An Agilent Guide to SPME Analysis
An Agilent Guide to
SPME Analysis
Jessica Westland
Sample Preparation Application Scientist
March 26, 2020
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An Agilent Guide to SPME Analysis; DE.222337963
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Agilent offers high-quality products for SPME sample preparation
An Agilent Guide to SPME Analysis; DE.222337963
Solid Phase Microextraction (SPME) is a fast, solvent-less sample extraction
technique.
It is used for extracting organics from a matrix (solid, liquid, or gaseous) into
or onto a stationary phase immobilized on a fiber.
In SPME, analytes establish equilibria among the sample matrix, the
headspace above the sample, and a polymer-coated fused fiber.
Two types of extraction:
• Headspace (most common)
• Direct immersion (application specific) – SPME fiber is immersed into the aqueous
sample
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Sample preparation technique
What is Solid Phase Microextraction (SPME)
Headspace
Immersion
An Agilent Guide to SPME Analysis; DE.222337963
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SPME characteristics
Parts of the SPME Fiber/Arrow
An Agilent Guide to SPME Analysis; DE.222337963
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SPME fiber hub colors
Key Component
– The Phase
85 μm Polyacrylate
Grey
30 μm PDMS
Gold
100 μm PDMS
Red
7 μm PDMS
Green
95/10
μm CAR-WR/PDMS
Dark Blue
65
μm DVB/PDMS
Violet
80/10
μm DVB/CAR-WR/PDMS
Dark Grey
Acronym
Full Name
PDMS
Polydimethylsiloxane
PA
Polyacrylate (aka acrylate)
DVB
Divinylbenzene
C-WR
Carbon Wide Range
An Agilent Guide to SPME Analysis; DE.222337963
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SPME Arrow hub colors
Key Component
– The Phase
100
μm Polyacrylate
Grey
120
μm CAR WR/PDMS
Light Blue
100 μm PDMS
Red
120
μm DVB/CAR WR/PDMS
Dark Grey
250
μm PDMS
Black
120
μm DVB/PDMS
Violet
Acronym
Full Name
PDMS
Polydimethylsiloxane
PA
Polyacrylate (aka acrylate)
DVB
Divinylbenzene
C-WR
Carbon Wide Range
An Agilent Guide to SPME Analysis; DE.222337963
SPME Functionality
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An Agilent Guide to SPME Analysis; DE.222337963
Fibers/Arrows MUST be preconditioned prior to first use (or after sitting)
• Done at a specified temperature in an inert gas phase environment (He or N2)
Fibers/Arrows MUST be conditioned prior to and/or after desorption of sample
– cleans the fiber
• Done at a hotter temperature than the injection/inlet temperature
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SPME functionality
Fiber/Arrow Conditioning
An Agilent Guide to SPME Analysis; DE.222337963
The Agilent manual injection kit (p/n 5191-5877) will allow the end user to extract samples
using SPME fibers or arrows and then inject the samples into a GC inlet.
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SPME functionality
SPME Manual Sampling
Part
Component
1
Extraction guide
2
Injection guide
3
Arrow/fiber syringe
4
Large inner diameter (id) locking screw
5
Small inner diameter (id) locking screw
Alignment ring (p/n G7371-67001)
*Not included in kit
An Agilent Guide to SPME Analysis; DE.222337963
Manual SPME sampling: SPME fibers and Arrows
A detailed step-by-step guide (with images) to assist with the
installation of a SPME fiber or Arrow into the manual sampling holder
for either headspace or immersion sampling and adjustments for the
injector penetration depth.
An Agilent Guide to SPME Analysis; DE.222337963
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Agilent demonstration guide: 5994-1732EN
SPME Manual Sampling
Agilent’s SPME fibers and Arrows work directly with your current rail system.
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SPME functionality
SPME Automated Sampling
PAL SPME Arrow tool
PAL3 Series RSI and
PAL RTC
PAL SPME fiber tool
PAL3 Series RSI and
PAL RTC
PAL-xt Holder
For PAL and PAL-xt systems
with CombiPAL and PAL
Combi-xt - Fibers Only
PAL SPME tool
For older PAL system
Models (or corresponding
OEM rails). Fibers only.
An Agilent Guide to SPME Analysis; DE.222337963
Due to their larger diameter, SPME Arrows require instrumental changes in addition to
obtaining the SPME Arrow option on the PAL3 rail system
.
