gc columns

GC COLUMNS | HIGH-PERFORMANCE RXI COLUMNSRxi® Columns OverviewFigure 3 An Rxi®-5ms column givesthe highest response for both basicand acidic compounds.Response Factor (RF)Response Factor (RF)1.0000.8000.6000.4000.2000.0000.3000.2500.2000.1500.1000.0500.0002 ng of pyridineRxi-5msRxi-5msZB-5ZB-5 MSVF-5msHP-5msDB-5msDB-5Column2 ng of 2,4-dinitrophenolZB-5ZB-5 MSVF-5msHP-5msDB-5msDB-5ColumnComparison of 30m x 0.25mm ID, 0.25μmcolumns.Innovation & Service“When my research group needed aGC column for a chiral separation,Restek was the only company thatoffered to provide us with testcolumns to evaluate. The willingnessof Restek to work with us to find asolution to our separation problem isexceptional.”Joe Dinnocenzo,Professor of ChemistryDirector, Center forPhotoinduced Charge TransferUniversity of RochesterFigure 2 Analyte levels in samples are unknown; only inert columns, which preventconcentration from affecting retention time, can assure accurate results.A: Pyridine on non-Rxi® columnB: Pyridine on-Rxi® columnRetention times vary withconcentration; poor peakshape requires manualintegration and additionalreview.2.10 2.20 2.30 2.40 2.50 2.60 2.70 2.80 Time.GC_EX0111810 ng, 2.26 min.2.5 ng, 2.28 min.1.0 ng, 2.32 min.extracted ion chromatogram, m/z 792.25 2.30 2.35 2.40 2.45 2.50 2.55 2.60 Time.GC_EX01119Predictable retentiontimes, regardless ofconcentration; easy,accurate integration.10 ng, 2.39 min.1 ng, 2.40 min.0.5 ng, 2.41 min.Improved Response for Difficult CompoundsAnother reason column inertness is important for trace-level analysis is that many acidic,basic, and polar compounds will tail significantly and become difficult to analyze if the columncontains active sites. The remarkable neutrality of Rxi® columns solves this problemand allows a wide range of compounds to be analyzed with high sensitivity, often on a singlecolumn. All Rxi® columns are exceptionally inert as demonstrated in Figure 3 by highresponse factors for both pyridine (basic) and 2,4-dinitrophenol (acidic). Rxi® columns reliablyproduce highly symmetric peaks and improved responses for difficult compounds,indicating greater inertness than columns produced by other manufacturers (Figure 4).Figure 4 Rxi® columns are the most inert columns on the market providingthe most symmetric peak shape for basic compounds, such as pyridine.DB-5ZB-5ZB-5msRxi ® -5msDB-5msSymmetric peaks give high responseand predictable retention times.VF-5msHP-5msHow can we help you today?Contact support@restek.com or yourlocal Restek representative for helpful,knowledgeable technical support.Comparison of 30m x 0.25mm ID, 0.25µm 5% diphenyl columns, 2ng pyridine on-column, helium carrier gas,Oven temp.: 50°C (3 min.) to 180°C @ 35°C/min. (5 min.), Det.: FID @ 250°C38 www.restek.comWebsite : www.chromtech.net.au E-mail : info@chromtech.net.au TelNo : 03 9762 2034 . . . in AUSTRALIA Mar 2011