Concentration is performed at user defined temperature, agitation and vacuum levels enabling highly flexible operation with mild temperature conditions and limited analyte loss. Concentration in the mVAP can be combined with a wide variety of sample preparation and clean-up techniques such as SPE, dispersive SPE (DPX), liquid/liquid extraction or filtration with the significant benefit of automated injection of the concentrated sample into a GC/MS or LC/MS system. Every step is controlled by mouse-click using the MAESTRO PrepBuilder. Just one method and one sequence table is needed for the entire process including GC/MS or LC/MS analysis.

mVAP Features and Benefits:

• Efficient concentration of extracts and solutions under controlled conditions
• Improved limits of detection
• Solvent exchange for GC/MS or LC/MS analysis

Concentration in combination with all sample preparation techniques

• SPE and dispersive SPE (DPX)
• Liquid-liquid extraction and membrane extraction (MASE)
• Centrifugation and Filtration

Maximum efficiency

• Concentration directly from elution/sample vials
• No need for cumbersome manual liquid transfer
• Automated loading of 2 mL, 4 mL and 10 mL vials into mVAP
• Parallel evaporative concentration of up to six samples
• Controlled evaporation through user defined temperature, vacuum and agitation levels
• Efficient PrepAhead overlapping of sample preparation and analysis
• Optimal utilization of the complete analysis system, best possible ROI

Intuitive control by mouse-click using MAESTRO Software

• Integrated control of complete process including all sample preparation steps and GC/MS or LC/MS analysis
• Only one sequence table required
• MAESTRO integration provides single method control
• Interfaces with major chromatography vendors’ software packages

Easily replaceable rotors for 2 mL, 4 mL, 10 mL, or 20 mL vials are available. In combination with centrifugation, the GERSTEL MPS performs sample preparation and sample introduction. The MAESTRO PrepAhead functionality ensures Just-In-Time sample preparation followed directly by sample introduction to the LC/MS or GC/MS for best possible productivity and throughput.

Enhanced Sample Preparation Possibilities

• Reliable and quick phase separation for liquid/liquid extraction (LLE)
• Accelerated sedimentation of particles and solids

High flexibility due to quick and easy rotor exchange

• 6 position rotor for 2 mL vials
• 6 position rotor for 4 mL or 10 mL vials
• 2 position rotor for 20 mL vials (force limited to 1500 g)

The GERSTEL MultiPurpose Sampler (MPS) cleans up to 196 samples in a single automated sequence using a wide range of standard syringe filters. Filtration is performed in a simple and highly efficient manner as integral part of the automated sample preparation, for example combined with sample preparation steps such as dilution, derivatization, addition of standards and of course introduction of the cleaned and prepared sample to the LC/MS- or GC/MS system.

MAESTRO software operates all GERSTEL modules and system solutions in a simple, intuitive and efficient manner. All steps in the sample preparation method are set up by mouse-click. Sample preparation and analysis are performed in parallel thanks to the MAESTRO PrepAhead function for best possible productivity and system utilization.

Benefits of the MPS Filter Option

• Filtration performed as part of the overall automated sample preparation process
• Time saving through elimination of tedious and error-prone manual steps
• Laboratory staff is less exposed to potentially toxic solvents, improved work environment
• Rugged operation, reliable and reproducible results, identical treatment of all samples
• High sample throughput and best possible utilization of the analysis system through PrepAhead productivity: Filtration is performed during the ongoing analysis of the preceding sample

All common syringe filter types can be used

• Best possible results: For every application, the right filter type can be used
• Manual methods can be transferred directly and automated

Flexible operation, easily adapting to changing requirement

• One or more 98-position trays for 4 mm syringe filters can be mounted onto the MPS, enabling high throughput operation overnight and during the weekend – even when analysis runs are short
• The 12-position MPS Filtration Tray enables automated filtration using different size syringe filters for maximum flexibility since any suitable standard syringe filter type can be used
• Filtration can be performed using open or sealed vials as per the user requirements

