1. 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
200mm
Display
Keypad
415mm
Column Connection
Liquid Waste
450mm
450mm

4. Principle of Operation
The ELSD principle of operation employs three distinct stages :
Nebulization
Evaporation
Detection
Gas
Eluent Inlet
Light Source
Liquid Waste

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

8. 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

9. Advantages of Evaporative Light Scattering Detection: Pharmaceutical Mixture
Detects all components in a single run
Samples : 1. α-cyclodextrin ß-cyclodextrin Ibuprofen
Column: Aquasil C18 5µm, 150x4.6mm
Eluent A: Water
Eluent B: Acetonitrile
Gradient: % 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
220nm

10. 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

11. 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: µl
Detector: PL-ELS 2100 (neb=30°C, evap=30°C,
gas=1.4 L/min)
280nm

12. 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

13. 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

14. Fast Gradient, Fast Flow Rate Capability
2ml/min
3ml/min
4ml/min
5ml/min
IND
DBP
min

15. Fast Gradient, Fast Flow Rate Capability
Stable baseline throughout the gradient
PL-ELS 2100 can operate in 100% up to 5ml/min
2ml/min
3ml/min
4ml/min
5ml/min
min

16. Similar operating principles to LC-MS
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 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

17. Ideal Complement to LC-MS
Sample Mixture of 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)

18. PL-ELS 2100 Sensitivity - Limit of Detection
Column: C18 5µm,150x4.6mm
Eluent A: 99% Water % 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

19. 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

20. Operating the PL-ELS 2100: Onboard Instrument Control
Interactive menu bar
Current method
Mode
Detector
output
Status
Actual values of set parameters
Keypad

21. Two modes of operation :
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
LED on
Temperatures and gas flow controlled to set values

22. 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)

23. PL-ELS 2100 Control Software
Select mode of operation
Control parameters
Evaporator & Nebulizer temp
Gas flow ( L/min)
Monitor output
Gain setting ( )
Signal smoothing (0-5)
Log instrument conditions over time
Load / Edit methods
- 10 programmable methods

24. 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

25. 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
To use this software utility, simply connect the PL-ELS 2100 to a PC via a serial connection (RS232)

26. PL-ELS 2100 Method Manager

27. 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

28. 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.

29. 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

30. 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: %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

31. 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

32. Environmental Application:Herbicides
Sample: Mixture of 10 Phenylurea herbicides
Column: C18 5µm, 250x4.6mm
Eluent A: Water
Eluent B: Acetonitrile
Gradient: %B in 40 mins
Flow Rate: 0.7ml/min
Inj Vol: 20µl
Detector: PL-ELS 2100 (neb=25°C, evap & gas flow varied)

33. Environmental Application: Herbicides

34. Non-Volatile Applications: PEG 400 Separation
Sample: PEG 400
Column: PLRP-S 100Å 5µm, 150x4.6mm
Eluent A: Water
Eluent B: ACN
Gradient: % B in 12 mins
Flow Rate: 1.0mL/min
Inj Vol: 10µl

35. 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

36. 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

37. Non-Volatile Application: Triglycerides in Natural Oils
Sample: 2mg/ml Starflower Oil
Column: C18 5µm, 250x4.6mm
Eluent A: ACN
Eluent B: DCM
Gradient: % 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)

38. Non-Volatile Application: Triglycerides in Natural Oils

39. 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: µl
Detector: PL-ELS 2100 (neb=40°C, evap=30°C, gas=0.9 L/min)

40. 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
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)

42. PL-ELS 2100 DMSO Transparency: Ideal for High Throughput Screening
Loss of volatile species occurs as temperature is increased

43. 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

44. 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

45. 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