Index: Volume 2 Number 1
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100% Sample Recovery

After organic extraction, it is often difficult to recover the nucleic acid in the aqueous upper phase free from the denatured protein at the aqueous/organic phase interface. Phase-Guard™ a proprietary gel present during organic extractions migrates under centrifugal force to form a seal between the organic and aqueous phases. The organic phase and the interface material are effectively trapped below the Phase-Guard™ seal. This barrier allows complete, easy transfer of the entire aqueous phase, by simply decanting or pipetting to a fresh tube.

Eliminate Contamination

Adding PHASE-Guard™ to your protocol allows for quantitative collection of the entire aqueous phase, resulting in a 20-30% increase in nucleic acid recovery. PHASE-Guard™ virtually eliminates contamination of the sample with interface material thus improving the quality of the purified nucleic acid. PHASE-Guard™ also offers the researcher increased protection from exposure to hazardous compounds.

Single Tube Enzymatic Reactions

PHASE-Guard™ is inert, heat stable, and does not interfere with standard nucleic acid restriction and modification enzyme reactions. In fact, many of these reactions can be carried out directly in the 1.5 ml tubes containing PHASE-Guard™, terminated by the addition of phenol or phenol-chloroform and then extracted all in the same tube. PHASE-Guard™ can also be present in enzymatic reactions requiring a heat inactivation step.

Convenient Packaging

PHASE-Guard™ comes in two density formulations, Heavy and Light, and can be adapted to virtually any protocol requiring extraction with phenol and/or chloroform1 by selecting the formulation that is compatible with the aqueous and organic phases (Table 1). For your convenience PHASE-Guard™ is provided pre-dispensed into various standard lab centrifuge tubes for use with sample sizes ranging from 50 µl to 6 ml. By adding your sample to the PHASE-Guard™ tube, almost every standard laboratory procedure for nucleic acid isolation by aqueous/organic extraction (genomic DNA, plasmid DNA, phage or viral nucleic acid, etc.) is enhanced.

1. Murphy, N.R. and Hellwig, R.J. 1996 BioTechniques 21(5): 934-939.

Table 1: PHASE-Guard™ Application Compatibility Guide.