The fully automated ProfiBlot 48 western blot processor can handle up to 48 samples each run in a disposable tray within an enclosed environment, thereby minimizing the user's exposure to potentially infectious samples. Auto-calibration of dispense volumes eliminates tedious manual procedures, and hazardous waste is collected separately, minimizing waste treatment costs. The system includes a predefined cleaning protocol for ease of maintenance. ProfiBlot 48 complies with Directive 98/79/EC-IVD.