The Agilent 1100 G2258A Dual Loop Autosampler, Preparative Scale, is optimized for applications that require rapid injection of high sample volumes. Typically, these are preparative HPLC separations or sample trapping and enrichment methods. The dual loop concept with two preinstalled sample loops of different volume allows convenient switching between preparative scale and analytical scale applications without the need for hardware modifications. The sample tray can hold up to two well plates, vial plates or Eppendorf tube plates in any combination.
The Agilent 1100 G2258A Dual Loop Autosampler is a fixed loop sampler with two different sample loops. As a consequence of this design the metering device, also referred to as syringe, is not a part of the solvent flow path from pump to HPLC column. An additional flush solvent bottle is used to rinse this part of the hydraulic path after each injection. In order to minimize carryover, the sampler is equipped with a needle wash function which dips the needle into a wash vial or the wash port. The wash port is fed by a peristaltic pump and can be operated with most common HPLC solvents.
The needle seat assembly incorporates two independent needle seats. The front needle seat is used to fill the lower sample loop whereas the back seat is connected to the upper sample loop. The needle is fitted with a second shorter needle that vents the vial to the outside and guarantees rapid pressure equilibration between vial and ambient.