share:
article_image

Keep Your Instruments Up and Running with CarboPrep Plus SPE Cartridges

  • Maximum Contaminant Removal
  • Less Instrument Downtime
  • Higher Sample Throughput

Four Words No Environmental Lab Manager Wants to Hear: “The Instrument is Down.”


If you are in charge of an environmental lab, you know that instruments that are down for unscheduled maintenance due to inlet or column contamination are not only costing money instead of making it, but are also jeopardizing your ability to meet your customers’ deadlines and performance requirements.

Chances are, you are also in charge of the lab that prepares samples for analysis, so you appreciate the value in making that process simple, reproducible, and effective, mitigating the chance for error and providing a clean extract that won’t shut an instrument down in the analytical lab because of inlet-fouling matrix components that made their way through the sample cleanup process.

Unfortunately, for the analysis of organochlorine pesticides in soil and water, the industry standard sample preparation product—activated Florisil SPE cartridges—just isn’t up to the job of removing the worst of those sample matrix contaminants that condense inside inlet liners or coat the inlet side of your analytical column. Florisil is great for stopping polar compounds, but those usually aren’t the compounds that cause instruments to fail their calibration checks, requiring unscheduled maintenance, delaying processing new samples, and adding the expense of replacing consumables ahead of schedule.

If your samples may contain those relatively high molecular weight sample matrix compounds that are the bane of injection ports and sensitive analytes, you’ll need something different. Fortunately, new Resprep CarboPrep Plus SPE cartridges outperform Florisil cartridges in removing these troublesome compounds, protecting your system and keeping samples running through your lab efficiently.

Figure 1: CarboPrep Plus cartridges kept the instrument running more than twice as long as the instrument analyzing samples cleaned with Florisil cartridges.

Graph analyzing samples

An Easy Change for the Sample Prep Lab

To remove the matrix components that contaminate your inlets and degrade your analytes of interest, you need a sample prep product with a different selectivity than Florisil that still allows all the target analytes to elute. But, chances are, your lab is set up to run a standard Florisil cleanup and switching to a new process can be a logistical challenge.

To make the switch to another SPE product easier, Restek’s CarboPrep Plus cartridges use the same equipment, solvents, and solvent volumes that work for Florisil, but the specially treated carbon in the CarboPrep Plus tubes will do a much better job of removing those inlet-contaminating matrix components that may be present in your customers’ samples.

While the CarboPrep Plus SPE cartridges have different selectivity than activated Florisil cartridges, they will still elute the compounds of interest and remove contaminating compounds using the same procedure. Change doesn’t get easier than that.

Figure 2: CarboPrep Plus SPE cartridges use the same solvents, solvent volumes, and extraction manifolds used in a standard Florisil procedure, but the difference in cleanup is obviously improved visually and chromatographically.

Comparing CarboPrep Plus vs. Florisil Cleanup for the Analysis of Organochlorine Pesticides by Electron Capture Detector


CarboPrep Plus SPE Cartridges

Rock-Solid Reliability Also Benefits the Analytical Lab

A proprietary treatment renders the carbon in CarboPrep Plus SPE cartridges clean and consistent, allowing you to standardize on an extraction protocol and not have to optimize elution volumes for every new batch of cartridges. This simplifies workflow in the sample prep lab and provides confidence that the next cartridge will perform exactly the same as the last. The analytical lab also benefits from a CarboPrep Plus cleanup because less downtime is required for maintenance, and high recoveries and low background levels are consistently obtained (Table I). Less maintenance and excellent analytical performance mean higher sample throughput for your lab.

Table I: Accurate, consistent recoveries for organochlorine pesticides and surrogate compounds (TCMX and DCB) make switching to CarboPrep Plus cartridges an easy way to improve analytical performance.

