Flow Injection Analysis（流动注射分析）.pdfVIP

Leaders in Flow Injection Technology Flow Injection Analysis Almost all reagent based assays can be downscaled and automated by Flow Injection Analysis. FIA was first described in a patent filed in Denmark by Ruzicka and Hansen in 1974. Since then the technique has grown into a discipline covered by 22 monographs and over 20,000 research papers. The scope of the method grew from a tool for automation of serial assays to a method for enhancing the performance of spectroscopic and electrochemical instruments. The conventional FIA methodology, the Flow Injection (FI) is based on continuous flow, while its most recent variant, the Programmable Flow Injection uses different flow rates during individual steps of the assay protocol with aim to optimize the analytical readout. The second generation of FI techniques, the Sequential Injection (SI) also utilizes flow programming to optimize the assay protocol, but in contrast to FI it uses discontinuous flow generated by a syringe pump, and operates at microliter scale. The Conventional Flow Injection Method The conventional FI technique is based on injection of sample solution into a carrier solution that is continuously moving at a constant flow rate. The carrier stream transports the analyzed species through the reactor and into the detector. The assay protocol comprises the following steps: A) Sample injection is designed to meter an exact volume of analyte solution into a flowing stream of reagent. B) As the sample zone (red) moves downstream, the dispersion process mixes sample with reagent forming a reaction product (yellow). The extent of mixing and the length of reaction time is controlled by the flow rate, by channel volume, and by channel geometry. C) The reaction mixture flows through the detector yielding an analytical readout. Since all standards and samples to be analyzed are individually processed in exactly the sa