Abstract: A method is provided for using a silanized silica matrix to isolate a target nucleic acids, such as plasmid DNA, fragments of DNA, chromosomal DNA, or RNA from contaminants, including proteins, lipids, cellular debris, or non-target nucleic acids. The silanized silica matrix comprises a silica based solid phase and a plurality of silane ligands covalently attached to the surface of the solid phase. Non-target material adsorbs to the silanized silica matrix in the presence of a sufficient concentration of chaotropic salt, while target nucleic acids adsorb to the matrix under other solution conditions. The method of using the silanized silica matrix of the present invention can be used to clear solutions of disrupted biological material, and to isolate nucleic acids therefrom or from other solutions containing nucleic acids and at least one contaminant.

Abstract: The present invention provides methods for isolating a defined quantity of DNA target material from other substances in a medium. The method may be carried out using a known quantity of a silica-containing solid support, such as silica magnetic particles, having a definable capacity for reversibly binding DNA target material, and DNA target material in excess of the binding capacity of the particles. The methods of the present invention involve forming a complex of the silica magnetic particles and the DNA target material in a mixture of the medium and particles, and separating the complex from the mixture using external magnetic force. The DNA target material may then be eluted from the complex. The quantity of DNA target material eluted may be determined based on a calibration model. The methods of the present invention permit isolation of DNA target material which is within a known quantity range.

Abstract: The present invention provides methods for isolating a defined quantity of DNA target material from other substances in a medium. The method may be carried out using a known quantity of a silica-containing solid support, such as silica magnetic particles, having a definable capacity for reversibly binding DNA target material, and DNA target material in excess of the binding capacity of the particles. The methods of the present invention involve forming a complex of the silica magnetic particles and the DNA target material in a mixture of the medium and particles, and separating the complex from the mixture using external magnetic force. The DNA target material may then be eluted from the complex. The quantity of DNA target material eluted may be determined based on a calibration model. The methods of the present invention permit isolation of DNA target material which is within a known quantity range.