Filtration and GC/MS sample introduction

• Reliable results without risk of injection needle blockage
• Longer life expectancy of inlet liner and GC column since particulate matter is not introduced into the analysis system
• Cost savings through a reduction in maintenance work and improved system up-time

Filtration and LC/MS sample introduction

• Reliable results through protection of the LC column
• Cost savings due to longer column life expectancy, a reduction in maintenance work and improved system up-time
• Optimized system utilization using fast filtration to prepare the next sample during the ongoing LC/MS analysis

GERSTEL DHSLarge Autosampler

The DHSLarge Autosampler enables unattended analysis of up to 11 samples in containers of up to 1L in volume. Series of samples can be analyzed using the PrepAhead function: Sample conditioning and analyte extraction are performed in parallel with GC/MS analysis for best possible productivity and system utilization. Automated screening with the DHSLarge can eliminate tedious, time consuming, and expensive chamber work. Other application areas are determination of volatiles in bulky consumer products or packaging, from which small representative samples cannot easily be taken.

Adsorbent tubes used are stnadard GERSTEL Thermal Desorption Unit (TDU) tubes when using the standard DHS option or 3.5″ tubes when using DHS 3.5+ combined with the GERSTEL TD 3.5+ thermal desorber. Following analyte concentration, the tube is automatically transferred to the TDU or TD 3.5+ for Thermal Desorption and analyte transfer to the GC. Tubes are fitted with individual adapters enabling both automated movement and leak-free sealing during the Dynamic Headspace and Thermal Desorption steps and during storage in the autosampler tray.

Automated Dynamic Headspace combined with sample introduction to a GC or GC/MS system is performed by the MPS and TDU or TD 3.5+. More than 120 samples can be processed automatically in one sequence.

Dynamic Headspace Benefits:

• The GERSTEL Dynamic Headspace provides lower detection limits than static headspace, SPME and other widely used techniques
• High productivity through high throughput design and complete automation from sample preparation to GC/MS analysis
• Highest flexibility: User defined extraction time, flow, temperature and adsorbent
• The Dynamic Headspace technology provides multiple water management options to ensure best chromatography and MS stability

DHS – Powered By MAESTRO, DHS is easily and conveniently controlled from the GERSTEL MAESTRO Software.

Parallel processing of samples enable the DHS process to be performed during the chromatographic run of the preceding sample for optimal productivity and for highest system utilization.

Automated liquid handling in the MPS can be used for additional sample prep steps. As part of the sample prep procedure, standard addition can be performed automatically for best possible analytical results.

Sample prep steps are selected by mouse-click from a pull-down menu using the PrepBuilder function of the GERSTEL MAESTRO software.

A graphical scheduler display for the DHS process provides an overview of the time required for each individual step and for the complete sequence of samples for easier planning.

Just one method and one sequence table controls the complete process from DHS through sample prep and sample introduction to GC/MS analysis. Integrated control ensures a more efficient operation with less risk of error. The GERSTEL MAESTRO Software operates stand-alone or fully integrated with the Agilent Technologies ChemStation Software.

The DHS station provides sample thermostating and agitation combine with purging of the sample headspace with a controlled flow of inert gas. Extracted compounds are trapped and concentrated on a replaceable adsorbent-filled trap, which is subsequently thermally desorbed in the integrated Thermal Desorption Unit (TDU) followed by determination of the analytes using GC/MS. While in the GERSTEL MPS autosampler, samples are stored in standard headspace vials at ambient temperature. Optionally, samples can be stored at controlled temperatures between 4oC to 200oC.

During extraction, samples can be agitated to enhance and speed up the extraction process. The temperature of the adsorbent tube during the DHS process can be independently controlled from 20oC to 70oC for optimal trapping of the analytes of interest. The adsorbent tube can be dry purged for water removal to ensure the best possible chromatography and MS stability. A new adsorbent tube can be used for every sample, eliminating the risk of cross contamination or the same tube can be used for multiple samples as in standard Purge and Trap instruments.

