I would like to calibrate my Real-Time PCR instrument with a custom dye, which buffer should I use?
Please ask your dye manufacturer for recommendations. If there is no specific recommendation available, try TE Buffer (pH 8.0) to start.
I need to see all the primer and probe sequences from an assay design right away. How can I do this?
You can directly see all the primer and probe sequences from a test design right away using the Primer Express Software. Open the software and choose File => New. Choose either TaqMan MGB Quantification or TaqMan Quantification for Gene Expression Assay design. Copy/paste your gene sequence of interest into the new window and click on the green triangle to get primer/probe designs.
Find additional tips, troubleshooting help, and resources within our Real-Time PCR and Digital PCR Instruments Support Center.
How can I determine whether the Tm of my custom probe is appropriate?
In general, the target Tm of a TaqMan probe is 70 degrees C. Using the Primer Express Software, you can check the Tm of a MGB or TAMRA probe probe.
Within the software, go to Primer Probe Test Tool and then copy/paste in your sequence of interest to see the Tm. If you need to check for a MGB based probe, make sure to choose Document Type: TaqMan MGB Quantification. If you need to check for a QSY or TAMRA based probe, make sure to choose Document Type: TaqMan Quantification.
Real-Time PCR and Digital PCR Applications
Find additional tips, troubleshooting help, and resources within our Real-Time PCR and Digital PCR Applications Support Center.
I have purchased custom oligos (primers and probes) and I want to make a 20x working stock for a TaqMan assay, similar to the pre-designed assays. How do I dilute and mix my oligos to make a 20x working stock?
Most pre-designed TaqMan assays are supplied as a 20x assay concentrate containing 18 uM of each primer and 5 uM of probe which provides a 900 nM of each primer and 250 nM of the probe (for gene expression assays) and 200 nM of each probe (for SNP genotyping assays) at the final 1x concentration.
In order to make a 20x working stock from custom oligos, the oligos need to be diluted as follows: To make a 20x Assay stock for Gene Expression assays, make 100 uM stocks of both forward and reverse primers, and TaqMan probe. Add 18 ul of each primer and 5 ul of the TaqMan probe, which gives 41 ul volume. Add 59 ul of 1X TE to bring the volume to 100 ul of 20X TaqMan Gene Expression Assay. To make a 20x Assay stock for a Genotyping Assay, make 100 uM stocks of both forward and reverse primers, and both TaqMan probes. Add 18 ul of each primer and 4 ul of each TaqMan probe, which gives 44 ul volume. Add 56 ul of 1X TE to bring the volume to 100 ul of 20X TaqMan SNP Genotyping Assays.