The FIAlab SIChrom is the first commercial Liquid Chromatography (LC) instrument based on the concept of Sequential Injection (SI). It combines the powerful sample processing capabilities of SI with the separation power of LC, thus offering a flow analyzer with unparalleled versatility.
The chief advantage that SIChrom holds over other LC devices is the ability to carry out automated sample pretreatment prior to separation and analysis. When equipped with suitable accessories, it can implement any of the pretreatment operations that our other SI instruments are capable of:
The chief advantage that SIChrom holds over other fluidic devices and analyzers is the ability to operate at elevated pressure. While most SI instruments are designed to handle max 50-100 psi back pressure, the SIChrom can tolerate over ten times that. When equipped with the standard 5 mL syringe, it can withstand 1,500 psi. With a 2.5 mL syringe, the upper pressure limit reaches all the way to 3,000 psi.
The SIChrom fluidic architecture consists of:
As all of FIAlab's analyzers, the SIChrom can be equipped with a detector (UV-VIS absorbance or fluorescence). The separation protocols and data collection are controlled by the SIAsoft software.
The most typical separation media used on the SIChrom are monolithic (e.g. Phenomenex Onyx™ or VWR Chromolith™) columns and core-shell (e.g. Sigma-Aldrich Ascentis Express™) columns.
Contact FIAlab to find out more about this unique solution for fluidics at elevated pressure.
Sequential Injection Chromatography examples:
SIC has been carried out on monolithic columns, using a medium pressure pump, or on microcolumns using a conventional low presure syringe pump. Since conceived only recently (Satinsky, Solich, Chocholous & Karlicek 2003), it is too soon to tell how wide a field of applications this novel technique will have. Yet, it is safe to assume that SIC will be accepted by the analytical community, since it provides numerous unexplored research opportunities. Unlike the conventional chromatographic techniques, SIC is based on programmable flow of the mobile phase, which allows convenient selection of injected sample volume and a simple formation of elution gradient. The apparatus comprises a bidirectional Leaders in Flow Injection Technology 2 www.flowinjection.com pump, holding coil, separation column, multiposition valve (MPV) and a detector. The assay protocol has the following steps: A) A precise volume of sample (red) is aspirated via MPV by flow reversal. Note that this allows change of injected sample volume without physical recombination of the injector. B) The MPV is switched towards the column and the flow is reversed. The injected sample zone passes through the column while analytes are retained. C) A precise volume of eluent is aspirated via MPV. D) Flow is reversed and a gradient of eluent is passed via MPV into the column. E) Separated analytes are measured as they flow through the detector. Flow programming also facilitates precolumn derivatization, allows generation of elution gradients, speeds up column regeneration and accelerates the assay by fast column flushing. Columns Since the flow programmable pumps are presently available only for moderate ( up to 500psi) or low pressures ( up to 75 psi) the choice of columns for SIC are limited to monolithic columns for moderate pressures or microcolumns for low pressure separations. Sol-Gel Monoliths are a novel type of HPLC columns manufactured by, e.g., Phenomenex and Merck. In contrast to conventional HPLC columns, the sol-gel monoliths are formed as a single piece of porous silica, having a higher porosity than conventional particulated columns. Merck reports a 15% greater porosity for their Chromolith columns over conventional columns. Consequently, column backpressure is substantially reduced allowing higher flow rates and faster throughputs. Monolith sol-gel columns show good separation performance at lower pressures, a critical feature that is integral to the SIChrom performance. Leaders in Flow Injection Technology 3 www.flowinjection.com Monolithic columns that use reverse phase are most popular and they have found many applications including separation of pharmaceuticals, proteins, oligonucleotides, organic acids, and enantiomeric compounds. Monoliths with ion exchanger sites found application in ion chromatography.
Don’t waste precious reagents. Don’t generate unnecessary waste. SIA can operate with miniscule volumes that will save you money and hassle.
Need to speed up your reaction? Add a heater. Need a chiller to cool your enzymatic reagents? Add a chiller. You can easily add components like these and others to any FIAlab instrument.
If you are performing chemical analysis at very pressures, the SIChrom is the instrument for you. Comfortably, reach pressures up to 3,000 psi.
Our SIA instruments, paired with SIAsoft, provide unique, cutting-edge solutions for on-line monitoring and process analytical technology (PAT). These solutions are used in research facilities, quality control labs, and manufacturing plants.
Sequential injection analysis is an intricate, dynamic analysis technique. The sheer number of actions, flow paths, and valves requires powerful computer control. As a result, we created SIAsoft. This new software packs a plethora of useful functions into a user-friendly interface. You can even use Python Scripting to build custom methods. Click below to find out more.