Reversed phase HPLC is the most powerful and commonly used technique for the separation of pharmaceuticals. The mobile phases are usually a mixture of polar organic solvents and water. Separations can be isocratic or gradient and are based on analyte hydrophobicity - hydrophobic compounds are retained longer than polar compounds. A common issue with reversed phase separations is non-specific interactions between analytes and the column stationary phase. This undesired effect results from ionic interaction with un-reacted silanols or impurities in the silica gel. This non-specific interaction can cause peak tailing or adsorption. CTI’s AccuSil columns begin with exceptionally pure, highly characterized silica and use a proprietary bonding and end-capping techniques to eliminate free silanols. This results in columns with excellent peak shape and separation efficiency for all compounds including basic, neutral and acidic analytes.