Expanding Capabilities of the MPS for

GC/MS Applications: Packaging

Malodors and Food Flavors

Kurt ThaxtonGERSTEL

Intro to GERSTEL automated sample preparation

technology for GC/MS

Applications for Flavor and Fragrance Analyses:

Stir Bar Sorptive Extraction (SBSE) of Benzophenone in Paperboard

Full aroma and flavor profiling of Beer samples

Fraction Collection, Re-visited

Outline

CTC

PAL

HS

Liq

SP

ME

What Can you do with

a CombiPAL?

TD

Dual

Head

Pyro

MPS GC

ATEX Thermal

Extraction in µVials

TDU Thermal Desorption

•and PYROlysis

Dynamic

Headspace

DHS

Solid Phase

Extraction SPE

Dispersive Pipette

Extraction DPX

SPME & Multi-

Fiber EXchange

MFX

ALEX Automated

Liner EXchangeHeadspace

MPS GC

TDU Thermal Desorption

•and PYROlysis

Cooled Injection System - CIS

Thermal Desorption Unit - TDU

TDU Tube

TDU

No Transfer line !

Universal Thermal Desorption Unit

TDU

TDU liner with frit for thermal

extraction of solid samples

TDU liner packed with adsorbent

TDU liner for Twister desorption

TDU liner for thermal extraction in µ-vials

Analysis of Malodors

(Baltimore NCIS*)

*Nasty Chemicals Insulting the Senses

• PDMS coated magnetic stir bar

PDMS or PDMS/PEG

coating

Magnetic core

Glass mantle

Twister (SBSE) Sample Preparation

Add GERSTEL Twister to vial

Stir for 1 hour

Rinse in distilled water

Dry with tissue

Analyze in TDU

Up to 1000 times more sensitive

than SPME

Widely used with food simulants

Applications:- http://www.gerstel.com/en/apps-twister-

sbse.htm

Time for the Big Guns

Approach: Identifying odor compounds

- Choosing the sampling technique

How do you know you have trapped the target

compound? Aim for non-selectivity

- Put enough mass on column

- Couple MS with olfactometry

- Manage complex sample matrix with GC-GC

Standard modes

- Liquid, HS, SPME

Thermal extraction

- Solids

- Liquids (ATEX)

Thermal Desorption

- Adsorbent tubes

- SBSE (Twister)

Dynamic Headspace

Choose an introduction

mode that is compatible

with the sample and

provides enough mass

on column to detect the

target analyte.

Ideally NON-

SELECTIVE

Two Approaches to Multidimensional GC

Heartcutting GC-GC- Standard (30m) precolumn

- Standard (30m) second column

- Selected portions of the first chromatogram “cut” to second

dimension

- Compatible with splitting to several detectors- FPD, ODP

Comprehensive GCxGC- Standard (30m) precolumn

- Very short (1m) second column

- All compounds from precolumn are sent to second column

- Usually requires fast data acquisition (TOF)

Olfactory

Detection

Port

GC-Olfactometry

Split column

effluent between

MS and ODP

Voice recognition

software to

capture analyst

descriptors

Non-dedicated system

- can be used for both 1DGC-MS and 2DGC-MS without

• any instrumental set-up change

The selection of 1D or 2DGC-MS is only performed

by a “Change of the method” (click of the mouse).

No preliminary injection before heart-cutting

- 2DGC-MS can be performed just after 1DGC-MS run2DGC-MS can be performed just after 1DGC-MS run

Selectable 1D or 2DGC-MS

We developed a Selectable 1D or 2DGC-MS with

selective detection using CFT and dual LTM-GC

•CFT

+ +

“Monitor TIC” can be obtained as the 1st dimension for 2DGC-MS

Heart-cutting

1D TIC (DB-Wax)

SBSE – GC – O/MS:

Beer Sample: 10 mL, Twister: 1 cm x 500 µm, SBSE: 120 min, Injection: Splitless

1st Column: DB-Wax, 2nd Column: DB-5, Sniffing device: GERSTEL ODP2,

GC-MS: Agilent 7890GC/5975MSD, ODP/MS Split ratio: 1/1

SBSE-TD-1DGC-O/MS: Beer

Sweet & Honey

Phenethyl acetate + ??

“Change of the method

by click of the mouse”

•SBSE – GC – GC – O/MS:

•Beer Sample: 10 mL, Twister: 1 cm x 500

•

SBSE-TD-2DGC-O/MS: Heart-cutting & Back Flush

Back Flush

１DGC-MS

2DGC-MS

w/Back Flush

Heart-cutting

2D TIC (DB-5)

Both the 1D TIC and the 2D TIC could be obtained on the

same chromatogram in a single run.

1D TIC (DB-Wax)

•SBSE – GC – GC – O/MS:

•Beer Sample: 10 mL, Twister: 1 cm x 500

•

SBSE-TD-2DGC-O/MS: Beer

GC-O Signal

Back Flush

Heart-cutting 2D TIC (DB-5)1D TIC (DB-Wax)

Phenethyl acetate

?

2D TIC (DB-5)

SBSE-TD-2DGC-O/MS: Beer

?

•GC-O SignalMass Spectrum

NIST Library Search Result: β-Damascenone

β-Damascenone

β-Damascenone is known as kind of rose ketone. The odor description is “Sweet, Fruity,

Plum, Raspberry, etc.”, and the odor threshold in water is quite low, with values in the

literature in the range of 20 to 90 ng/L 7).

Fraction Collection:Sometimes You Really Do Want to Repeat Yourself

Preparative

Fraction

Collector

PFC•Transfer line from GC

•Waste trap in cooled

compartment

•Fraction traps•Fraction traps

•Preparative

Switching

•Device

•Cooled trap compartment •Cooled trap compartment

Setup for ODP 3

Replace ODP cone with Tenax TA

“Simple Fraction Collection”Selectable 0:1, 1:0, or 1:1 w MSD

Advantages of Post-Column Collection

ODP Port!

Independent of Sample Introduction Technique

“Selective” Fraction Collection

- Can Collect “Splitless” Injections at 50%

- Solvent not Collected

- Tail-end Junk not Collected (or Middle Stuff too!)

For Split, Little “Cost” Compared to Pre-Column- Based on 1:10 Splitting, only about 1.8x Less but no solvent or junk

Manual or Automated- Simple, Easy to Manually Time Recollection

- Alternately Can Be Automatic, Software-Selectable

- Can Automatically Recollect Several Fractions or Samples with PFC

Let’s Build

Something

Cool Together!

(and let

Maestro &

Mass Hunter

run it…)

Diesel Range Organic (DRO) Mix

50 ppm in MeOH

100% to 5975 MSD

Kovats Index Hydrocarbons

Kovats Index Hydrocarbons

50 ppm in MeOH

100% to 5975 MSD…

…Sometimes

Re-Use those Fractions for the

ULTIMATE FFF ANALYZER

N. Ochiai et. al. “Multidimensional gas chromatography

in combination with accurate mass, tandem mass

spectrometry, and element-specific detection for

identification of sulfur compounds in tobacco smoke”

J. Chromatography A 1358(2014) 240-251

DHS-Large Autosampler

Coming

Soon!

SummaryGERSTEL Enhancements and Improvements for

Food-Flavor-Fragrance Analysis

Do Better than L-L Extraction: Use Twister on Packaging Simulants

Sophisticated GC-GC Tools for Malodor Analyses are Easy to Use with Maestro as your Platform

Old Dogs have Cool Tricks: Fraction Collection is the Best Way to Re-Analzye and/or Aggregate Samples