Abstract: The present invention relates to an induction heating cooker for supplying a predetermined resonant current to a heating coil to thereby carry out a cooking operation, the induction heating cooker including: a rectifying unit for full wave rectifying a commercial alternating current, a zero voltage detecting unit for detecting a zero potential of the commercial alternating current, a control unit for synchronizing with the zero potential of the commercial alternating current detected by the zero voltage detecting unit to thereby control the overall operations of the induction heating cooker, a variable frequency oscillating unit for receiving a control signal generated by the control unit to thereby generate an oscillating frequency, an inverter driving unit for generating a driving signal to thereby drive the switching element according to the oscillating frequency generated by the variable frequency oscillating unit, an inverter for receiving the direct current voltage generated from the rectifying unit acc

Abstract: Disclosed herein is a process for purifying hirudin from a solution containing hirudin and other substances, characterized in that the process comprises a step of subjecting the solution to a metal ion affinity chromatography wherein copper ion (Cu.sup.++) is used as a metal ion and a phosphate buffer is used as an eluent.