Patent ID: 11860143
Assignee: DIONEX CORPORATION
Field: Measurement (Instruments)
Classification: CPC G  B | IPC G

Claim 14:
15. A system for self-regulating the separation of ionic species in a liquid sample comprising:
an ion chromatography suppressor including a liquid-sample channel, an ion-receiving channel, and an ion-exchange membrane configured to substantially block bulk liquid flow between the liquid-sample and ion-receiving channels while allowing passage of ions of one charge, positive or negative, between the channels;
first and second electrodes in electrical communication with the liquid-sample and ion-receiving channels, respectively;
a power supply for applying an electric potential to the suppressor via the first and second electrodes; and
a control unit including one or more processors and memory, wherein the one or more processors run software configured to perform the following steps:
setting the power supply to provide an offset voltage VOS to the suppressor;
activating the power supply to provide an applied voltage VA to the suppressor in addition to the offset voltage VOS;
commencing an ion chromatography run in which an eluent flows through the suppressor;
measuring a current of the suppressor responsive to the offset and applied voltages VOS and VA during the ion chromatography run;
determining a suppressor state of the suppressor based upon the measured current in response to the offset voltage; and
adjusting the offset voltage VOS based upon the suppressor state, wherein (a) offset voltage VOS is increased for an unsuppressed state, and (b) offset voltage VOS is maintained for a suppressed state.