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Threshold DNA Detection Assay

The Threshold DNA Detection Assay is used by pharmaceutical and biotechnology companies worldwide and is recognized by the FDA for DNA contaminate testing.

The Threshold™ Total DNA Assay quantitatively measures picograms of single-stranded DNA. Unlike hybridization techniques which require DNA probes or primers with a specific nucleic acid sequence, the Threshold Total DNA Assay measures DNA with broad sequence specificity. This enables the Threshold System to measure host cell DNA as well as other DNA that might have been introduced during the biopharmaceutical manufacturing process. In addition, since the assay does not require sequence specific probes or primers, the Threshold Total DNA Assay can easily be applied to different samples purified from different host organisms. The assay consists of three steps, reaction stage, separation stage and detection stage. 

 

Reaction stage

total-dna kit-reaction components

In the reaction stage, streptavidin, biotinylated single-stranded DNA binding protein and anti-single stranded DNA antibody are incubated with the sample mixture containing the single stranded DNA to be measured.

total-dna-kit-reaction complex

The streptavidin, biotylinylated single stranded DNA binding protein and anti-single stranded DNA antibody and single stranded DNA in the sample mixture form a reaction complex that is independant of DNA sequence.

Separation Stage
total-dna-kit detection steage The reaction mixture containing the reaction complex is filtered through a biotinylated membrane.  By leveraging the strong affinity streptavidin has for biotin, the reaction complex is captured and concentrated on the membrane.

Detection Stage

total-dna-kit-separation The membrane with the captured reaction complex is placed in the Threshold System which contains the substrate urea.  The urea is hydrolyzed by urease producing a pH change that is detected by the systems light-addressable potentiometric sensor.  Urease activity from up to eight different samples can simultaneouly measured on the Threshold system.

 

Established for over 10 years, Threshold Total DNA Assay is used by pharmaceutical and biotechnology companies worldwide and is recognized by the FDA for DNA contaminate testing. Using the Total DNA Assay Kit, the following applications have been demonstrated.

Quantitation of residual DNA in final product, biopharmaceuticals using the Threshold Total DNA Assay System. Assay validation and determination of detection limit. To learn more (link to application note: Quantitation of residual DNA in final product biopharmaceuticals using the Threshold DNA assay system. Assay validation and determination of detection limit.)


R9010

DNA Starter Kit  Includes:   (1) Total DNA Assay Kit,   (100) Sarstedt 2 ml test tubes  (100) biopure pipette tips 1 ml  (100) biopure pipette tips 200

R9004 DNA BULK KIT

DNA Bulk Kit (R8010/R8007) 800 determinations  Includes:   (104) Threshold Sticks   (20) Threshold Blank Sticks   (66) Zero Calibrator   (20) Positive Control   (20) High Calibrator   (100) DNA Labeling Reagens  (13) Reconstitution Buffer   (10) Substrate Concentrate   (19) Wash Solutions   (13) Filter Unit Kits (104 units)  

R9009 DNA KIT

Total DNA Assay Kit (R8010/R8007) 64 determinations  Includes:   (10) Threshold Sticks  (6) Zero Calibrator   (2) Positive Control   (2) High Calibrator   (8) DNA Labeling Reagens  (1) Reconstitution Buffer   (1) Substrate Concentrate   (2) Wash Solutions   (1) Filter Unit Kits (8 units)

R9016

Threshold DNA kit without filter

R9015

Threshold DNA Bulk Kit without filter

R8003

Threshold Sticks, Biotinylated   Box of 20, 160 determinations

R8004

 

Threshold DNA Zero Calibrator Includes:   (10) Zero Calibrator Vials 10 ml