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Detect Everything You Inject With the PL-ELS 2100 Evaporative Light Scattering Detector. First Impressions. Compact, modern design Flat top Small footprint, stackable Operation via control panel and simple keypad Column connection at front of detector
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Detect Everything You Inject With the PL-ELS 2100Evaporative Light Scattering Detector
First Impressions • Compact, modern design • Flat top • Small footprint, stackable • Operation via control panel • and simple keypad • Column connection at front • of detector • One exhaust tube at rear, • one liquid waste port at front
PL-ELS 2100 Front Panel Detail 200mm 200mm Display Keypad 415mm Column Connection Liquid Waste 450mm 450mm
Principle of Operation • The ELSD principle of operation employs three distinct stages : • Nebulization • Evaporation • Detection Gas Eluent Inlet Light Source Liquid Waste
Nebulization • Eluent flow mixed with N2/Air • Concentric nebulizer gives efficient nebulization, stable droplet plume, uniform droplet size • Narrower cone of spray plume allows a smaller nebulizer chamber, which minimizes band broadening • Better recovery of semi-volatile solutes compared to cross-flow nebulizer • Easier to align, reproducible from one detector to another • Temperature independently controlled
Evaporation • Solvent removed by heating • Temperature independently controlled • PL-ELS 2100 has an additional gas input that aids evaporation (patent pending) • Small volume evaporator • Fast thermal equilibration • Diffuser reduces turbulence inside evaporator tube which minimizes band broadening (patented)
Detection • Blue LED light source (480nm) • Intensity controllable by user • Photomultiplier detector tuned to same wavelength for increased sensitivity • Feedback control for light source provides constant output • Detector mounted directly onto the optics which eliminates stray light loss and increases sensitivity • Reduced volume in the optics chamber, minimizes band broadening • Digital gain control to optimize full scale sensitivity • Digital signal smoothing to optimize S/N ratio
Advantages of Evaporative Light Scattering Detection • Universal: responds to all compounds in the mobile phase. • -Detects compounds that do not possess a UV chromophore • e.g. polymers, sugars
Advantages of Evaporative Light Scattering Detection: Pharmaceutical Mixture • Detects all components in a single run Samples : 1. α-cyclodextrin 2. ß-cyclodextrin 3. Ibuprofen Column: Aquasil C18 5µm, 150x4.6mm Eluent A: Water Eluent B: Acetonitrile Gradient: 50-95% B in 5 mins Flow Rate: 1.0 ml/min Inj Vol: 20µl Detector: PL-ELS 2100 (neb=30°C , evap=50°C, gas=1.0 L/min) ELSD UV @ 220nm
Advantages of Evaporative Light Scattering Detection • Universal: responds to all compounds in the mobile phase -Detects compounds that do not possess a UV chromophore e.g. polymers, sugars • Not dependent on spectroscopic properties of compound: -Produces more uniform detection sensitivity for analytes
Advantages of Evaporative Light Scattering Detection: Uniformity of Response Comparison of UV and ELS traces show that ELSD allows for a more uniform response than UV detection Column: PLRP-S 100Å 5µm, 150 x4.6mm Eluent A: 50% 0.1% TFA in Water : 50% 0.1% TFA in ACN Flow Rate: 1.0ml/min Inj Vol: 10µl Detector: PL-ELS 2100 (neb=30°C, evap=30°C, gas=1.4 L/min) UV-VIS @ 280nm
Advantages of Evaporative Light Scattering Detection • Universal: responds to all compounds in the mobile phase • Detects compounds that do not possess a UV chromophore e.g. polymers, sugars • Not dependent on spectroscopic properties of analyte: -Produces more uniform detection sensitivity for analytes • Not susceptible to baseline drift during gradient elution, temperature or solvent pump fluctuations • ELSD compatible with a much wider range of solvents compared to RI and UV
Fast Gradient, Fast Flow Rate Capability Sample: Indapamide (IND), Dibutyl phthalate (DBP) Column: PLRP-S 100Å 5µm, 50x4.6mm Eluent A: 0.05% TFA in Water Eluent B: 0.05% TFA in ACN Gradient: 5-95% B in 1 min Flow Rate: Increased from 2ml/min up to 5ml/min Detector: PL-ELS 2100 (neb=30°C, evap=30°C, gas=1.6 L/min) Note : IND is non-volatile, DBP is relatively volatile
