bloodstains up to 4 weeks old could be readily typed for EsD using this method.