The central component of the technology is the ferrule which consists of a metal jacketed cylindrical graphite wafer. This ferrule has a precision hole drilled through it that is matched with the column outside diameter. This provides a low dead volume connection that is also self centering – a feature that is extremely important for single and dual column connection to a GC inlet.

GRAPHPACK 2M connection technology

For the rapid and economical connection of capillary columns to GC Inlets and Detectors.

GRAPHPACK 3D/2 connection technology

For the rapid, reliable and low-dead-volume connection of two capillary columns with the same or different outside diameter, or of different materials.

GERSTEL GRAPHPACK 2M

Simple and cost-effective technology for connecting capillary GC columns to inlets, detectors and Swagelok fittings.

GRAPHPACK-2M enables simple and reliable low-dead-volume connection of columns to inlets, detectors and Swagelok® fittings. The GRAPHPACK-M ferrules use a slotted GRAPHPACK nut for tightening. The components of the GRAPHPACK 2M connection technology are the GRAPHPACK 2M ferrule, the GRAPHPACK 2M adapter and the GRAPHPACK nut.

GERSTEL GRAPHPACK® technology was designed to provide leak-free, low dead volume, inert connections quickly and reliably for any type of connection used for gas chromatography. The same technology is used for inlet and detector connections as well as for column connections (with or without make-up gas) and multiple column splitters. GRAPHPACK fittings exist for almost all GC inlets and detectors, so a laboratory with multiple brands of GCs can use the same ferrules, adapters, and nut for all connections needs.

The central component of the technology is the ferrule which consists of a metal jacketed cylindrical graphite wafer. This ferrule has a precision hole drilled through it that is matched with the column outside diameter. This provides a low dead volume connection that is also self centering – a feature that is extremely important for single and dual column connection to a GC inlet.

There are five main types of GRAPHPACK fittings:

• Column Connectors for all column types and diameters
• Detector Adapters for connecting capillary columns to most GC detectors
• Flow Splitters for splitting column flow between up to three separate streams
• Inlet Adapters for connecting capillary columns to most GC inlets
• Swagelok Adapters for connection standard Swagelok fittings to capillary columns

GERSTEL GRAPHPACK 3D/2

Simple and cost-effective low-dead-volume connection of capillary columns with the same or different diameters.

GRAPHPACK 3D/2 enables simple and reliable low-dead-volume connection of two capillary columns with the same or different diameters. The components of the GRAPHPACK 3D/2 connection technology are the GRAPHPACK 3D/2 ferrule, the GRAPHPACK 3D/2 connector and the GRAPHPACK 3D/2 screw.

GERSTEL GRAPHPACK® technology was designed to provide leak-free, low dead volume, inert connections quickly and reliably for any type of connection used for gas chromatography. The same technology is used for inlet and detector connections as well as for column connections (with or without make-up gas) and multiple column splitters. GRAPHPACK fittings exist for almost all GC inlets and detectors, so a laboratory with multiple brands of GCs can use the same ferrules, adapters, and nut for all connections needs.

The central component of the technology is the ferrule which consists of a metal jacketed cylindrical graphite wafer. This ferrule has a precision hole drilled through it that is matched with the column outside diameter. This provides a low dead volume connection that is also self centering – a feature that is extremely important for single and dual column connection to a GC inlet.

There are five main types of GRAPHPACK fittings:

• Column Connectors for all column types and diameters
• Detector Adapters for connecting capillary columns to most GC detectors
• Flow Splitters for splitting column flow between up to three separate streams
• Inlet Adapters for connecting capillary columns to most GC inlets
• Swagelok Adapters for connection standard Swagelok fittings to capillary columns

This sounds simple enough, but until now it hasn’t been, since techniques that require a second dimension (column) require a lot of additional hardware, including an extra GC. Not anymore: The patented GERSTEL Selectable 1D/2D-GC/MS System enables the best of both worlds. The system can be used for routine single dimensional GC/MS analysis, and with the click of a mouse, can be switched to perform twodimensional separation when needed for more complex matrices. This allows interesting sections of the chromatogram to be collected and concentrated from multiple runs to better separate and isolate trace compounds. This can, for example, be used for trouble shooting when off-odors are detected in a product. All this is performed using just one GC/MS system.