DBP IND 2ml/min 3ml/min 4ml/min 5ml/min min Fast Gradient, Fast Flow Rate Capability
2ml/min 3ml/min 4ml/min 5ml/min Fast Gradient, Fast Flow Rate Capability • Stable baseline throughout the gradient • PL-ELS 2100 can operate in 100% up to 5ml/min min
Advantages of Evaporative Light Scattering Detection: Ideal Complement to LC-MS • Similar operating principles to LC-MS - Volatile buffers - Favors lower flow rates (i.e. 0.2-0.5 ml/min) • Can develop LC methods on PL-ELS 2100 then transfer to LC-MS • ELSD can provide supporting information when used in tandem with LC-MS
Ideal Complement to LC-MS Sample Mixtureof known 1:1 ratio LC-MS results show ratio to be 3:1 UV-Vis result show ratio to be 10:1 PL-ELS 2100 results show ratio to be 1:1 (Response independent of optical properties)
PL-ELS 2100 Sensitivity - Limit of Detection Column: C18 5µm,150x4.6mm Eluent A: 99% Water + 0.1 % TFA Eluent B: 1% ACN + 0.1% TFA Flow Rate: 0.5ml/min Detector: PL-ELS 2100 (neb=50°C, evap=70°C, gas=1.2 L/min) Sample: DL-Glutamic Acid
PL-ELS 2100 Sensitivity - Limit of Detection • LOD improved with lower eluent flow rates and smaller ID column Caffeine Loading 100ng 4.6 ID S/N = 4.4 Caffeine Loading 30ng 2.1 ID S/N = 11.5
Mode Current method Actual values of set parameters Detector output Status Interactive menu bar Keypad Operating the PL-ELS 2100: Onboard Instrument Control
Simple Operation • Two modes of operation : • STANDBY • Power on • LED off • Heaters off • Gas at minimum flow rate (1.2 L/min) -Gas shuts off after 15 minutes RUN • Power on • LED on • Temperatures and gas flow controlled to set values
Digital Signal Processing • Digital Signal functions are accessed via the down arrow key in main menu screen • Parameter Screen allows you to change -PMT output or gain (1-250) - Smoothing (1-50) - LED intensity (0-100)
PL-ELS 2100 Control Software • Select mode of operation • Control parameters • Evaporator & Nebulizer temp • Gas flow (0-3.25 L/min) • Monitor output • Gain setting (0.1-250) • Signal smoothing (0-5) • Log instrument conditions over time • Load / Edit methods • -10 programmable methods
PL-ELS 2100 Control Software • Supplied as standard with the PL-ELS 2100 • Select 1 of 10 different temperature programs according to analysis • Also available as a Software Development Kit for third party system integration • To use the control software simply connect the PL-ELS 2100 to a PC via a serial connection (RS232) on selectable COM port • Where no serial port is available, a USB serial connector can be used
PL-ELS 2100 Method Manager Software • Used when the instrument is to be controlled via the onboard instrument control (rather than software control) • This is a simple software utility designed to set up, edit and log defined methods which can then be downloaded to the • PL-ELS 2100 • Method Manager Software supplied as standard with the • PL-ELS 2100 • To use this software utility, simply connect the PL-ELS 2100 to a PC via a serial connection (RS232)
PL-ELS 2100: Routine Operation • When running with the “XXX” method, the User has complete flexibility to change parameters via the PL-ELS 2100 keypad and display (e.g. for method development) • Once standard methods for operation of the PL-ELS 2100 have been established, these can be stored using the PL-ELS 2100 Method Manager software utility and downloaded to the unit • These downloaded parameters are stored as numbered methods (1-10) and cannot be edited through the keypad, only by running the PL-ELS 2100 Method Manager software
A New Approach to ELS Detection • Operating conditions of the PL-ELS 1000 is based on the properties of the eluent (e.g. high boiling point solvents require high evaporator temperatures) • However, the PL-ELS 2100 operating conditions are determined by the properties of the analyte (e.g. semi-volatile or non-volatile) • The PL-ELS 2100 can evaporate water at ambient temperature, unlike the PL-ELS 1000.