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You need an enlarged GC turn top assembly
You must use an inlet liner with a larger diameter
SPME Automated Sampling
Changes for SPME Arrows
GC Model
Agilent Part No.
7890B GC
G3452-60930
8890/8860 GC
G3450-60638
Intuvo 9000
G4585-60633
Inner
Diameter
Requirement
Agilent
Part No.
0.75 mm
SPME fibers only
5190-4048
2 mm
Both SPME fibers
and Arrows
5190-6168
0.75 mm id
2 mm id
An Agilent Guide to SPME Analysis; DE.222337963
SPME Applications
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An Agilent Guide to SPME Analysis; DE.222337963
Equilibrium condition
• Sorbent material
• Temperature
• Time
Kinetics influence
• Stirring/agitation
• Salting out
• pH Value
• Temperature
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Applications
SPME Sampling
Supelco 2011 - Michel, F., Buckendahl, K., Basics in Solid Phase Micro Extraction (SPME), EuroAnalysis presentation
Extraction Time
Intensity
Time control critical for
quantitation, needs auto-sampling
An Agilent Guide to SPME Analysis; DE.222337963
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Applications
SPME Sampling
– Salting out
Arrow 120
μm CAR WR/PDMS
Black trace
– with NaCl at 3 ppb
Blue trace
– without NaCl at 3 ppb
An Agilent Guide to SPME Analysis; DE.222337963
Speed
• Shorter extraction speed
• For same response as fibers
– Improved productivity
– Higher sample throughput
Sensitivity
• Higher response
• At same extraction time as fibers
– Lower detection limits
– Improved precision
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Applications
SPME Fiber or Arrow
Extraction Time
Intensity
SPME Arrow
SPME fiber
An Agilent Guide to SPME Analysis; DE.222337963
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Applications
SPME Fiber or Arrow
5 ppb BTEX with 5 min incubation and 3 min
extraction
Black trace
– Arrow
Blue trace
– fiber
An Agilent Guide to SPME Analysis; DE.222337963
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Applications
Analyte Relation to Phase Type
Thinner coatings
For higher MW compounds
Can accept higher conditioning temperature
Thicker coatings
Require longer extraction times
Use lower conditioning temperature
Absorbent
Adsorbent
85 μm Polyacrylate
30 μm PDMS
100 μm PDMS
7 μm PDMS
65
μm DVB/PDMS
95/10
μm CAR-WR/PDMS
80/10
μm DVB/CAR-WR/PDMS
An Agilent Guide to SPME Analysis; DE.222337963
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Applications
Analyte Relation to Phase Type
85 μm Polyacrylate
30 μm PDMS
100 μm PDMS
7 μm PDMS
65
μm DVB/PDMS
Nonpolar
Bipolar
Nonpolar high MW compounds
Nonpolar semi-volatiles
Volatiles
Polar semi-volatiles
Gases and volatiles
Polar volatiles
Odors and flavors
Polar
95/10
μm CAR-WR/PDMS
80/10
μm DVB/CAR-WR/PDMS
An Agilent Guide to SPME Analysis; DE.222337963
Polycyclic aromatic hydrocarbons (PAHs) are a large class of organic compounds containing
two or more fused aromatic rings. PAHs are considered compounds of concern by every
environmental organization; their concentration in water is strictly regulated.
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Learn more, search 5994-1301EN at www.agilent.com
Examination of Lower Molecular Weight PAHs in Drinking Water Using Agilent
PDMS SPME Fibers
SIM chromatogram of naphthalenes with PDMS fibers
(black trace = 100 µm; green trace = 30 µm; blue trace = 7 µm)
SIM chromatogram of fluoranthene and pyrene with PDMS fibers
(black trace = 100 µm; green trace = 30 µm; blue trace = 7 µm)
Naphthalene
1-Methylnaphthalene
2-Methylnaphthalene
Fluoranthene
Pyrene
An Agilent Guide to SPME Analysis; DE.222337963
Toluene (R2 = 0.9990)
Linear; Origin: Ignore; Weight: None.
The production of safe drinking water is an important issue, and legislation has established
allowed levels of chemical substances in drinking water, whether they occur naturally, as
deliberate additions, or as contaminants.
