detect everything you inject with the pl-els 2100 evaporative light scattering detector

Detect Everything You Inject With the PL-ELS 2100

Evaporative Light Scattering Detector

2

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

3

PL-ELS 2100 Front Panel Detail

200mm

450mm

200mm

Column Connection

Liquid Waste

Keypad415mm

Display

450mm

4

Principle of Operation

The ELSD principle of operation employs three distinct stages :

• Nebulization

• Evaporation

• Detection

Eluent Inlet

Gas

Liquid WasteLight Source

5

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

6

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)

7

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

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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

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Advantages of Evaporative Light Scattering Detection: Pharmaceutical Mixture

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)

• Detects all components in a single run

ELSD

UV @ 220nm

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• 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

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Column: PLRP-S 100Å 5µm, 150 x4.6mmEluent A: 50% 0.1% TFA in Water : 50% 0.1% TFA in ACNFlow Rate: 1.0ml/minInj Vol: 10µlDetector: PL-ELS 2100 (neb=30°C, evap=30°C, gas=1.4 L/min) UV-VIS @ 280nm

Comparison of UV and ELS traces show that ELSD allows for a more uniform response than UV detection

Advantages of Evaporative Light Scattering Detection: Uniformity of Response

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• 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

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Fast Gradient, Fast Flow Rate Capability

Sample: Indapamide (IND), Dibutyl phthalate (DBP)

Column: PLRP-S 100Å 5µm, 50x4.6mmEluent A: 0.05% TFA in WaterEluent B: 0.05% TFA in ACNGradient: 5-95% B in 1 minFlow Rate: Increased from 2ml/min up to 5ml/minDetector: PL-ELS 2100 (neb=30°C, evap=30°C,

gas=1.6 L/min)

Note : IND is non-volatile, DBP is relatively volatile

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gds 17feb03-0048.cgrm (ELS 2100 #0005 onchannel 4)




Res

pons

e

Minutes

2.0

111.6

221.2

330.8

440.4

550.0

0 1 2 3

2ml/min

3ml/min

4ml/min

5ml/min

IND

DBP

min

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Response

Minutes

4.0

5.8

7.6

9.4

11.2

13.0

0.0 0.6 1.2 1.8 2.4 3.0

2ml/min

3ml/min

4ml/min

5ml/min

• Stable baseline throughout the gradient

• PL-ELS 2100 can operate in 100% up to 5ml/min

min

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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

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Ideal Complement to LC-MS

Sample Mixture of known 1:1 ratio

LC-MS results show ratio to be3:1

UV-Vis result show ratio to be10:1

PL-ELS 2100 results show ratio to be1:1

(Response independent of optical properties)

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PL-ELS 2100 Sensitivity - Limit of Detection

Column: C18 5µm,150x4.6mmEluent A: 99% Water + 0.1 % TFAEluent B: 1% ACN + 0.1% TFAFlow Rate: 0.5ml/minDetector: PL-ELS 2100 (neb=50°C, evap=70°C, gas=1.2 L/min)Sample: DL-Glutamic Acid

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PL-ELS 2100 Sensitivity - Limit of Detection

• LOD improved with lower eluent flow rates and smaller ID column

4.6 ID S/N = 4.4

Caffeine Loading 30ng

2.1 ID S/N = 11.5

Caffeine Loading 100ng

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Operating the PL-ELS 2100: Onboard Instrument Control

Keypad

Interactive menu bar

Current methodMode

Detector output

Status

Actual values of set parameters

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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

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• 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)

Digital Signal Processing

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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

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PL-ELS 2100 Control Software

• 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

• 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

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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)

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PL-ELS 2100 Method Manager

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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

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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.

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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

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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

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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

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Environmental Application:Herbicides

Sample: Mixture of 10 Phenylurea herbicides


Eluent A: Water


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)

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Environmental Application: Herbicides

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Non-Volatile Applications: PEG 400 Separation

Sample: PEG 400

Column: PLRP-S 100Å 5µm, 150x4.6mm

Eluent A: Water

Eluent B: ACN


Flow Rate: 1.0mL/min

Inj Vol: 10µl

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PEG 400: Effect of Changing Temperature

Evap 30°C Neb 30°C Gas 1.6 L/min


Higher temperatures increase S/N, no risk of loss due to evaporation

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PEG 400: Effect of Changing Gas Flow



Sensitivity is improved as gas flow is reduced

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Sample: 2mg/ml Starflower Oil


Eluent A: ACN

Eluent B: DCM

Gradient: 30-50% B in 40 mins; 50-90% in 2 mins,

hold for 3mins


Inj Vol: 20µl

Detector: PL-ELS 2100 (neb=40°C, evap=70°C, gas=1.4 L/min)

Non-Volatile Application: Triglycerides in Natural Oils

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Non-Volatile Application: Triglycerides in Natural Oils

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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

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Supercritical Fluid Chromatography PEG Separation

Reduced band broadening allows high resolution SFC separations to be performed

PEG 1000

41

PL-ELS 2100:DMSO Transparency

Sample: Pharmaceutical Mixture in DMSO


Eluent A: Water




Inj Vol: 20µl

Detector: PL-ELS 2100 (neb=25°C, evap & gas flow varied)

42

PL-ELS 2100 DMSO Transparency:Ideal for High Throughput Screening

Loss of volatile species occurs as temperature is increased

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•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

PL-ELS 2100: DMSO Transparency:Ideal for High Throughput Screening

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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

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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

detect everything you inject with the pl-els 2100 evaporative light scattering detector

Documents

uv chromophore

uniform detection sensitivity

stray light loss

controlled plels

els traces

nmcomparison of uv

mobile phasedetects

lmin uvvis