Manipulating the PL-ELS 2100 Parameters • FOR NON-VOLATILE SOLUTES • Nebulizer and evaporator can run hot to increase signal to noise ratio • Gas flow is set as low as possible to maximize signal • FOR RELATIVELY VOLATILE SOLUTES • Nebulizer and evaporator run cold to increase signal • Gas flow is increased to control baseline noise
Volatile Applications: Effect of Changing Evaporator Temperature Samples: 1. Acetanilide, 2. Indapamide, 3. Ibuprofen, 4. Dibutylphthalate Column: C18 5µm, 150x4.6mm Eluent A: 0.1% TFA in Water Eluent B: 0.1% TFA in ACN Gradient: 60-90%B in 5 mins Flow Rate: 1.0mL/min Detector: PL-ELS 2100 (neb and evap set at the same temperature, gas 1.8 L/min) Note: peak 2 is non-volatile, peaks 1, 3, 4 are relatively volatile
Volatile Applications: Effect of Changing Evaporator Temperature • At high temperature peak 2 has better S/N but peaks 1,3,4 are not detected • At 30°C all four peaks are detected
Environmental Application:Herbicides Sample: Mixture of 10 Phenylurea herbicides Column: C18 5µm, 250x4.6mm Eluent A: Water Eluent B: Acetonitrile Gradient: 10-80%B in 40 mins Flow Rate: 0.7ml/min Inj Vol: 20µl Detector: PL-ELS 2100 (neb=25°C, evap & gas flow varied)
Non-Volatile Applications: PEG 400 Separation Sample: PEG 400 Column: PLRP-S 100Å 5µm, 150x4.6mm Eluent A: Water Eluent B: ACN Gradient: 10-30% B in 12 mins Flow Rate: 1.0mL/min Inj Vol: 10µl
PEG 400: Effect of Changing Temperature Higher temperatures increase S/N, no risk of loss due to evaporation Evap 90°C Neb 90°C Gas 1.6 L/min Evap 30°C Neb 30°C Gas 1.6 L/min
PEG 400: Effect of Changing Gas Flow Sensitivity is improved as gas flow is reduced Evap 70°C Neb 50°C Gas 1.2 L/min Evap 70°C Neb 50°C Gas 2.4 L/min
Non-Volatile Application: Triglycerides in Natural Oils Sample: 2mg/ml Starflower Oil Column: C18 5µm, 250x4.6mm Eluent A: ACN Eluent B: DCM Gradient: 30-50% B in 40 mins; 50-90% in 2 mins, hold for 3mins Flow Rate: 1.0ml/min Inj Vol: 20µl Detector: PL-ELS 2100 (neb=40°C, evap=70°C, gas=1.4 L/min)
Supercritical Fluid Chromatography: PEG Separation Sample: PEG 1000 Column: Berger SFC Diol Column 60Å 6µm, 250x4.6mm Eluent: Carbon Dioxide with 5% Methanol Flow Rate: 2ml/min, Pressure: Carbon Dioxide was pressure programmed from 100bar to 250bar at 10bar/min. Inj Vol: 10µl Detector: PL-ELS 2100 (neb=40°C, evap=30°C, gas=0.9 L/min)
Supercritical Fluid Chromatography PEG Separation Reduced band broadening allows high resolution SFC separations to be performed PEG 1000
PL-ELS 2100:DMSO Transparency Sample: Pharmaceutical Mixture in DMSO Column: C8 5µm, 50x4.6mm Eluent A: Water Eluent B: Acetonitrile Gradient: 5-100% B in 5 mins Flow Rate: 1.0ml/min Inj Vol: 20µl Detector: PL-ELS 2100 (neb=25°C, evap & gas flow varied)
PL-ELS 2100 DMSO Transparency:Ideal for High Throughput Screening Loss of volatile species occurs as temperature is increased
PL-ELS 2100: DMSO Transparency:Ideal for High Throughput Screening • The design of the PL-ELS 2100 makes it transparent to DMSO at 25-30°C • Great potential in the High Throughput Combichem market • Unique to the PL-ELS 2100 due to its use of evaporation gas PL-ELS 2100: neb=25°C, evap=30°C
Benefits of Evaporative Light Scattering Detection • Universal detector: independent of the optical properties of the solute • Compatible with gradient elution • Ideal for fast gradient elution:- no solvent front. Removes the need for derivatization • Compatible with chromatographic techniques such as MS and SFC • Wide application area
Additional Benefits of the PL-ELS 2100 • Operation in 100% water at 25°C • DMSO transparency at ambient temperature • Extremely low dispersion for high resolution separations (e.g. SFC) • High sensitivity to volatile compounds • Compatible with eluent flow rates, up to 5ml/min • Rapid thermal equilibration • Easy to use • Extremely small footprint, stackable