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Learn more, search 5994-1104EN at www.agilent.com
Analysis of BTEX in Water with a CAR-
WR/PDMS 95 μm SPME Fiber
MTBE
Benzene
Toluene
Ethylbenzene
m/p-Xylene
o-Xylene
Toluene linear calibration curve
1.25 ppb on column (Replicate #3; CAR-WR/PDMS 95 µm SPME Fiber)
An Agilent Guide to SPME Analysis; DE.222337963
The addition of NaCl increased the extraction efficiency for the analytes of interest.
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Learn more, search 5994-1045EN at www.agilent.com
Determination of VOCs in Water by GC/MS after Headspace-Solid-Phase
Microextraction (HS-SPME)
Chromatogram of 0.8 ppb BTEX standard analyzed by a 120 μm CAR WR/PDMS; SPME Arrow with NaCl (red trace) and without NaCl (black trace)
An Agilent Guide to SPME Analysis; DE.222337963
Since terpenes have high vapor pressures, and are extremely volatile, they are excellent candidates for static
headspace (HS) gas chromatography/mass spectrometry (GC/MS) analysis.
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Learn more, search 5994-1411EN at www.agilent.com
SPME-GC/MS of Selected Terpenes using Agilent DVB/CAR-WR/PDMS
SPME Fiber
Selected terpenes in cannabis flower sample 3648: (-)-Isopulegol, Terpineol, b-Caryophyllene, and (+)-Cedrol
Agilent products and solutions are intended to be used for cannabis quality control and safety testing in laboratories where such use is permitted under state/country law.
An Agilent Guide to SPME Analysis; DE.222337963
PAL SPME Arrows provided the sensitivity and robustness needed to profile the predominant terpenes in an
unknown variety of cannabis plant samples
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Learn more, search 5994-1046EN at www.agilent.com
SPME Arrow Sampling of Terpenes in Cannabis Plant Material
Flower samples profiled with the use of the 120 μm DVB/CAR WR/PDMS (p/n 5191-5861) Arrow
Flower sample 1367
Flower sample 3648
Flower sample 3812
Flower sample 3813
An Agilent Guide to SPME Analysis; DE.222337963
Agilent products and solutions are intended to be used for cannabis quality control and safety testing in laboratories where such use is permitted under state/country law.
Organophosphorus insecticides are among the most widely used pesticides throughout the
world. As a result of their widespread use their residues have been detected in samples such
as surface waters, soil, and agricultural products.
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Learn more, search 5994-1546EN at www.agilent.com
Analysis of Parathion-Ethyl in Water with an
85 μm Polyacrylate SPME Fiber
Integrated Chromatogram of Parathion (ethyl) in water
An Agilent Guide to SPME Analysis; DE.222337963
• Immersion sampling sensitivity is improved by filling the sampling vial to a
minimum of 80%
• Immersion sampling works best for low concentration water-based sample
matrices
• When using immersion for samples containing sugars, proteins, and
particulate matter, rinse the fiber in water before desorption.
• This will extend fiber life and reduce injection port contamination.
• Position the fiber just below the sample surface for immersion sampling and
maintain this position consistently for all extractions.
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Best practices
Immersion Sampling
Immersion
An Agilent Guide to SPME Analysis; DE.222337963
The main compound responsible for cork taint is 2,4,6-trichloroanisole. It is one of the most
odor intense compounds known and has a distinct musty, moldy aroma.
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Learn more, search 5994-1564EN at www.agilent.com
SPME-GC/MS of 2,4,6-trichloroanisole Using Agilent DVB/PDMS SPME Fiber
2,4-Dichloroanisole and 2,4,6-Trichloroanisole @ 25 ppb in Red Wine
An Agilent Guide to SPME Analysis; DE.222337963
SPME Troubleshooting
Make troubleshooting faster and easier by closely observing and keeping
complete records of your analytical methodologies
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An Agilent Guide to SPME Analysis; DE.222337963
Improper alignment is one of the main causes of fiber/arrow damage.
