An electrophoretic system is provided which allows for carrying out electrophoresis while monitoring and regulating the temperature and the electrical field gradient in the gel. In addition, photometric monitoring, including use of an optical stage, is provided so as to monitor the progress of the electrophoretic separation and vary conditions to change the progress as desired. A computer is employed which receives the signals from the electrophoretic and photometric apparatuses and regulates temperature and voltage to either maintain conditions, or change the conditions to vary the progress of the electrophoresis and to store the separation results. A sample applicator and a sample retriever are also provided, to provide even and consistent application of sample to the gel and to allow recovery of portions of the sample without destroying or removing pieces from the gel. Gel molds are provided for forming the lanes in a gel plate, as well as a light module, for reading the bands present in the gel lanes with the photometer.