PrepFiler™ Kits FAQs
Q: What is the PrepFiler™ kit?
A: The PrepFiler™ kit is a magnetic particle-based DNA extraction chemistry for isolation of high quality DNA from forensic samples.
Q: What makes the PrepFiler™ kit different from other magnetic particle or bead-based extraction methods?
A: The PrepFiler™ kit has been optimized to effectively bind the DNA in a complex with the PrepFiler magnetic particles to maximize DNA recovery and allow superior removal of inhibitors. This unique complex enables the efficient release of DNA during elution to deliver a superior yield of high quality DNA.
Q: How many samples can be processed using the PrepFiler™ kits?
A: For low to medium throughput laboratories, samples can be extracted using the manual kit. Each kit contains substrate removal devices and sufficient microfuge tubes for processing 100 samples. For labs requiring automation, a larger kit is available. Each of the automated kits contains 10 x 96- well PrepFiler filter plates (to remove substrates), 10 x 96 Processing Plates and enough PrepFiler reagents to process 960 samples on standard liquid handling platforms.
Q: What sample types have been extracted using the PrepFiler™ kit?
A: The PrepFiler™ kit has been used to successfully extract a variety of database and forensic-type samples including: dried body fluids (saliva, semen, blood) stains, liquid blood and other body fluids, lysed epithelial or sperm cell fractions, "touch" samples, hair roots, nail clippings, tissue and bone samples. Studies conducted during developmental validation and customer verification testing demonstrated the PrepFiler™ kit's ability to effectively isolate and remove inhibitors from challenging and compromised samples at a range of sample inputs.
Q: Will protocol modifications be required for certain sample types?
A: The PrepFiler™ kit has been optimized such that a single protocol works with most sample types. For certain types of challenging samples (such as tooth and bone samples), which require additional processing steps or procedural changes, suggested protocols are provided in the PrepFiler™ User Guide.
Q: Can the PrepFiler™ kit be automated and, if so, on which platforms?
A: Validated protocols and scripts are in development for automation of the PrepFiler™ kit chemistry on the Tecan Freedom EVO® liquid and magnetic particle handling platform as part of the HID EVOlution™ System. The validation of the automated protocols will be carried out on the Tecan Freedom EVO® 150 platform (the Tecan EVO® 200 will also be considered validated due to the similarities between worktable layouts). Customers wishing to automate on an alternative platform should consult the PrepFiler Forensic DNA Extraction Kit User Guide for information on the PrepFiler reagents, recommended protocols, and required materials and hardware. A 96-well Magnetic Ring Stand, heated shaker and PrepFiler™ kit plastics are recommended to ensure optimal performance of the chemistry on alternative platforms.
Q: Is the PrepFiler™ kit compatible with the existing Tecan HID EVOlution™ System?
A: The current HID EVOlution™ System for Quantifiler® kit set-up, normalization and AmpFℓSTR® kit PCR set-up uses a 4 channel liquid handling system with 4 small volume syringes. The PrepFiler™ kit automated protocol requires a liquid handling system with large volume syringes. Customers wishing to automate the PrepFiler™ kit using the HID EVOlution® System can purchase a new 8 channel configuration or upgrade an existing 4 channel system to a 4+4 channel configuration (4 small volume syringes plus 4 large volume syringes). Customers may also wish to have separate systems for extraction and PCR set-up/normalization in which case the 8 channel configuration for extraction is suggested.
Q: Are the plastics recommended for use with the PrepFiler™ kit certified as DNA-Free?
A: The plastics are not certified as DNA free but extensive testing of reagent blank extraction controls during the developmental validation of the PrepFiler™ kit has shown no incidences of detection of exogenous DNA.
Q: Can you UV treat the processing plates?
Q: Which aspects of the recommended protocol are most critical to achieve optimal results when extracting DNA using the PrepFiler™ kit?
A: It is important to follow all aspects of the recommended protocols for both manual and automated processing, but in particular when using the manual protocol, the user should take care not to shorten the lysis step or over-dry the pellet as this may reduce the quality and final yield of DNA.