•
Follow Agilent’s Demonstration Guide (5994-1732EN) to ensure proper alignment and set up of
the manual sample holder
•
Retract fiber into protective needle during insertion into vial/injection port and removal
•
Check for proper alignment of the PAL3 fiber/arrow needle with the injector, vial trays, and vials
•
Make sure that the insertion depths into the vials and injection port are properly set
•
Use larger splitless inlet liners without glass wool or adsorbents
–
p/n 5190-4056 (5/pk): splitless, straight, 0.75 mm id
–
p/n 5190-4047 (1/pk): splitless, straight, 1 mm id
–
p/n 5190-6168 (1/pk): splitless, straight, 2 mm id (use for SPME Arrows)
•
Avoid stress of the needle by keeping agitation speed low
–
Agitator module: < 600 rpm
–
Heatex Stirrer module: < 1300 rpm
Note: All Agilent SPME fiber assemblies use 23 gauge
needles for increased strength and less bending
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SPME troubleshooting
Needle Bends/Fiber Breaks
An Agilent Guide to SPME Analysis; DE.222337963
Septum of sample vial cap is too thick
• Use on Agilent screw headspace magnetic caps (p/n 5188-2759; 18 mm) PTFE/silicone septa (top
white, bottom blue) on Agilent amber screw top headspace sampling vials (p/n 5188-6537; 20 mL)
Septum in injection port is too thick or too tight
• Loosen the nut slightly to allow for improved injection
Septum coring
• Use a septum-less injector system (i.e. Merlin Microseal)
– Fibers:
• p/n 5182-3445: Merlin Microseal 100 psi nut
• p/n 5182-3444: Merlin Microseal general-purpose replacement Microseal
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SPME troubleshooting
Septum Issues
An Agilent Guide to SPME Analysis; DE.222337963
Coatings will discolor when heated too high or there are leaks in the flow path
• Minimize oxygen in carrier gas, condition fibers in oxygen free gas flow
– p/n CP17970: Gas Clean oxygen purifier
– p/n CP17973: Gas Clean carrier gas purifier
• Reduce the injection port temperature to the recommended maximum setting
• Carbowax/DVB may slightly darken during use
– Sensitive to temperature (< 260
°C is recommended)
• The polyacrylate coated fiber will discolor above 280
°C
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SPME troubleshooting
Discolored Coatings
An Agilent Guide to SPME Analysis; DE.222337963
Endogenous peaks in chromatogram
•
Precondition fiber/arrow prior to sampling
•
Use low-bleed septa to minimize injection port septum bleed or a septum-less injector system (i.e. Merlin
Microseal)
•
Replace the inlet liner
Interfering peaks
•
Change GC column or temperature program rate
Carryover from previous analysis of the fiber
•
Bake out fiber/Arrow at the recommended conditions for several more minutes
Poor reproducibility
•
Time of extraction and temperature are the two most critical conditions to control
•
Make sure the positioning of the fiber/arrow is consistent from sample to sample
•
Apply uniformly across all extractions with any pH or salt adjustments
•
Use internal standards, surrogates, or the standard addition technique to compensate for variations in
sample matrix
•
Maintain the same headspace volume and agitation conditions across all extractions
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SPME troubleshooting
Data Analysis
An Agilent Guide to SPME Analysis; DE.222337963
Agilent offers high-quality products for SPME sample preparation
Agilent puts together the supplies for both manual and automated SPME sampling
Agilent follows the market trends to keep you up to date with application notes and technical
collateral
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Solid phase microextraction (SPME)
SPME Summary
An Agilent Guide to SPME Analysis; DE.222337963
Columns, Sample Prep and Supplies Questions
Do you have questions about the following during a potential lab shutdown?
• Column storage
• What to do with mobile phase, buffers, and other HPLC solvents
• Chemical standards storage
• What supplies to stock up on to get your instrument back up and running in a timely manner
Take advantage of Agilent’s best-in-class columns, sample prep, and supplies technical
support!
An Agilent Guide to SPME Analysis; DE.222337963
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Contact Agilent Chemistries and Supplies Technical Support
1-800-227-9770 Option 3, Option 3:
Option 1 for GC/GCMS Columns and Supplies
Option 2 for LC/LCMS Columns and Supplies
Option 3 for Sample Preparation, Filtration and QuEChERS
Option 4 for Spectroscopy Supplies
Option 5 for Chemical Standards
800 Phone lines available 8-5 in all US time zones
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Looking to increase your knowledge during your lab shutdown?
Check out on-demand and live webinars on GC/GCMS, LC/LCMS and Sample Prep consumables.
https://www.agilent.com/en/training-events/eseminars/gc-gc-ms-webinars
https://www.agilent.com/en/training-events/eseminars/lc-lc-ms-column-e-seminars
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An Agilent Guide to SPME Analysis; DE.222337963
Thank You
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An Agilent Guide to SPME Analysis; DE.222337963
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