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PL-ELS 2100

PL-ELS 2100 IceN EW

PL-ELS 1000

Now a part of Varian, Inc.


Detect Everything You Inject with High SensitivityIt is well recognized that Evaporative Light Scattering Detection (ELSD) can outperform traditional detectors when analyzing non-chromophoric samples by HPLC as the detection method does not rely on the optical properties of the analyte. Furthermore, an ELSD detects all compounds less volatile than the mobile phase and, with advanced design features for low temperature operation, the benefits of ELSD compared to UV or refractive index detection now apply to an even wider range of HPLC applications. Evaporative Light Scattering Detectors from Polymer LaboratoriesPolymer Laboratories (PL), now a part of Varian, Inc., is a world leader in the design, build, service and support of evaporative light scattering detectors with over 17 years experience in this field. PLs instruments have evolved, and continue to develop, through listening to the requirements of our customers. Polymer Laboratories presents three models of ELSD, each offering high sensitivity for a wide range of analytes and analysis conditions, and each designed to address your particular application area. Choose from the PL-ELS 2100 for regular HPLC, the new sub-ambient PL-ELS 2100 Ice (Integrated Cooled Evaporator) for the detection of very low boiling point compounds or the PL-ELS 1000 for routine HPLC and GPC. Whichever option you choose, PL will deliver you high quality, high sensitivity, state of the art evaporative light scattering detection. Designed and built to the highest standards, Polymer Laboratories detectors offer considerable benefits compared to other ELSDs on the market: Extremely small footprint to maximize available bench space Wide gradient compatibility, no limitation on choice of solvents High sensitivity, extremely low limits of detection (LoD) Wide application range to cover very low to high molecular weight compounds Low dispersion, minimal peak broadening for maximum resolution Rapid equilibration, fast set-up and high productivity Advanced, easy to use instrument control with built-in safety

ELSD detectors from PL offer the widest flexibility and deliver optimum performance for all applications.

Universal ResponseELSD does not rely on the optical properties of the analyte making it an ideal detector for many compounds, including those with no UV chromophore or widely differing extinction coefficients. When UV detection is used to monitor the separation of equal amounts of aspirin and phenacetin, different responses are recorded due to variable extinction coefficients at 280nm. Clearly, a more uniform response is obtained when the PL-ELS detectors are used.Sample: Column: Eluent: Flow Rate: Detectors: 1. Aspirin, 2. Phenacetin PLRP-S 100 5m, 150x4.6mm 0.1% TFA in 50% Water : 50% ACN 0.5ml/min PL-ELS 2100 (neb=30C, evap=30C, gas=1.6 SLM) UV, 280nm 2

PL-ELS 2100

PL-ELS 2100 Ice

PL-ELS 1000

PL-ELS 2100 PL-ELS 2100 PL-ELS 1000 PL-ELS 2100 Ice PL-ELS 1000 PL-ELS 1000HPLC analysis of non-volatile compounds HPLC analysis of semi-volatile compounds Ambient GPC analysis High temperature GPC analysis

KEY 1. Aspirin 2. Phenacetin


Analytical Techniques HPLC - analytical, microbore, preparative LC-MS High throughput screening GPC/SEC High temperature GPC TREF GPEC

Application Areas Pharmaceuticals Nutraceuticals Combinatorial libraries Carbohydrates Lipids Phospholipids Triglycerides Fatty acids Amino acids Polymers Surfactants0 min 10 PL-ELS 2100 UV, 280nm





ELSD - The Ideal Substitute for, or Supplement to, Your Existing HPLC DetectorsEvaporative light scattering detection has become a regular detection method for liquid chromatography, offering key benefits over more conventional UV and RI detectors: Does not require the sample to have a chromophore Universal response, no effect of extinction coefficient or dn/dc Fully gradient compatible, no limitation on solvent choice Better alternative to UV detection at low wavelengths No need for pre- or post-column derivatization Excellent baseline stabilityCompounds: Sample: Column: Eluent A: Eluent B: Gradient: Flow Rate: Inj Vol: Detectors: 1. Cimiracemoside, 2. Actein, 3. 27-deoxyactein Black Cohosh Tablet Inertsil C18 5m, 150x4.6mm 0.1% Formic acid in Water ACN 30-40% B in 30 mins, 40-60% B in 30 mins 1.0ml/min 20l PL-ELS 2100 (neb=30C, evap=50C, gas=1.4 SLM) UV, 230nm 1

Better Alternative to UV Detection at Low WavelengthsEvaporative light scattering detection is a more favorable alternative than UV detection for the analysis of compounds that require low wavelength analysis (e.g. 230nm) or possess a weak chromophore. These compounds have a low sensitivity to UV detection and suffer from baseline instability under gradient elution. The benefit of ELSD for these types of compounds is highlighted in Figure 1, which compares UV and ELS detection for the analysis of a black cohosh sample.

