What is the intended use of AMPLIRUN® controls?
Vircell AMPLIRUN® controls are designed as positive controls for conventional PCR or Real-Time PCR assays, facilitating the validation and monitoring of your molecular diagnostic systems.
What do AMPLIRUN® controls contain?
These molecular controls include complete and purified DNA or RNA of the indicated microorganism. This allows amplification with any specific primer pair. The only exception is the PARVOVIRUS B19 control (MBC080), which is based on a plasmid with a specific gene and primers included.
What is the volume of AMPLIRUN® products?
The products are lyophilised and must be reconstituted:
- DNA controls → 100 µl
- RNA controls → 50 µl
What is the shelf life of Vircell PCR controls?
The shelf life of Vircell PCR controls is 30 months for DNA and 24 months for RNA from the date of manufacture; as long as the storage recommendations described in the instructions for use of the product are observed.
Are they compatible with different PCR platforms such as Smart Cycler, Light Cycler or Cobas Amplicor?
Yes, Vircell DNA/RNA controls can be used on any nucleic acid amplification platform. The performance of our controls has been proven to be maintained regardless of the type of platform on which the technique is performed. It is not recommended to use DNA/RNA controls on platforms that perform nucleic acid extraction.
Do Vircell PCR controls require extraction prior to use?
No, pre-extraction is not required as the controls include purified nucleic acids, ready to be used directly in the amplification reaction.
How should they be stored?
PCR controls are supplied lyophilised and, under these conditions, should be stored refrigerated (2-8°C). Once reconstituted, DNA controls should be stored at temperatures between -5 and -40ºC, while RNA requires temperatures between -70 and -90ºC. Vircell recommends making aliquots of the material after reconstitution to avoid potential freeze/thaw problems associated with reusing the same vial multiple times. The response of the controls to repeated freeze/thaw cycles has been tested, and both DNA and RNA remain stable. However, we recommend that users avoid unnecessary freeze/thaw cycles in order to avoid possible degradation or contamination of the controls.
Is it advisable to store dilutions of AMPLIRUN® controls?
As detailed in the instructions for use of the product, it is advisable to store aliquots of the controls to avoid unnecessary freeze/thaw cycles. If a lower concentration of the control is required, dilutions of the controls can be made and stored for a period of time, although our recommendation is never to store dilutions with a concentration of less than 1000 copies/µl as a reduction in the number of copies has been observed after prolonged storage or successive freeze/thaw cycles. If a lower concentration than that stated in the control manual is required, the necessary dilutions should be prepared just before use.
What happens if, after using a specific control, the result obtained is too high for the requirements needed?
This is not a problem. After reconstituting the product according to the instructions for use of the product, it is possible to dilute the product to the concentration that best suits your requirements. However, care should be taken, especially with quantified controls, not to store very dilute aliquots (1000 copies/µl) as a reduced concentration is less stable to prolonged storage and freeze/thaw cycles and may alter the characteristics of the product.
Which controls can be used for quantitative PCR?
Yes, all AMPLIRUN® controls are quantified, which makes them ideal for qPCR. If you are in doubt about the level of quantification, please contact us.
Which quantification method has been used for the PCR controls quantified?
The quantification of our controls has been carried out by Real time PCR (Real time-PCR). The copy number was obtained using a specific sequence of the microorganism as a target. In real-time PCR quantification, a standard curve is used as a reference by comparing the amplification of a target sequence of the microorganism with a specific standard for each of the references quantified.
Is it advisable to freeze and thaw PCR controls and how many times can they be frozen and thawed without affecting the quality of the product?
Repeated freezing and thawing of PCR controls is not recommended as the quality of the product may be affected, especially when the genetic material is not highly concentrated (<1000 copies/µl). The influence of freezing and thawing on product quality will depend on the type of control, RNA being more easily degradable than DNA. In any case, it is difficult to set a maximum number of freeze/thaws that will guarantee the quality of the process. Therefore, it is more convenient to reconstitute the vial upon receipt and prepare aliquots before freezing.
Do they contain infectious material?
AMPLIRUN® products are not infectious because they only contain purified genetic material extracted from previously inactivated microorganisms. Vircell provides documentation certifying this issue upon request of its customers.
How much quantified control is recommended to use?
Vircell recommends using at least 1 µl of PCR control the first time it is used. In quantified controls 1 µl volume contains approximately 15000 copies of the microorganism, which allows up to 100 reactions to be performed with each vial. However, the user can prepare dilutions of the control and thus determine how many copies are needed to achieve a safe positive control in his PCR system. It is important to note that it is not advisable to use the controls at the detection limit (4 to 10 copies/control).
What are the advantages of Vircell PCR controls over those of other manufacturers?
Vircell PCR controls offer significant advantages over other manufacturers:
- Wide range of products including more than 120 infectious agents.
- Positive controls suitable for use in conventional PCR and Real Time PCR - any platform can be used
- Versatile product line: valid as amplification and extraction control
- Most of the controls are quantified
- Contain complete and purified DNA or RNA - any sequence can be amplified
- Controls obtained from whole micro-organisms
- Designed to avoid variability factors in PCR tests
- Lyophilised presentation avoids high transport costs and improves stability
- No need for dry ice for transport
- Competitively priced for clinical diagnostic use.
Are the nucleic acids encapsulated?
The PCR controls currently in our catalogue are not encapsulated, but contain the complete, purified genetic material of the microorganism ready for use in amplification reactions.
What advantages do they offer compared to a positive control from a clinical sample?
The use of Vircell PCR controls avoids the main challenges faced by laboratories using their own in-house controls:
- Limited quantity available
- Difficulty in obtaining positive samples on esoteric or less frequent parameters
- Non-standardised results; inconsistency between batches
- Non-purified controls - presence of human or other micro-organism genetic material
- Risk associated with working with infectious agents
- Reduced stability
The use of commercial PCR controls avoids these difficulties and provides advantages in terms of ease of use, long-term storability, standardisation, quality and consistency. In addition, laboratories in some countries are mandated to use commercial controls by quality accreditation groups.