Welch Columns

Ultisil XB Series

Ultisil XB Series HPLC Columns are based on ultra-pure ( purity > 99.999% ) spherical and totally porous silica, unique bonding chemistry and proprietary surface modification techniques, producing excellent peak shape, column efficiency and exceptional lot-to-lot reproducibility. Ultisil column is the best choice for method development, owing to complete bonding chemistries and stable performance.

Features

• Ultra-pure spherical porous silica, purity > 99.999%
• Wide pH range: 1.5 – 10
• High efficiency: theoretical plate > 80000/m
• Excellent peak symmetry: tailing factor = 0.95~1.05
• Exceptional lot-to-lot reproducibility

Product Availability and Specifications

Ultisil Specialized

This specialized set of C18 phases is designed to offer nuanced differences from traditional C18/ODS phases. For example, Ultisil AQ-C18 and Ultisil ODS-3 will perform well even with 100% aqueous mobile phase; Ultisil Plus C18 is double-end-capped; Ultisil XS-C18 is high-carbon-loaded, improving its steric hindrance selectivity. Also see specialized C18 phases for Polynuclear Aromatic Hydrocarbons (PAH) and Amino Acid analysis.

Product Availability and Specifications

Column	USP	pH range	Carbon load (%)	Surface area (m2/g)	Endcapped	Phase Structure
Ultisil AQ-C18	L1	1.5 – 10.0	12% (120 A°)	320 (120 A°)	Yes
Ultisil Polar-RP	L1	1.5 – 10.0	18% (120 A°)	320 (120 A°)	Yes
Ultisil Amino Acid	L1	1.5 – 10.0	17% (120 A°)	320 (120 A°)	Yes
Ultisil LP-C18	L1	0.5 – 8.0	10% (120 A°), 5% (300 A°)	320 (120 A°), 90 (300 A°)	No
Ultisil LP-C8	L7	1.0 – 8.0	5.5% (120 A°), 3% (300 A°)	320 (120 A°), 90 (300 A°)	No
Ultisil LP-AQ	L1/L96	0.5 – 8.0	5% (120 A°)	320 (120 A°)	No
Ultisil PFP	L11	1.5 – 10.0	12% (120 A°)	320 (120 A°)	Yes
Ultisil Diol	L20	2.0 – 8.0	2.5% (120 A°)	320 (120 A°)	No

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The Xtimate Series columns based on hybrid silica-polymer packing materials and those based on pure polymer media, as well as size exclusion (SEC) columns.

Xtimate Silica Based HPLC Column

      X features of Xtimate column

• eXtra pH range: wide pH range from 1.0 to 12.5, excellent peak shape for strong bases
• eXtra column lifetime: 5 times of similar product such as Gemini
• eXtra performance: column efficiency of 5µm columns is as high as 90000/m, 2-3 times of that of Xterra
• eXtra care from Welch: enjoy excellent pre-sales and after-sales service from Welch

Comparison of Peak Shape After Soaking In Base

Lifetime Test Comparison: 5 Times Longer Than Gemini

Product Availability and Specifications

Xtimate® Polymer Based Column

Xtimate® polymer-based columns are based on polystyrene-divinylbenzene (PS-DVB), and can be applied for analysis of organic acids, mixed alcohols and sugar products.

• Xtimate Sugar-H is a special column designed for Ribavirin. Packed with H⁺ modified low-linking polystyrene-divinybenzene spheres (PS-DVB), this column can be applied for the analysis of organic acids and mixed alcohols.
• Xtimate Sugar-Ca is a strong cation exchange column packed with Ca²⁺ modified PS-DVB resins;can be used for the analysis of sugar products.
• Xtimate PS/DVB is based on polystyrene-divinybenzene. This column can be used in extreme conditions( pH 1-14).

Product Availability and Specifications

Application

Mannitol

Xtimate SEC

Xtimate SEC (size exclusion chromatography) is a double bonding mechanism, which makes possible of nonspecific adsorption of high Mw polymers, proteins, biological enzymes, polypeptides and other biological samples, can be applied to separating water-soluble polymers from biomacromolecules.

Features

• Ultra-high purity, stable silica bonded with hydrophilic polymer and diol functional groups.
• 5 µm or 3 µm silica microsphere, high separation efficiency
• 120 Å minibore columns fit for analysis of polar compounds such as cephalosporins; 300Å ones fit for biomacromolecules such as proteins and polypeptides.
• Five pore sizes: 120 Å, 300 Å, 500 Å, 700 Å and 1000 Å

Product Availability and Specifications

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Welch Boltimate core-shell HPLC column particle size is 2.7 µm, which consists of 1.7 µm solid core and 0.5 µm porous layer (porous shell). This kind of column can provide sub-2 µm efficiencies (~200000 p/m) and high resolution at much lower back pressure. Boltimate core-shell column can be used on both HPLC and UHPLC system, and method optimization is also very easy.

Features

• Provide sub-2 µm efficiencies (~200000 p/m) and ultra-high resolution at much lower back pressure
• Ultra fast separation
• Compatible with both HPLC and UHPLC system
• Narrow particle size distribution
• A standard 2 µm inlet firt is used to resist plugging with dirty samples, suitable for complex sample
• A variety of bonding phases provide different selectivities, excellent peak shape and lot-to-lot reproducibility
• Maximum pressure: 600 bar

Compared with traditional porous HPLC columns, Boltimate core-shell column has the narrower particle size distribution, which provides higher column efficiency, higher resolution and lower back pressure.

Product Availability and Specifications

Guideline selection

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Topsil® series HPLC column is a next-generation column by Welch, besides Ultisil® and Xtimate®. This series use different silica and provide different selectivity.

Features

• High purity silica (99.99%) with 150 Å pore size and 260 m2 /g surface area
• 12% carbon loading for C18 phase
• Because of large pore and moderate carbon loading, Topsil® C18 phase can also be used as AQ-C18 without phase collapse
• Endcapped for excellent peak shape and lifetime
• Lower back pressure than Ultisil®, almost the same column efficiency as Ultisil®
• Good for small molecules and peptides
• Topsil phases including C18, C8, Phenyl-Hexyl, Silica, NH2 and CN

Applications

Vitamin D3

Product Availability and Specifications

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UHPLC users have access to a number of high performance choices, including a selection of Ultisil UHPLC (1.8 micron) phases with overlapping selectivity; Xtimate Hybrid UHPLC phases (C18 and C8); and Welch inline filters and guard columns designed for UHPLC applications. 

All Welch UHPLC columns feature

• Ultra resolution: same resolution as or better than that of conventional column which has more packing materials
• Ultra speed: UHPLC offers more information per unit time and higher speed owing to its smaller particles.
• Sensitivity: higher N, narrower peak width (W), higher peak height. The system sensitivity of 1.8 µm UHPLC is 70% and 40% higher than that of conventional column of 5µm and 3.5µm packings, respectively.

Hardware Features

Product Availability and Specifications

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