qPCR/Real-Time PCR

What is qPCR / Real-Time PCR?

Quantitative PCR (qPCR), also called real-time PCR, monitors DNA amplification as it happens by measuring fluorescent signal during each cycle, allowing quantification of the starting template amount rather than only confirming presence or absence at the reaction's end as in standard end-point PCR. The two dominant detection chemistries are SYBR Green (an intercalating dye that binds double-stranded DNA) and hydrolysis probe-based systems such as TaqMan, which use a fluorescently labelled, sequence-specific probe. Choose SYBR Green-based master mixes for flexible, cost-effective quantification across many targets without per-target probe design; choose probe-based (TaqMan-style) chemistry for higher specificity, multiplexing, and applications such as pathogen detection where specificity is critical.

What you will find:

• Real-time PCR Master Mixes: High-performance GreenFast and Probe-based formulations—including AzuraView™ Blue Mixes—optimized with LoRox, HiRox, and NoRox tracers for universal instrument compatibility.

• One-Step RT-qPCR Kits: Integrated systems like ZymoScript and AzuraQuant™ that combine reverse transcription and quantification in a single tube to minimize handling errors and maximize high-titer recovery.

How to Choose qPCR / Real-Time PCR Reagents

Detection Chemistry
SYBR Green I dye binds all double-stranded DNA non-specifically, with excitation and emission maxima around 494 nm and 521 nm, respectively -- specificity in SYBR-based assays comes primarily from primer design and is enhanced by pairing with a hot-start Taq. Hydrolysis probe-based (TaqMan-style) chemistry uses a dual-labelled probe that is cleaved during amplification, releasing a fluorescent signal only when the probe binds its specific target, offering higher specificity and multiplexing capability (multiple targets detected in one well using spectrally distinct probes).

Reference Dye Requirements
Some real-time PCR instruments require a passive reference dye, commonly ROX, for signal normalisation across wells. Confirm whether your instrument requires ROX and whether the chosen master mix includes it or requires it to be added separately.

One-Step vs. Two-Step for RNA Targets
For RNA quantification, one-step RT-qPCR kits combine reverse transcription and qPCR in a single tube and buffer, reducing handling and contamination risk. Two-step approaches -- separate cDNA synthesis followed by qPCR using a standard 2x qPCR master mix -- offer more flexibility when the same cDNA pool will be tested against multiple targets.

Hot-Start and Buffer Optimisation
Real-time PCR master mixes typically include a hot-start Taq polymerase and an optimised buffer system (sometimes with proprietary additives) to promote specific primer annealing, reduce non-specific amplification, and improve reproducibility across replicate wells.

Internal Controls and Multiplexing
Some qPCR kit formats include an optional internal control RNA or reference gene amplification in the same well as the target, allowing simultaneous monitoring of reverse transcription/amplification success and normalisation across samples.

Specifications Context

In SYBR Green-based qPCR, the dye intercalates into double-stranded DNA as it accumulates during amplification, with fluorescence increasing proportionally to product quantity; melt curve analysis after amplification can additionally confirm product specificity by its characteristic melting temperature. In probe-based qPCR, the 5'-3' exonuclease activity of the Taq polymerase cleaves the dual-labelled probe annealed to the target sequence, separating a fluorescent reporter from its quencher and generating a signal proportional to target abundance -- the basis of the widely used TaqMan probe system. Real-time PCR master mixes and one-step RT-qPCR kits are typically stored at −20 °C to −30 °C and protected from light, where fluorescent dyes are pre-included; lot-specific CoAs are available on request.

Achieve absolute quantitative accuracy—contact the MBP team today for a quote on our professional Real-Time PCR reagents.