Food analysis is certainly not a trivial matter. The typical matrix is complex, often requiring several sample preparation steps and extensive sample cleanup. However, even well prepared samples can produce forests of overlapping peaks making it a case of not being able to see the trees for the forest. If a case of unresolved peaks is clearly at hand, or if an odor detected by using an Olfactory Detection Port (ODP) doesn’t match the peaks in the chromatogram, the user needs to have a good tool kit at her or his disposal. In this case, selectable multidimensional GC can be the technique that cuts through the thicket and provides clear, reliable answers whenever one-dimensional GC does not.

An attractive alternative to standard systems

Until now, multi-dimensional GC required the use of a dedicated system with two GCs coupled to each other. Due to the extra cost, and to the often limited utilization in the laboratory, such solutions didn’t always provide the best return on investment (ROI). GERSTEL now offers a solution that can be used for routine analysis as well as for special challenges. The patented GERSTEL Selectable 1D/2D-GC/MS is a flexible system, based on a single standard GC/MS instrument. It is both a routine analysis system and a complex problem solving system that offers heartcutting and two-dimensional separation on demand. Because of this dual functionality, when questions arise regarding a section of the standard one-dimensional chromatogram, this section in question can be transferred to a 2nd dimension, i.e. a GC column with different polarity to further increase separation.

Both columns are installed in the same GC and are heated independently using Low Thermal Mass (LTM) technology. The process of cutting a section of a chromatogram and introducing it to another column is called heart-cutting. The 1D/2D system can be used to determine analytes in either the 1st or the 2nd dimension in a flexible manner. Neither the GC run, nor analyte detection is interrupted during the run. Detection of the analytes that were transferred to the 2nd column follows using the same detector(s) used for the 1st dimension: MSD, Olfactory Detection Port (ODP), PFPD etc. etc.

Should lower detection limits be required for the analyte in question, the system enables heart-cutting from multiple repeat injection, with cryofocusing of the sections that were cut, on a GERSTEL Cryo Trap System (CTS). The accumulated sections are then transferred to the 2nd dimension once there is sufficient mass on column to perform the determination.

Wide Range of Applicability

Until now, Selectable 1D/2D-GC/MS systems have mainly been sold to, and used for food, flavor, and fragrance analysis, but any application that occasionally requires a 2nd dimension separation to solve a puzzle would benefit from having such a system available at a reasonable cost. Further, detection of analytes in both dimensions is performed using one or more detectors simultaneously including MSD, ODP, FID or PFPD. The complete system is efficiently and conveniently controlled by mouse-click through the GERSTEL MAESTRO software, integrated with the Agilent ChemStation. It couldn’t be simpler.

Two CTS models are available:

• CTS 2 for mounting inside the GC oven
• CTS 1 for mounting between two GCs in multi-oven multidimensional systems

The CTS can be upgraded to a Cryogenic Trap Enrichment System CTE. The CTE includes an electronic proportional valve between the columns compensates for flow differences enabling separation under optimal conditions on both the pre-column and the analytical column.

When trapping has been completed, analytes are released from the trap using a highly accurate temperature program. Analytes are introduced in a sharp band at the head of the GC column ensuring better detection limits and better resolution. For even lower detection limits, analytes from multiple injections can be concentrated onto the CTS.

Cryogenic Trap Systems offer:

• Introduction of compounds as a narrow band onto the analytical column
• Sharper peaks for better resolution and lower detection limits
• Compatible with all GERSTEL column switching systems e.g. MCS
• Intuitive MAESTRO software control
• Integrated method and sequence table for complete system including GC/MS

All aspects of system operation are controlled through GERSTEL Maestro software, no complicated pressure balancing or cut table definitions are required. No other system can analyze complex samples this easily.

Features

• Independent flow control of pre-column and analytical column
• Integrated Cold Trap System
• Pressure- and flow programming using EPC pneumatic systems
• Easily installed in new or existing GC systems
• Convenient MAESTRO software control

Applications

• On-line clean up using a combination of columns with different inside diameter and film thickness.
• Optimum GC separation, even when combining capillary columns of widely differing diameter, flow and length.
• All Dual Column Switching DCS applications.