Stat3 EMSA (Electrophoretic-Mobility Shift Assay) kit is used for monitoring Stat3 (Signal transducer and activator of transcription 3) DNA binding activities and activation. Upon activation, Stat3 can recognize and interact with the unique DNA binding sequence and form protein/DNA complex, which can be separated from free DNA due to the differences in their electrophoretic mobility in native (non-denaturing) polyacrylamide gels.