Q4ever™ Green *1250X DMSO Solution*

A real-time polymerase chain reaction (real-time PCR), also known as quantitative polymerase chain reaction (qPCR), is a popular laboratory technique of molecular biology based on the polymerase chain reaction (PCR). It monitors the amplification of a targeted DNA molecule during the PCR (i.e., in real time), not at its end, as in conventional PCR. Real-time PCR can be used quantitatively (quantitative real-time PCR) and semi-quantitatively (i.e., above/below a certain amount of DNA molecules) (semi-quantitative real-time PCR). There are two common methods for the detection of PCR products in real-time PCR, including (1) non-specific fluorescent dyes that bind any double-stranded DNA; and (2) sequence-specific DNA probes consisting of oligonucleotides that are labelled with a fluorescent reporter, which permits detection only after hybridization of the probe with its complementary sequence. For the first method, there are two requirements for a DNA binding dye for real-time detection of PCR, i.e., (a). enhanced fluorescence when bound to double-stranded DNA; and (b). minimal inhibition of PCR. SYBR Green is predominantly used in a variety of qPCR applications. We have recently developed Q4ever™Green, a newer generation of SYBR Green, to address some limitations with SYBR Green, e.g., enzyme inhibition. Q4ever™Green permits the use of the Q4ever™Green in PCR with little PCR inhibition and enhanced sensitivity. Q4ever™Green can be used to monitor the amplification of any double-stranded DNA sequence. No probe is required, which can reduce assay setup and running costs, assuming that your PCR primers are well designed and your reaction is well characterized. As SYBR Green, the primary disadvantage is that it may generate false positive signals; i.e., because the Q4ever™Green dye binds to any double-stranded DNA. It can also bind to nonspecific double-stranded DNA sequences. It is extremely important to have well-designed primers that do not amplify non-target sequences, and that melt curve analysis be performed.

Page updated on September 1, 2025