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USP column listing for HPLC columns
The following table lists columns that conform to the chromatography column classification set forth by the United States Pharmacopeia (USP) for grouping columns appropriate for reference procedures. For columns used in high-performance liquid chromatography (HPLC), columns are assigned a USP code starting with L, e.g. L1, L3, L7.
The USP L listing groups columns HPLC columns by characteristics of the stationary phase, however, requirements are broad enough to allow several columns in the same code despite having (possibly) vastly different performance. For example, USP code L1 calls for an octadecyl (C18) group bonded to silica or ceramic packing material, 1.5 to 10 µm in diameter, to which many C18 phases of varying carbon load, pore size, and surface area qualify. It is therefore still recommended to consult the actual application a column has been designed for after referring to its USP code as an initial guide.
GL Sciences offers columns for all major USP codes in common use today. GL Sciences InertSustain and Inertsil columns feature high-purity bonded silica phases providing separations with extremely low operating back pressure, high inertness, excellent efficiency and wide compatibility with solvents.
List of HPLC columns by USP code
| USP Code | Description | Phase |
L1 | Octadecyl silane chemically bonded to porous or nonporous silica or ceramic microparticles, 1.5 to 10 µm iSP Coden diameter, or a monolithic silica rod. | InertSustain C18 InertSustain AQ-C18 InertSustainSwift C18 InertSustain AX-C18 Inertsil ODS-HL Inertsil ODS-4 Inertsil ODS-3 Inertsil ODS-SP Inertsil ODS-P Inertsil ODS-2 Inertsil ODS Inertsil WP300 C18 |
L3 | Porous silica particles, 1.5 to 10 µm in diameter, or a monolithic silica rod. | |
L7 | Octylsilane chemically bonded to totally porous or superficially porous silica particles, 1.5 to 10 µm in diameter, or a monolithic silica rod. | |
L8 | An essentially monomolecular layer of aminopropylsilane chemically bonded to totally porous silica gel support, 1.5 to 10 µm in diameter, or a monolithic silica rod. | |
L9 | Irregular or spherical, totally porous silica gel having a chemically bonded, strongly acidic cation-exchange coating, 3 to10 µm in diameter. | Inertsil CX |
L10 | Nitrile groups chemically bonded to porous silica particles, 1.5 to 10 µm in diameter, or a monolithic silica rod. | |
L11 | Phenyl groups chemically bonded to porous silica particles, 1.5 to 10 µm in diameter, or a monolithic silica rod. | |
L13 | Trimethylsilane chemically bonded to porous silica particles, 3 to 10 µm in diameter. | Inertsil TMS |
L17 | Strong cation-exchange resin consisting of sulfonated cross-linked styrene-divinylbenzene copolymer in the hydrogen form, 6 to 12 µm in diameter. | InertSphere FA-1 |
L19 | Strong cation-exchange resin consisting of sulfonated cross-linked styrene-divinylbenzene copolymer in the calcium form, about 9 µm in diameter. | InertSphere Sugar-2 |
L20 | Dihydroxypropane groups chemically bonded to porous silica particles, 1.5 to 10 µm in diameter, or a monolithic silica rod. | |
L26 | Butyl silane chemically bonded to totally porous or superficially porous silica particles, 1.5 to 10 µm in diameter. | |
L33 | Packing having the capacity to separate dextrans by molecular size over a range of 4,000 to 500,000 Da. It is spherical, silica-based, and processed to provide pH stability. | |
L43 | Pentafluorophenyl groups chemically bonded to silica particles by a propyl spacer, 1.5 to 10 µm in diameter. | |
L62 | C30 silane bonded phase on a fully porous spherical silica, 3 to 15 µm in diameter. | |
L68 | Spherical, porous silica, 10 µm or less in diameter, the surface of which has been covalently modified with alkyl amide groups and not endcapped. | |
L78 | A silane ligand that consists of both reversed phase (an alkyl chain longer than C8) and anion-exchange (primary, secondary, or tertiary amino groups) functional groups chemically bonded to porous or non-porous silica or ceramic micro-particles, 1.0 to 50 µm in diameter, or a monolithic rod. | |
L96 | Alkyl chain, reversed-phase bonded totally or superficially porous silica designed to retain hydrophilic and other polar compounds when using highly aqueous mobile phases, including 100 % aqueous, 1.5 µm to 10 µm. | |
L118 | Aqueous polymerized C18 groups on silica particles, 1.2 to 5 μ m in diameter. | Inertsil ODS-P |