A system for dispensing radioactive liquids, the system comprising: a radiation containment chamber including an enclosure constructed of a radiation shielding material; and a liquid dispensing apparatus at least partly disposed in an interior of the enclosure, the liquid dispensing apparatus including: a support arm rotatable about a rotation axis; an actuator operatively connected to the support arm and configured to at least one of rotate the support arm about the rotation axis and displace the support arm in a direction parallel to the rotation axis; a pipette assembly mounted to the support arm, the pipette assembly including a pipette tip defining an opening through which liquids are aspirated and dispensed, a piston, and a stepper motor operatively connected to the piston to control linear displacement of the piston; and a controller connected to the stepper motor and configured to control the stepper motor to control displacement of the piston, wherein the controller is configured to determine a number of steps by which to rotate the stepper motor based on a non-linear relationship between a volume of liquid aspirated or dispensed by the pipette assembly and a corresponding number of steps by which the stepper motor is rotated. a radiation containment chamber including an enclosure constructed of a radiation shielding material; and a liquid dispensing apparatus at least partly disposed in an interior of the enclosure, the liquid dispensing apparatus including: a support arm rotatable about a rotation axis; an actuator operatively connected to the support arm and configured to at least one of rotate the support arm about the rotation axis and displace the support arm in a direction parallel to the rotation axis; a pipette assembly mounted to the support arm, the pipette assembly including a pipette tip defining an opening through which liquids are aspirated and dispensed, a piston, and a stepper motor operatively connected to the piston to control linear displacement of the piston; and a controller connected to the stepper motor and configured to control the stepper motor to control displacement of the piston, wherein the controller is configured to determine a number of steps by which to rotate the stepper motor based on a non-linear relationship between a volume of liquid aspirated or dispensed by the pipette assembly and a corresponding number of steps by which the stepper motor is rotated. a support arm rotatable about a rotation axis; an actuator operatively connected to the support arm and configured to at least one of rotate the support arm about the rotation axis and displace the support arm in a direction parallel to the rotation axis; a pipette assembly mounted to the support arm, the pipette assembly including a pipette tip defining an opening through which liquids are aspirated and dispensed, a piston, and a stepper motor operatively connected to the piston to control linear displacement of the piston; and a controller connected to the stepper motor and configured to control the stepper motor to control displacement of the piston, wherein the controller is configured to determine a number of steps by which to rotate the stepper motor based on a non-linear relationship between a volume of liquid aspirated or dispensed by the pipette assembly and a corresponding number of steps by which the stepper motor is rotated.