More efficient yields for sensitive downstream analyses
The EZ1&2 DNA Investigator Kit provides optimized chemistries for automated DNA purification with more efficient yields. STR analysis shows higher peaks for more sensitive detection (see figure " Improved performance in STR analysis", see table "Relative STR peak heights with different protocols"). The higher peaks demonstrate the improved signal-to-noise ratio for highly sensitive detection and high performance in downstream applications. Comparison of peak heights in STR analysis showed recovery of 79% of the potential DNA yield (not shown). Optional elution in TE buffer gives comparable performance (see table "Relative STR peak heights with different protocols") and provides increased stability for long-term storage of small amounts of purified DNA. There were no dropouts (<50 relative fluorescent units for any of the 8 alleles investigated) for any of the samples processed (see table "Relative STR peak heights with different protocols").
Table. Relative STR peak heights with different protocols
Experiment |
Kit and card |
Protocol |
Elution |
Relative peak height |
No. of dropouts |
1 |
EZ1 DNA Tissue Kit and EZ1 DNA Forensic Card |
Trace |
Water |
100% |
0/8 |
1 |
EZ1 DNA Investigator Kit and Card |
Trace |
Water |
176% |
0/8 |
2 |
EZ1 DNA Investigator Kit and Card |
Trace |
Water |
100% |
0/8 |
2 |
EZ1 DNA Investigator Kit and Card |
Trace |
TE |
116% |
0/8 |
3 |
EZ1 DNA Investigator Kit and Card (200 µl) |
Trace |
Water |
100% |
0/8 |
3 |
EZ1 DNA Investigator Kit and Card (500 µl) |
Large-volume |
Water |
203% (81% normalized to starting volume) |
0/8 |
Control DNA was diluted in Buffer G2 to a final concentration of 5 pg/µl, and 200 µl (or 500 µl for the large-volume protocol) was processed using the indicated kits and protocols, with 50 µl elution volumes. Peak heights for 8 peaks were normalized within each experiment. (Data kindly provided by B. Bayer and K. Anslinger, Institute of Legal Medicine, Ludwig Maximilian University, Munich, Germany.)
Easier handling of solid materials with "tip dance" protocol
In addition to the standard trace protocol, an optional, fully automated "tip dance" protocol can be used, where the filter-tip moves back and forth relative to the worktable platform while pipetting. This enables processing of solid materials, such as swabs, fabrics, blood discs, or cigarette butts, directly in the sample tube. There is no need for prior centrifugation to remove solid materials that could clog the tip (see flowchart " EZ1 DNA tissue trace and “tip dance” protocols"). The "tip dance" protocol simplifies handling and, in some cases, increases DNA yield with more efficient extraction of the sample (see figure " Easy and efficient processing of solid materials with the "tip dance" protocol").
Optimized protocol for larger sample volumes
A large-volume protocol enables fully automated processing of starting volumes up to 500 µl. This not only allows efficient DNA purification from dilute samples with low concentrations of DNA, such as diffuse stains, but also enables purification from samples that require larger volumes for thorough lysis. The ability to process larger sample volumes — with the same elution volume as the standard trace protocol — enables higher yields of more concentrated DNA for greater sensitivity in downstream applications (see figure " Higher yields of concentrated DNA with the large-volume protocol", see table "Relative STR peak heights with different protocols").
Efficient purification of low amounts of DNA
The EZ1&2 DNA Investigator Kit includes carrier RNA for increased efficiency. Carrier RNA enhances binding of DNA to the silica surface of the magnetic particles, especially if the sample contains low amounts of DNA (<1 ng). Published data suggest that addition of carrier RNA enables more efficient isolation of low amounts of DNA from forensic samples and may, for some sample types, provide improved DNA yields. Addition of carrier RNA to sample lysates did not interfere with downstream STR analysis.
Equivalence testing
Results from equivalence testing show that the EZ2 Connect Fx provides excellent DNA yields across a range of input sample dilutions, similar to the EZ1 Advanced XL (see figure Same excellent DNA yield when compared with the EZ1 Advanced XL).
Easy protocol setup and handling
Easy access to dedicated pre-loaded human ID and forensics protocols is available via the intuitive touchscreen interface on the EZ2 Connect Fx. For the EZ1 Instrument series, the preprogrammed EZ1 Advanced XL DNA Investigator Card (for use with the EZ1 Advanced XL), EZ1 Advanced DNA Investigator Card (for use with the EZ1 Advanced) and EZ1 DNA Investigator Card (for use with the BioRobot EZ1) make setting up the purification protocols as easy as making a credit card transaction. Prefilled, sealed reagent cartridges in the EZ1&2 DNA Investigator Kit help to prevent human error during setup of the instrument and prevent contamination of buffers. By eliminating human error in reagent preparation and workstation setup, and by providing cross-contamination-free liquid handling, the EZ2 Connect Fx, EZ1 Advanced XL, EZ1 Advanced, and BioRobot EZ1 provide high levels of reliability and standardization.
Quality guaranteed
In accordance with QIAGEN's ISO-certified Quality Management System, each lot of EZ1&2 DNA Investigator Kits is tested against predetermined specifications to ensure consistent product quality. The EZ1&2 DNA Investigator Kit meets ISO 18385 requirements.