Analytical system and method including switching between liquid chromatography fluidic streams

An analytical system comprising a liquid chromatographic (LC) system comprising:

• a plurality of fluidic streams alternately connectable to a common detector via a stream-selection valve connected to the detector via a valve-to-detector conduit, wherein the analytical system further comprises a wash pump fluidically connected to the stream-selection valve and configured to connect to the valve-to-detector conduit between two consecutive fluidic streams in order to wash liquid from a previous fluidic stream out of the valve-to-detector conduit before liquid from a subsequent fluidic stream enters the valve-to-detector conduit,
• wherein the analytical system comprises a controller configured to manage a fluidic-stream connection time (t-Sn−1, T-Sn, t-Sn+1), that is the connection time between each fluidic stream (Sn−1, Sn, Sn+1) and the valve-to-detector conduit, and a wash-pump connection time (t-W), that is the connection time between the wash pump and the valve-to-detector conduit, by controlling switching of the stream-selection valve, and
• wherein the controller is configured to extend the wash-pump connection time while pumping of wash liquid through the valve-to-detector conduit in case of interrupted switching between fluidic streams or in case of system standby.

An automated analytical method comprising:

• alternately connecting a plurality of fluidic streams of a liquid chromatographic system to a common detector via a stream-selection valve connected to the detector via a valve-to-detector conduit, the method further comprising fluidically connecting a wash pump to the valve-to-detector conduit via the stream-selection valve between two consecutive fluidic streams and washing liquid from a previous fluidic stream out of the valve-to-detector conduit before liquid from a subsequent fluidic stream enters the valve-to-detector conduit,
• automatically managing a fluidic-stream connection time, that is the connection time between each fluidic stream and the valve-to-detector conduit, and a wash-pump connection time, that is the connection time between the wash pump and the valve-to-detector conduit, by controlling switching of the stream-selection valve, and
• adjusting a set of parameters of the detector and/or of an ionization source in case the detector is a mass spectrometer from a previous configuration related to the previous fluidic stream to a subsequent configuration related to the subsequent fluidic stream during the wash-pump connection time before switching to the subsequent fluidic stream.

An automated analytical method comprising alternately connecting a plurality of fluidic streams of a liquid chromatographic system to a common detector via a stream-selection valve connected to the detector via a valve-to-detector conduit, the method further comprising fluidically connecting a wash pump to the valve-to-detector conduit via the stream-selection valve between two consecutive fluidic streams and washing liquid from a previous fluidic stream out of the valve-to-detector conduit before liquid from a subsequent fluidic stream enters the valve-to-detector conduit,

• automatically managing a fluidic-stream connection time, that is the connection time between each fluidic stream and the valve-to-detector conduit, and a wash-pump connection time, that is the connection time between the wash pump and the valve-to-detector conduit, by controlling switching of the stream-selection valve, and
• extending the wash-pump connection time while pumping of wash liquid through the valve-to-detector conduit in case of interrupted switching between fluidic streams or in case of system standby.

An automated analytical method comprising:

• alternately connecting a plurality of fluidic streams of a liquid chromatographic system to a common detector via a stream-selection valve connected to the detector via a valve-to-detector conduit, the method further comprising fluidically connecting a wash pump to the valve-to-detector conduit via the stream-selection valve between two consecutive fluidic streams and washing liquid from a previous fluidic stream out of the valve-to-detector conduit before liquid from a subsequent fluidic stream enters the valve-to-detector conduit,
• automatically managing a fluidic-stream connection time, that is the connection time between each fluidic stream and the valve-to-detector conduit, and a wash-pump connection time, that is the connection time between the wash pump and the valve-to-detector conduit, by controlling switching of the stream-selection valve, wherein the method comprises
• comparing a liquid pressure between the wash pump and the stream-selection valve determined during the wash-pump connection time with a liquid pressure determined when the wash pump is fluidically connected to waste and based on such comparison determining whether there is a clogging in the valve-to-detector conduit.