The Disposable Pipette Extraction (DPX) technique was developed by Professor William E. Brewer, Ph. D. from the University of Southern Carolina. Professor Brewer is the Owner-President of DPX Labs. The DPX technique has been automated by GERSTEL using the MultiPurpose Sampler (MPS).

Automated Disposable Pipette Extraction (DPX) offers:

• Fast Extraction: Equilibration and elution occur in seconds
• Low detection limits: Less than 250 µL liquid sample like blood or urine required to reach very low detection limits when combined with large volume injection
• Excellent reproducibility and accuracy
• Complete automation including added sample preparation steps and GC/MS or LC/MS analysis

DPX for LC (LC/MS) and GC (GC/MS). DPX coupled to your chromatographic system.

DPX methods are readily automated using the GERSTEL MPS, which can introduce the extract into a GC/MS or LC/MS system. Additional sample preparation steps can be performed, including derivatization or adding an internal standard. The analyst only needs to place the samples in the MPS autosampler and activate the sequence table from the MAESTRO software. Everything else is performed automatically including GC/MS and LC/MS analysis.

Automated DPX solution for GC and GC/MS

• For coupling DPX to a GC (GC/MS) system the DualRail variant of the MultiPurpose Sampler is needed, thus enabling to use two diferent syringes, one for the DPX process, another one for GC (GC/MS) introduction. Lowest detection limits and highest throughput can be obtained when using large volume injection with the GERSTEL Cooled Injection System (CIS). In this case no additional concentration step is needed.

Automated DPX solution for LC and LC/MS

• For coupling DPX to an LC (LC/MS) system a two tower variant of the MultiPurpose Sampler (MPS) is used enabling to use one syringe for the DPX process and one for LC (LC/MS) introduction.

GERSTEL MAESTRO PrepAhead provides automated overlapping of sample preparation and analysis for highest throughput and system utilization.

The GERSTEL MultiPurpose Sampler (MPS) with Automated SPE Option for standard cartridges provides several benefits compared with manual Solid Phase Extraction:

• Improved recovery, precision and reproducibility
• Maximized sample throughput by performing SPE during GC or LC analysis of the preceding sample
• More than 50 percent time saving for overall analysis, compared to manual processing

Following the SPE clean-up steps, the MPS can introduce the sample extract directly to an LC/MS or GC/MS system for analysis. As an alternative, the MPS WorkStation is used as stand-alone sample preparation robot, preparing samples for multiple LC/MS or GC/MS systems in your laboratory.

The GERSTEL SPE enables automated sample preparation and analysis even for complex samples. Samples are prepared in a simple and safe manner combining accurate results with high throughput.

Automation – made easy!

GERSTEL automated SPE based on the MPS autosampler provides integrated method for SPE and GC/MS or LC/MS analysis for simple and error-free control of the complete system.

The MPS is a fully automated sample preparation and sample introduction robot for GC/MS and LC/MS. The complete system is easily and efficiently controlled from the Agilent ChemStation software or from the GERSTEL MAESTRO software.

Sample preparation steps are selected by mouse-click from a simple pull-down menu and can easily be combined with automated SPE:

• Dilution and standard addition
• Automated weighing, centrifugation and sonication
• Derivatization before or after solid phase extraction
• Heated or cooled conditioning and mixing

One method and one sequence table control the complete system including sample preparation and GC/MS or LC/MS analysis.

Easy transfer or your established manual methods

• Ther GERSTEL SPE is based on standard 1 mL, 3 mL, and 6 mL SPE cartridges fitted with transport adapters. Standard cartridges pre-mounted with transport adapters are readily available from several leading suppliers. Manual SPE methods can be directly transferred to the MPS and automated.

High throughput

• Analysis of up to 98 samples including sample preparation using standard SPE cartridges.

Efficient

• All sample preparation steps are performed during GC/MS or LC/MS analysis of the preceding sample for highest productivity system utilization.

Optimized timing for each and every sample

• All samples receive identical treatment for best reproducibility. Sample introduction to the GC/MS or LC/MS system follows immediately after sample preparation.

