These basic lab tasks prove this LC team performs best. You can judge the quality of an LC system by the way it handles these basic laboratory challenges: quantitation, qualitative analysis and preparative capability. Which is where everything else in the field gives way to this quartet of Perkin-Elmer LC instruments. 1. The SERIES 3B solvent de livery system. The most sophisti cated around. Its dual pumps run independentlyon separate analy ses, or together on one analysis for faster throughput or solvent programming. Its flow rate range of 0.1-60 ml/min. is the widest anywhere. Retention times and peak height and/or areas are repeatable, so identification and quantitation are reliable even at the extremely low flow rates needed with high-speed micro columns. 2. The Model LC-75 spectro photometry detector. Its linearity over a wide dynamic range makes quantitative analysis reliable. Wavelength reset capability elim inates frequent recalibration and produces the highest analysis-toanalysis correlation. 3. The Model LC-75 Autocontrol. Used with the detector, it gives you the most advanced peak analysis system available today. Detection capability is between 190 and 600 nm. Get previously unob tainable qualitative data on submicrogram samples. Perform spectral scans, absorbance ratios, baseline correction, and automatic wavelength changes during a run. Wavelength resettability is ± 0.1 nm. 4. The SIGMA 10B Chromatog raphy Data Station. The computer that automates the system. You can set up different conditions for different samples, successive in
jections at different solvent con centrations, and different analytical wavelengths for different methods. The payoff shows up in these three vital tasks: Precise quantitation. This UV-Vis detection system stores baseline changes in mem ory during blank gradient runs and subtracts them from subse quent sample analyses. It flattens the baseline across the full range of detector sensitivity, improving quantitative analyses of complex mixtures. This chromatogram displays how the wide dynamic range of the system allows proper detection of both the strongest and weakest absorbing compounds in a single run. ι
1 Antioxidant Chromatogram Conditions C o l u m n : PE RP-8. 4.6 m m χ 2 5 cm Eluent: Gradient. 20-1009i,ACNin 5% aqueous H A c Flow:3ml/min D e t e c t i o n : UV @ 2 8 0 n m
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Spectroscopic analysis. Here's a run showing an extraction from a fat-soluble vitamin tablet. Chromatogram of Extracted Tablet for Fat-Soluble Vitamins
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Conditions C o l u m n : RP-8 M o b i l e Phase: 93.57» A in A + Β A = MeOH Β = 0.0O5 Hexanesulfonic A c i d in H2O PH2.8 Flow: 2 m l / m i n Detector: 265 n m S a m p l e : Extracted Tablet
To assure that peaks were correctly identified, stopped-flow spectra were obtained—for example, only the peak eluting at about 5.5 minutes exhibits the
strong absorbance at 266 nm which is characteristic of vitamin D. Fat-Soluble Vitamins: Stopped-Flow Spectrum of Vitamin D
Preparative capability. The system's unique gradient pre parative capability duplicates com plex analyses requiring gradient elution, and brings even further reductions in time and solvent consumption. Here, a 19-minute gradient run allowed resolution equal to that achieved with 45minute isocratic analyses, with one-sixth the solvent consumption! Gradient 4 0 ° C
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Don't put your money on an LC system that's less than you need. Our free literature kit covers the Perkin-Elmer LC hardware and technology in detail. Contact your Perkin-Elmer representative. Or write today. • Perkin-Elmer Corp., Analytical Instruments, Main Ave. (MS-12), Norwalk, CT 06856 U.S.A. • Bodenseewerk, Perkin-Elmer & Co., GmbH, Postfach 1120, 7770 Ueberlingen, Federal Republic of Germany. • Perkin-Elmer Ltd., Beaconsfield, Bucks HP9 1QA, England.
PERKIN-ELMER Responsive Technology Circle 180 for literature.
Circle 181 for a sales call. ANALYTICAL CHEMISTRY, VOL. 53, NO. 4, APRIL 1981 · 627 A
