Methods and apparatus for analysis of complex mixtures

A sample analysis system, comprising:

• a sample analysis instrument;
• a thermal desorption unit including a body providing a desorption chamber, a removable end cap for closing the chamber, a desorber heating system arranged to heat the desorption chamber, a gas inlet to the desorption chamber, and a gas outlet from the desorption chamber;
• a valve assembly structured and arranged to operate in a run mode wherein the valve assembly directs a flow of carrier gas to the thermal desorption unit gas inlet, and couples the thermal desorption unit gas outlet to an inlet of the sample analysis instrument, and also structured and arranged to operate in a flush mode wherein the valve assembly directs the flow of carrier gas to the inlet of the gas analysis instrument, directs a flow of flushing gas to the thermal desorption unit gas inlet, and couples the thermal desorption unit gas outlet to an exhaust, wherein the valve assembly includes a multi-port valve, a first port being coupled to a carrier gas supply, a second port being coupled to the thermal desorption unit gas inlet, a third port being coupled to the thermal desorption unit gas outlet, a fourth port being coupled to the sample analyzer gas inlet, a fifth port being coupled to a purge gas supply, and a sixth port being coupled to the exhaust.

A sample analysis system comprising:

• a sample analysis instrument;
• a thermal desorption unit including a body providing a desorption chamber, a removable end cap for closing the chamber, a desorber heating system arranged to heat the desorption chamber, a gas inlet to the desorption chamber, and a gas outlet from the desorption chamber, wherein the end cap is structured and arranged to introduce a sample into the desorption chamber without opening the desorption chamber to atmosphere;
• a valve assembly structured and arranged to operate in a run mode wherein the valve assembly directs a flow of carrier gas to the thermal desorption unit gas inlet, and couples the thermal desorption unit gas outlet to an inlet of the sample analysis instrument, and also being structured and arranged to operate in a flush mode wherein the valve assembly directs the flow of carrier gas to the inlet of the gas analysis instrument, directs a flow of flushing gas to the thermal desorption unit gas inlet, and couples the thermal desorption unit gas outlet to an exhaust.