[ROSETTA]

Hi, can someone please confirm if pseudo reverse phase occurs when we have a silica gel column, and we use a high concentration of organic modifier in the mobile phase, and only a small amount of water.  If this is the case, is this the same as HILIC chromatography, or am I getting confused, between the two
Hope someone can help
Thanks
Rosie

[Alpha-Omega]

Check out the Acclaim Mixed Mode columns at www.dionex.com.  Just typ in "mixed mode" in the search field upper right hand corner and you will get a tremendous amount of information regarding this material.

Attaching a data sheet....you can find this as well (scroll to bottom of page): 
http://www1.dionex.com/en-us/columns_accessories/spec/cons61873.html


Dionex Introduces the Acclaim Mixed-Mode HILIC-1 Silica-Based Column for Combined Reversed-Phase and Normal-Phase HPLC
 
 

June 2007, Sunnyvale, CA—Dionex Corporation announces the addition of a new mixed-mode HILIC column, empowering chromatographers to fully control the elution of both highly polar and nonpolar molecules. The Acclaim® Mixed-Mode HILIC-1 column is a unique silica-based mixed-mode stationary phase that combines both reversed-phase (RP) and hydrophilic interaction chromatography (HILIC) properties. This combination provides superior chromatographic properties, allowing chromatographers to optimize resolution of polar compounds that are otherwise unretained by reversed-phase chromatography.

The unique bonding chemistry of the Acclaim Mixed-Mode HILIC-1 provides superior performance compared to other commercially available diol columns. Its selectivity is orthogonal to RP columns, and it can operate in both RP and HILIC conditions. As a result, it has a broad range of applications in the chemical/petrochemical industry and life science laboratories.

Dionex (NASDAQ:DNEX) is a global leader in the manufacturing and marketing of liquid chromatography and extraction systems, consumables, and software for chemical analysis. The Company's systems are used worldwide in environmental analysis and by the life sciences, chemical, petrochemical, food and beverage, power generation, and electronics industries. Our expertise in applications and instrumentation helps analytical scientists to evaluate and develop pharmaceuticals, establish environmental regulations, and produce better industrial products.
 
As an additional note, you might be interested in some of these books: 

http://chemistry.about.com/od/chromatography/Chromatography.htm