The polymerase chain reaction (PCR) has revolutionised methods for diagnostic testing as they are now extremely rapid to perform and are highly sensitive and specific
The use of rapid molecular methods, including PCR, is now routine in many laboratories in diverse areas such as food and environmental microbiological testing, forensics and clinical testing.
Such methods can easily lend themselves to automation for high throughput testing.
However, the introduction and implementation of PCR tests can generate a number of potential technical problems.
For instance, obtaining reproducibility of results between users and laboratories may be difficult in laboratories with no previous molecular experience.
Also, reducing the probability of false positive or negative results is an important issue for confidence in the test results.
The use of enhanced formulations of PCR reagents can offer significant advantages to laboratories by alleviating many of these potential technical pitfalls and offering greater flexibility.
Enhanced formulations of PCR can include premixed and/or pre-aliquoted reagents at multiple or single dose concentrations which can be in liquid, lyophilised or beaded formats.
Reagent mixes may include the basic PCR reaction components such as dNTPs, PCR buffer and MgCl2 and perhaps the Taq polymerase enzyme.
More sophisticated formulations can be fully customisable to the user's specific assay to include both primers, the user's preferred type of Taq polymerase and the reporting chemistry such as SYBR Green or fluorescent probes (eg, Taqman, Molecular Beacons).
Use of enhanced formulations of PCR reagents can provide easy entry to PCR for non-molecular biologists or untrained operators by greatly simplifying and standardising the set up of PCR reactions while still giving highly reproducible results.
These reagents can dramatically reduce the number of pipetting steps (and the associated pipetting errors) required per PCR reaction.
For some formulations only the test sample actually needs to be added prior to thermal cycling.
Additionally, enhanced formulations remove all the initial reagent preparation steps.
Pre-aliquoted reagents can help remove any product deterioration caused by repeated freeze/thawing of stock reagents and also reduce the potential for contamination of reagent stocks.
Most reagent mixes are fully optimised and the resulting PCR reactions are extremely robust and standardised.
Some generic and custom reagent formulations can give a great deal of flexibility to end users due to their suitability for a range of PCR types including end-point PCR and qPCR with fluorescent probes or dyes.
Q Chip, a developer of microencapsulation solutions, has launched a range of enhanced formulation PCR reagent beads called ReaX, an innovative gel-based bead for effortless PCR.
The new ReaX Mastermix range encapsulates all the reagents required to perform PCR in a single dose within a single bead.
Available in a variety of ready-to-use formats, ReaX Mastermix beads completely deskill, standardise and streamline set-up.
Subsequently PCR reactions are very robust and highly reproducible.
They can be used for end-point, qPCR and RT-PCR and with multiple fluorescent chemistries (eg, SYBR Green, TaqMan).
The Mastermix range is available for either 25ul or 50ul PCR reactions.
The only manipulations that laboratory users need to perform are to add their primers and sample to the reaction tube and then it is ready for the thermal cycler.
As well as the off-the-shelf ReaX range, Q Chip is also launching the ReaX Custom Bead Service whereby customers can specify exactly which primers, Taq polymerase (including Hot Start enzymes) and fluorescent chemistry they require in a ReaX bead which will be manufactured to the precise specifications.
This custom service provides customers with a high quality end-product and service tailored specifically to their individual needs.
All ReaX beads vary in size dependent on what reagents are encapsulated but they actually take up a small volume, typically less than 2ul of the total PCR reaction volume.
This means that the remaining reaction volume can be made up of sample.
This is obviously advantageous where target material is at a low level.
Another feature of the ReaX beads is that they can be stored and shipped at either 4C due to their highly stable nature therefore simplifying the reagent storage needs.
In addition, ReaX beads can reduce the overall test costs due to lower repeat rates and less reagent wastage.
