PerkinElmer Autosampler

Product Details

PerkinElmer autosampler is a device that automatically brings samples to an instrument for analysis, allowing a much higher throughput than manual measurement. It is used with a variety of machines that perform chemical measurements, such as titrators, gas chromatographs, liquid chromatographs and water analyzers (like total carbon analyzers and dissolved inorganic carbon meters).

Most are designed for liquid analyses, and they include three basic components: a sample tray with indexing capability, a mechanism to transfer the sample from a sample vial to the injection loop, and an injection valve. A typical design uses a carousel mechanism with a series of circular sample trays that can be rotated until the desired one is below the injection needle. Each sample holder may contain individual sample vials or multi-well sample plates, with many having the capacity for hundreds of samples.

There are two basic types of apertor autosampler: push-to-fill and draw-to-fill. The former resembles manual injection, with the needle being indexed to a specific sample vial and puncturing its septum. Then, the syringe mechanism pumps to fill the needle with an amount of sample equal to the volume in the vial. The needle is then injected into the sample loop, completing the injection process.

The draw-to-fill autosampler, on the Perkinelmer autosampler other hand, draws the sample through tubing, which makes it a bit more like drawing a fluid from a container. A draw-to-fill autosampler has a reversible needle and can be operated in either the full-loop mode or the partial-loop mode. The latter mode is more common, as it allows a larger sample loop to be mounted and still allow the syringe mechanism to control the injection volume. Regardless of which type of autosampler you use, there is one weak point that can fail with time: the low-pressure needle seal. If the seal is not finger-tightened properly, it can leak and require replacement.