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OnGuard II Cartridges

Remove Matrix Interferences for Better Performance in Many IC Applications

The OnGuard II Cartridges remove matrix interferences such as phenolics, metals, cations, anions, or hydrophobic substances encountered in many ion chromatography applications. These cartridges have wide pH stability and allow low level ion analysis. Cartridges are available in 1 cc and 2.5 cc high-capacity formats. Six select chemistries are now available in trial size packs of 12 cartridges (listed below).

Solve Tough Applications Problems

  • Facilitate better separations
  • Increase lifetimes of analytical columns
  • Solve major matrix problems
  • Achieve reproducible trace-level determinations in concentrated matrices

Optimized Design and Manufacture

The OnGuard II hardware is designed with Luer inlets for easy and secure connections. The cartridge design eliminates leaks and channeling. The unique sample distribution frit maximizes complete resin bed usage. The cartridge hardware is optimized for the best possible performance in matrix removal or concentration applications.

Guaranteed Performance

All OnGuard II products are shipped with a Certificate of Analysis verifying product capacity, performance, and cleanliness.

Convenient and Easy to Use

Samples are easy to process. Samples can be passed through the cleanup cartridge directly into the LC injector valve loop using a Luer-style syringe. Alternatively, samples can be processed in parallel using the OnGuard Sample Prep Station.

Versatile Selection of Resins (*Available in 12 cartridge packs)

  • OnGuard II A
  • OnGuard II Ag*
  • OnGuard II Ba*
  • OnGuard II H*
  • OnGuard II Na
  • OnGuard II M
  • OnGuard II P
  • OnGuard II RP*
  • OnGuard II Ag/H*
  • OnGuard II II Ba/Ag/H*

The OnGuard II family of sample pretreatment cartridges is available in a wide range of packings and in two sizes(1-cc and 2.5-cc) to fit your sample pretreatment needs. In addition, resins are available in the Auto OnGuard syringe barrel format for robotic processing as custom order products. The Summary tab contains a table summarizing the OnGuard products and their typical applications.

Cartridges can be used singly or in series depending on the matrix interferences to be removed. The OnGuard Ba, OnGuard Ag, and OnGuard H cartridges can be used in series to remove sulfate, chloride, and carbonate from a water sample prior to trace-level determination of bromate.

OnGuard II A Cartridge

OnGuard II A is used in the removal of anionic contaminants from sample matrices and for the neutralization of highly acidic samples.

OnGuard II Ag Cartridge

OnGuard II Ag removes chloride, bromide, and iodide from sample matrices.

OnGuard II Ag/H Cartridge

The OnGuard® II Ag/H cartridge removes chloride, bromide, and iodide from concentrated matrices such as brines.

OnGuard II Ba Cartridge

OnGuard II Ba removes high concentrations of sulfate from sample matrices.

OnGuard II Ba/Ag/H Cartridge

The OnGuard® II Ba/Ag/H is a layered cartridge containing OnGuard II Ba, Ag, and H styrene-based, sulfonic acid resins.

OnGuard II H Cartridge

OnGuard II H removes high levels of alkaline earth and transition metals from sample matrices and neutralizes highly alkaline samples such as sodium hydroxide or sodium carbonate.

OnGuard II M Cartridge

OnGuard II M is used for the removal of transition metals and for matrix elimination of alkali and alkaline earth metals.

OnGuard II Na Cartridge

OnGuard II Na removes high levels of alkaline earth and transition metals from sample matrices without acidifying the sample.

OnGuard II P Cartridge

OnGuard II P is recommended for removing the phenolic fraction of humic acids, tannic acids, lignins, anthocyanins, and azodyes from samples prior to analysis by ion exchange.

OnGuard II RP Cartridge

OnGuard II RP is recommended for removing hydrophobic substances such as aromatic dyes, some aromatic carboxylic acids, hydrocarbons, and surfactants from sample matrices.

OnGuard Accessories

OnGuard Sample Prep Station enables simultaneous pretreatment of multiple samples with OnGuard sample pretreatment cartridges.