Compound

Average % Recovery*

% RSD

TCMX

99.8

1.3

hexachlorobenzene

97.6

2.3

alpha-BHC

99.2

1.3

gamma-BHC

98.1

1.4

beta-BHC

98.7

1.4

delta-BHC

98.7

1.7

heptachlor

101.2

1.7

aldrin

97.1

1.7

heptachlor epoxide

98.6

1.6

gamma-chlordane

98.2

1.8

alpha-chlordane

96.9

2.2

4,4’-DDE

96.8

1.6

endosulfan I

98.0

1.4

dieldrin

97.8

1.4

endrin

98.4

1.6

4,4’-DDD

97.4

1.4

endosulfan II

94.6

5.5

4,4’-DDT

98.2

1.2

endrin aldehyde

96.1

1.2

methoxychlor

100.2

2.1

endosulfan sulfate

97.1

2.2

endrin ketone

98.1

0.8

DCB

97.8

2.2

* n = the analysis of 6 cartridges each from 3 different lots for a total of 18 data points


Figure 3: Lot-to-lot consistency ensures that all the compounds of interest will elute within the 10 mL collection volume used for typical cleanup procedures, ensuring excellent recoveries time and again. In this figure, you can see a subset of organochlorine pesticides that are retained to different degrees on CarboPrep Plus material, and even hexachlorobenzene, the most highly retained compound, showed consistently high recovery at 97.6% (2.3% RSD, Table I). Note that all compounds listed in Table I elute from CarboPrep Plus cartridges prior to tetrachlorometaxylene (TCMX), so elution volumes can be reduced to save time for labs not analyzing hexachlorobenzene.

Lot-to-Lot consistency

Figure 4: CarboPrep Plus cartridges are made using proprietary treatment and strict in-house manufacturing controls that result in exceptionally low background, cartridge after cartridge, and lot after lot.

Peaks
1.2,4,5,6-Tetrachloro-m-xylene (TCMX)
Peaks
2.Decachlorobiphenyl (DCB)
Resprep CarboPrep Plus SPE Cartridge (Lot 1221 Comparison)
GC_EV1493
ColumnRtx-CLPesticides, 30 m, 0.32 mm ID, 0.32 µm (cat.# 11141)
Sample2,4,5,6-Tetrachloro-m-xylene (cat.# 32027)
Decachlorobiphenyl (BZ #209) (cat.# 32029)
Diluent:Hexane
Conc.:2 ppb
Injection
Inj. Vol.:4 µL splitless (hold 0.75 min)
Liner:Topaz 4.0 mm ID single taper inlet liner w/wool (cat.# 23303)
Inj. Temp.:250 °C
Purge Flow:50 mL/min
Oven
Oven Temp.:90 °C (hold 0.5 min) to 330 °C at 25 °C/min (hold 2 min)
Carrier GasHe, constant flow
Flow Rate:3.5 mL/min
DetectorMicro-ECD @ 340 °C
Make-up Gas Flow Rate:50 mL/min
Make-up Gas Type:N2
Data Rate:50 Hz
InstrumentAgilent/HP6890 GC
NotesConditioned a Resprep CarboPrep Plus SPE cartridge (cat.# 25845) by adding one cartridge volume of hexane:acetone (90:10) and letting it stand for five minutes before drawing the solvent down to frit level. Then, 1 mL of sample extract was loaded onto the cartridge and eluted with 9 mL of hexane:acetone (90:10).

Make the Simple Switch to CarboPrep Plus SPE Cartridges and Improve Lab Productivity

If you have trouble with samples contaminating your GC inlets and columns, resulting in failing calibration checks for your organochlorine pesticides, unscheduled instrument maintenance, rework, delays, and unexpected expenses, then consider adding CarboPrep Plus cartridges to your toolbox of sample preparation options. While Florisil is excellent at removing polar matrix contaminants, the matrix contaminating compounds that foul inlets and columns pass through and end up in your instruments. To get consistent recoveries, while mitigating the risk that a dirty sample will take an instrument down, choose CarboPrep Plus SPE cartridges for your organochlorine pesticides workflow.

Order now at www.restek.com/CarboPrepPlus

Restek Domestic Customer Service

Subject

Message

Your Full Name

Your Email

Company Name

Address

Spam Block (Please leave this blank)

all fields required

Thank you

Your message has been sent. We will be in touch shortly.

Message not sent

Sorry, your message could not be sent at this time. Please try again later, or contact Restek or your local Restek representative via phone.

www.restek.com/Contact-Us