DMSO Transparency for High Throughput ScreeningThe vast majority of combinatorial libraries screened by high throughput methods are stored in Dimethylsulfoxide (DMSO). UV and Mass Spectrometry will miss potential drug compounds that have no UV chromophore, so ELSD is commonly used. However, at the low evaporator temperatures required to detect volatile components, the presence of DMSO in the sample can mask the response of early eluting compounds. In the PL-ELS 2100, the addition of a carefully controlled stream of gas to the evaporation step enables complete removal of the DMSO to take place without increasing the operating temperature. The benefits of this DMSO transparency are highlighted in the figure below.

KEY 1. Cimiracemoside 2. Actein 3. 27-deoxyactein



PL-ELS 2100

UV, 230nm




A Valuable Addition to Your LC-MS SystemDMSO

The DMSO response masks the fast eluting peak

As the operational requirements are very similar, methods developed on PLs evaporative light scattering detectors can be directly transferred to MS, saving valuable LC-MS method development time. ELSDs from Polymer Laboratories can be used in parallel with any standard LC-MS system to obtain concentration information for all compounds, whether they are UV active or not.Samples: Column: Eluent A: Eluent B: Gradient: Flow Rate: Inj Vol: Detectors: KEY 1. Verapamil 2. Diazepammin 15

gas=1.2 SLM

Increasing the gas flow to 1.8 SLM gives DMSO transparency

1. Verapamil 2. Diazepam Commercially available C8 3m, 150x2.1mm 0.1% Formic acid in Water 0.1% Formic acid in ACN 20-80% B in 5 mins 0.3ml/min 10l MS, UV, PL-ELS 2100 (neb=50C, evap=50C, gas=1.6 SLM)

gas=1.8 SLM 0

2 1MS

Sample: Column: Eluent A: Eluent B: Gradient: Flow Rate: Inj Vol: Detector:

2mg/ml in DMSO Inertsil 7 ODS-3 5m, 150x4.6mm 0.1% HFBA in Water 0.1% HFBA in ACN 5-30% B in 10 mins, 30-80% B in 5 mins 1.0ml/min 20l PL-ELS 2100 (neb=25C, evap=25C, gas as shown)

LC-MS trace shows 1:3 ratio

UV trace shows 1:10 ratio


ELS shows the true ratio of 1:1

PL-ELS 2100



ELSDs from Polymer Laboratories - Better By DesignEvaporative light scattering detection involves a three stage process:

Easy and Safe to UsePLs detectors offer both onboard operation via a keypad and display or advanced instrument control using a Windows PC based graphical user interface. Up to 10 pre-set methods can be stored, and the control software provides the facility for automation and logging procedures. In addition, the control software can be used to run a series of diagnostic checks to test for system compliance and validate performance, as well as to provide interaction with the multiple safety features built into the detectors.

NebulizationEfficient nebulization using low gas flow rates is a feature of PLs detectors. Independent nebulizer temperature control and digital gas flow control provide excellent stability and reproducibility. Any poorly nebulized eluent is removed via a drain port to minimize baseline noise.

EvaporationThe nebulized stream passes through an independently temperature controlled evaporator tube where the solvent is removed, leaving the less volatile solute particles. PLs detectors feature the shortest evaporator tubes resulting in extremely low swept volume and minimum peak dispersion. The result is that evaporative light scattering detectors from Polymer Laboratories deliver you the maximum resolution from your separation, especially important for work with small column volumes.

gas inlet


Instrument Qualification - IQ, OQAll Polymer Laboratories detectors are rigorously tested to a high specification before they are shipped, and detailed IQ, OQ documentation is included with each unit. In addition, PLs detectors can be incorporated into any HPLC system, and a complete Qualification Workbook is provided to assist you.

eluent inlet light source liquid waste

Optical DetectionThe solute particles are detected as they pass through the optical chamber. Advanced design of the optical and electronic components ensures that PLs detectors deliver maximum sensitivity with minimum baseline noise.Sample: Column: Eluent A: Flow Rate: Inj Vol: Detector: Fentanyl Commercially available C18 5m, 50x2.1mm 60% 0.25M Ammonium acetate in Water, 40% ACN 0.25ml/min 10l PL-ELS 2100 (neb=40C, evap=70C, gas=1.2 SLM)

Galaxie Control and Data Hand

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