How to choose an HPLC guard column

Updated 2026-11-11

A guard column is a short cartridge, packed with the same or a similar stationary phase, that sits in front of the analytical column. Manufacturers recommend it to intercept particulates and strongly retained contaminants before they reach the analytical column^{[1, 2]}, and replacing a cartridge is far cheaper than replacing the column itself^[3].

Three rules for choosing a guard

Same chemistry. Use the guard packed with the same phase as your column (for example a C18 guard for a C18 column) so selectivity is preserved^[1].
Compatible inner diameter and particle size. Guards are sold for specific column IDs; UHPLC columns need low-volume guards rated for UHPLC pressure.
Holder or fitting kit. Cartridge systems such as Agilent ZORBAX, Phenomenex SecurityGuard and Waters VanGuard need a holder or fitting kit the first time; after that you reorder cartridges only.

Guard matching table

This table uses the same matching rules as our product pages. Each analytical column links to its recommended guard and, where needed, the holder.

Analytical columns and matching guard cartridges
Analytical column(s)	Guard / holder	Part number	Price
Agilent ZORBAX Eclipse Plus C18 HPLC Column, 4.6 x 150 mm, 5 µm (`959993-902`) Agilent ZORBAX Eclipse Plus C18 HPLC Column, 4.6 x 250 mm, 5 µm (`959990-902`) Agilent ZORBAX Eclipse Plus C18 HPLC Column, 4.6 x 150 mm, 3.5 µm (`959963-902`)	Agilent ZORBAX Eclipse Plus C18 Guard Cartridges, 4.6 x 12.5 mm, 5 µm (4/pk)	`820950-936`	$280.80 USD
	Agilent ZORBAX High-Performance Guard Fitting Kit	`820999-901`	$340.20 USD
Agilent InfinityLab Poroshell 120 EC-C18 Column, 2.1 x 100 mm, 2.7 µm (`695775-902`) Agilent InfinityLab Poroshell 120 EC-C18 Column, 2.1 x 150 mm, 2.7 µm (`693775-902`)	Agilent InfinityLab Poroshell 120 EC-C18 UHPLC Guard, 2.1 x 5 mm, 2.7 µm (3/pk)	`821725-911`	$697.50 USD
Waters ACQUITY UPLC BEH C18 Column, 2.1 x 50 mm, 1.7 µm (`186002350`) Waters ACQUITY UPLC BEH C18 Column, 2.1 x 100 mm, 1.7 µm (`186002352`) Waters ACQUITY UPLC BEH C18 Column, 2.1 x 150 mm, 1.7 µm (`186002353`)	Waters ACQUITY UPLC BEH C18 VanGuard Pre-column, 2.1 x 5 mm, 1.7 µm (3/pk)	`186003975`	$882.00 USD
	Waters VanGuard Cartridge Holder	`186007949`	$186.30 USD
Phenomenex Luna C18(2) HPLC Column, 4.6 x 250 mm, 5 µm, 100 Å (`00G-4252-E0`) Phenomenex Luna C18(2) HPLC Column, 4.6 x 150 mm, 5 µm, 100 Å (`00F-4252-E0`) Phenomenex Gemini C18 HPLC Column, 4.6 x 150 mm, 5 µm, 110 Å (`00F-4435-E0`)	Phenomenex SecurityGuard C18 Cartridges, 4 x 3.0 mm ID (10/pk)	`AJ0-4287`	$691.34 USD
	Phenomenex SecurityGuard Guard Cartridge Kit (Holder)	`KJ0-4282`	$326.23 USD
Phenomenex Kinetex C18 Core-Shell Column, 4.6 x 150 mm, 2.6 µm, 100 Å (`00F-4462-E0`)	Phenomenex SecurityGuard ULTRA C18 Cartridges for 4.6 mm ID UHPLC Columns (3/pk)	`AJ0-8768`	$722.39 USD
Shodex SUGAR SC1011 Carbohydrate Column (Ca2+), 8.0 x 300 mm, 6 µm (`F6378102`)	Shodex SUGAR SC-G 6B Guard Column (Ca2+), 6.0 x 50 mm, 10 µm	`F6700090`	$648.00 USD
Shodex SUGAR KS-801 Column (Na+), 8.0 x 300 mm, 6 µm (`F6378010`) Shodex SUGAR KS-802 Column (Na+), 8.0 x 300 mm, 6 µm (`F6378020`)	Shodex SUGAR KS-G 6B Guard Column (Na+), 6.0 x 50 mm, 10 µm	`F6700020`	$648.00 USD
Shodex SUGAR SH1011 Organic Acid & Sugar Column (H+), 8.0 x 300 mm, 6 µm (`F6378100`)	Shodex SUGAR SH-G Guard Column (H+), 6.0 x 50 mm, 10 µm	`F6700080`	Quote
Shodex OHpak SB-806M HQ Aqueous SEC Column, 8.0 x 300 mm, 13 µm (`F6429106`) Shodex OHpak SB-804 HQ Aqueous SEC Column, 8.0 x 300 mm, 10 µm (`F6429103`) Shodex OHpak SB-803 HQ Aqueous SEC Column, 8.0 x 300 mm, 6 µm (`F6429102`)	Shodex OHpak SB-G 6B Guard Column, 6.0 x 50 mm, 10 µm	`F6709430`	$600.00 USD
Shodex GPC KF-806M Mixed-Bed GPC Column, 8.0 x 300 mm, 10 µm (`F6028090`) Shodex GPC KF-804L GPC Column, 8.0 x 300 mm, 7 µm (`F6027040`) Shodex GPC KF-803L GPC Column, 8.0 x 300 mm, 6 µm (`F6027030`)	Shodex GPC KF-G Guard Column, 4.6 x 10 mm, 8 µm	`F6700300`	Quote
Shodex PROTEIN KW-803 Aqueous SEC Column, 8.0 x 300 mm, 5 µm (`F6989103`) Shodex PROTEIN KW-802.5 Aqueous SEC Column, 8.0 x 300 mm, 5 µm (`F6989000`) Shodex PROTEIN KW-804 Aqueous SEC Column, 8.0 x 300 mm, 7 µm (`F6989104`)	Shodex PROTEIN KW-G Guard Column, 6.0 x 50 mm, 7 µm	`F6700131`	Quote

Column not listed?

Send us the analytical column part number through the quote form and we will confirm the matching guard. Combine the guard with an inline filter and filtered samples (see the syringe filter guide) for the longest column life. Browse all guard columns & cartridges.

Frequently asked questions

Does a guard column change my separation?

A guard packed with the same stationary phase as the analytical column adds a small amount of the same packing, so selectivity is preserved; it can slightly increase retention and back-pressure. Check system suitability after adding a guard to a validated method.

Guard column or inline filter?

An inline filter only removes particles. A guard cartridge removes particles and also retains strongly adsorbed sample components chemically, so it protects the column against fouling as well as blockage. Many labs use both.

When should I replace the guard cartridge?

Replace it when back-pressure rises, peaks broaden or split, or retention shifts and the problem disappears with the guard removed. Cleaner samples mean longer cartridge life.

Sources

Phenomenex: HPLC Guard Columns (Knowledge Center)
Agilent: Biomolecule Reversed-Phase LC Columns User Guide (operating tips)
Phenomenex: SecurityGuard Universal Guard Cartridge System

Specifications in the tables come from each product's source listing (linked on its product page). Always confirm critical limits against the manufacturer's current documentation.

Related categories & guides

Need a different dimension or phase? Send us the part number and we will quote it.