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how long should qPCR product be? - 150~250bp? (May/31/2006 )

When using the kit that requires the product to be at less than 500bp length, can I design the primers which priming a product about 450bp?

(However my teacher said product of 150~250bp is the best choice.)

Thank you for your reply:)


at less means 500bp max or 500bp min?...

If it's max, you can use dilution of the binding solution from your kit. Let goo dry, and elute with great volume . Then concentrate with butanol your sample (no salts needed)

If it's minimum, use twice the volume recomended by your kit and keep your flow through.


I wander what sort of PCR kit requires PCR product to be at less 500bp?

You teacher is true. In fact, for qPCR purpose, all you need is your target sequence is able to be amplify exponentially. So shorter amplicon consume less dNTP for each cycle, thus theorytically is more efficient compared to those 500bp or more.

I tried 92bp before