ABSTRACT
All pulsed-field gel electro-phoresis (PFGE) systems rely on the phenomenon of deoxyribonucleic acid (DNA) reorientation for fragment separation by subjecting the molecules to at least two alternating electric fields. This chapter focuses on the contour-clamped homogeneous electric field and field inversion gel electrophoresis (FIGE) systems, which are versatile and easy to operate. Several physical and chemical factors affect the passage of DNA fragments during PFGE, e.g. agarose concentration, DNA concentration, pulse times, pulse ratio in FIGE, strength of electric field, and temperature, ionic strength, and pH of the running buffer. The great advantage of PFGE over conventional agarose electrophoresis is undoubtedly the resolution that can be achieved between the fragments generated by restriction endonuclease digestion of DNA. A mathematical approach to the analysis of PFGE patterns was proposed for S. aureus by El-Adhami et al.