Highly controlled analysis conditions

• Defined volumes and constant flow rates provide highly reproducible conditions and optimal results independent of variations in sample matrix.

Internal Standard Addition

• Automated liquid standard additional provides improved Quality Assurance.

Contamination free

• Transfer of eluent from the SPE cartridge to the sealed sample vial is performed using a disposable syringe needle, eliminating the risk of carry over.

Simple concept, highly rugged and efficient

• Conditioning, extraction and elution of the cartridge is performed in one dedicated module with minimal movement of the cartrdige ensuring highest efficiency and ruggedness.

Evoprative concentration in the GERSTEL SPE

• After removing unwanted sample material and transferring the clean extract to the collection vial during the SPE process, the GERSTEL SPE can further perform an evaporative concentration step if needed.

The eluate can be concentrated inside the collection vial while in the SPE station. A controlled flow of inert gas is allowed to purge the vial while keeping it at a user-defined temperature for best possible results. The vial can be agitated at a user-defined rate to speed up the evaporation process. A keeper solvent can be added automatically before, during or after evaporation in order to minimize loss of analytes or in order to change over to an LC- or GC-compatible solvent for the ensuring analysis. This enables complete automation of sample preparation and sample introduction even if the SPE eluent is not compatible with the LC- or GC column or analysis conditions.

Your benefits:

• Lower detection limits are achieved by adding an automated concentration step
• Accurate quantification ensured by applying highly controlled conditions
• Simple change-over between eluent and GC- or LC-compatible solvent enables the use of optimal SPE conditions without compromising the quality of separation and analyte detection.
• Best possible throughput and system utilization through full automation.

Numerous standard sample preparation procedures for chromatographic methods, according to accepted laboratory procedures, are based on liquid-liquid extraction (LLE), even though this technique is marred by several disadvantages: many steps are difficult to automate and relatively large volumes of, sometime toxic, organic solvent are involved.

The extract must sometimes be cleaned up in several stages, concentrated and evaporated, in order to achieve adequate detection limits. Membrane Assisted Solvent Extraction MASE is an alternative to LLE: It is based on small-scale LLE with a low density polyethylene (LDPE) membrane separating the aqueous sample from the organic solvent. MASE can be performed fully automated by the MultiPurpose Sampler MPS and embedded into sample preperation procedures. Extracts can be directly injected into GC or GC/MS systems by Large Volume Injection LVI.

The process was developed by UFZ Leipzig-Hallel GmbH in close cooperation with GERSTEL.

Twister Back Extraction (TBE) offers:

• Extraction, enrichment and analysis of high boiling or thermally labile compounds
• Combination of Stir Bar Sorptive Extraction (SBSE) and LC or LC/MS

A key element of the method is the use of both PDMS- and EG-Silicone Twister in one vial and the simultaneous desorption of both Twister combined into a single GC/MS run. While the PDMS Twister stirs the sample extracting non-polar to medium polarity compounds, the EG-Silicone Twister is held in position on the inside wall of the vial by the Twicester clip. The EG-Silicone Twister very efficiently extracts more polar compounds that form hydrogen bonds as hydrogen donors, for example phenols. Twicester can be used to place Twisters in the liquid phase or in the headspace as required.

mSBSE using the GERSTEL Twicester® enables the determination of compounds over a wide polarity range in just one step.

GERSTEL Twicester® Benefits

• Longer life-expectancy of the EG-Silicone sorben surface since it doesn’t perform active stirring during extraction.
• No sample to sample carry-over, only the Twisters are in contact with the sample.

Multi-Stir Bar Sorptive Extraction (mSBSE)

• Simple solution for parallel extraction of a sample with multiple Twisters using the Twicester®
• Extraction over a wide polarity range using different Twister phases in parallel
• Improved recoveries and limits of detection by using multiple Twisters in parallel

Simultaneous Thermal Desorption of multiple Twisters

• Determination of all extracted compounds in one representative chromatogram
• Improved limits of detection through desorption of multiple Twisters for one GC/MS run