HotStarTaq Master Mix Kit

For highly specific amplification for any PCR application

Need bulk, customized or optimized products for commercial purposes? We also offer support with logistics, compliance and more. Reach out to cooperate with QIAGEN Strategic Partnerships & OEM
HotStarTaq Master Mix Kit (250 U)

Cat. No. / ID:  203443

3 x 0.85 ml HotStarTaq Master Mix (contains 250 units HotStarTaq DNA Polymerase, PCR Buffer with 3 mM MgCl2, and 400 µM of each dNTP)and 2 x 1.7 ml RNase-Free Water
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250 U
1000 U
2500 U
The HotStarTaq Master Mix Kit is intended for molecular biology applications. This product is not intended for the diagnosis, prevention, or treatment of a disease.
Need bulk, customized or optimized products for commercial purposes? We also offer support with logistics, compliance and more. Reach out to cooperate with QIAGEN Strategic Partnerships & OEM


  • High PCR specificity without the need for optimization
  • Easy reaction setup at room temperature
  • Ready-to-use master mix format reduces pipetting steps

Product Details

HotStarTaq Master Mix contains HotStarTaq DNA Polymerase, the unique QIAGEN PCR Buffer that minimizes the requirement for optimization, and dNTPs. Providing all components in a master mix reduces pipetting steps and the risk of contamination, while increasing throughput and reproducibility.


Each lot of HotStarTaq Master Mix Kit is subjected to a comprehensive range of quality control tests, including a stringent PCR specificity and reproducibility assay in which low-copy targets are amplified. HotStarTaq Master Mix Kit outperformed kits tested from other suppliers and ensures high specificity and superior performance in hot-start PCR (see figures " Higher specificity with different primer–template systems" and " Superior performance " and table). The innovative PCR buffer provided with the kit ensures specificity over a wide range of PCR conditions, minimizing the need for optimization (see figure " Tolerance to variable temperatures and magnesium concentrations").

The combination of high specificity and easy handling makes the HotStarTaq Master Mix Kit suitable for use with complex genomic or cDNA templates (see figure " Effect of hot start on RT-PCR performance"), multiple primer pairs (see figure " Specific amplification in multiplex PCR"), and templates isolated from difficult sources or very low-copy targets (see figure " Highly sensitive single-cell PCR"). It is also suitable for projects such as genetic screening, in which large numbers of samples are amplified.


Comparison of hot-start methods
  HotStarTaq DNA Polymerase Hot-start enzyme from Supplier AII Antibody-mediated Manual Wax barrier
Specific amplification ++ + + +/– +/–
Minimal PCR optimization ++ +/– +/–
Easy to use ++ ++ +
HotStarTaq DNA Polymerase specifications

Concentration: 5 units/µl
Recombinant enzyme: Yes
Substrate analogs: dNTP, ddNTP, dUTP, biotin-11-dUTP, DIG-11-dUTP, fluorescent-dNTP/ddNTP
Extension rate: 2–4 kb/min at 72°C
Half-life: 10 min at 97°C ; 60 min at 94°C
Amplification efficiency: ≥105 fold
5'–>3' exonuclease activity: Yes
Extra A addition: Yes
3'–>5' exonuclease activity: No
Contaminating nucleases: No
Contaminating RNases: No
Contaminating proteases: No
Self-priming activity: No >

See figures


HotStarTaq Master Mix is a ready-to-use mixture of HotStarTaq DNA Polymerase, QIAGEN PCR Buffer, and dNTPs. HotStarTaq DNA Polymerase, a modified form of Taq DNA Polymerase, provides high specificity in hot-start PCR.

HotStarTaq DNA Polymerase

HotStarTaq DNA Polymerase is supplied in an inactive state and has no polymerase activity at ambient temperatures. This prevents extension of nonspecifically annealed primers and primer dimers formed at low temperatures during PCR setup and the initial PCR cycle (see figures " Superior performance in hot-start PCR" and " Higher specificity with different primer–template systems"). HotStarTaq DNA Polymerase is activated by a 15-minute incubation at 95°C, which can be incorporated into any existing thermal-cycler program.


QIAGEN PCR Buffer maintains specific amplification in every cycle of PCR by promoting a high ratio of specific-to-nonspecific primer binding during the annealing step in each PCR cycle (see figure " Increased specificity of primer annealing"). Owing to a uniquely balanced combination of KCl and (NH4)2SO4, the buffer provides stringent primer-annealing conditions over a wider range of annealing temperatures and Mg2+ concentrations than conventional PCR buffers. PCR optimization by varying the annealing temperature or the Mg2+ concentration is often minimal or not required (see figure " Tolerance to variable temperatures and magnesium concentrations.").

See figures


HotStarTaq Master Mix Kit is supplied in a convenient master mix format for maximum ease of use. HotStarTaq DNA Polymerase is activated by a 15-minute, 95°C incubation step, which can easily be incorporated into existing thermal cycling programs. Room-temperature reaction setup using the master mix is fast and easy — simply pipet 25 µl HotStarTaq Master Mix into each PCR tube and add 25 µl of primers and template DNA diluted in the RNase-free water provided with the kit (see figure " HotStarTaq procedure"). Pipetting steps are minimized, reducing the possibility of errors and contamination, and ensuring increased throughput and reproducibility. The kit includes a streamlined, optimized protocol for fast and easy PCR setup.
See figures


HotStarTaq Master Mix Kit is highly suitable for a wide variety of applications, including challenging applications such as amplification of: 

  • Complex genomic templates
  • Complex cDNA templates (e.g., RT-PCR)
  • Very low-copy targets (e.g., single-cell PCR)
  • Reactions with multiple primer pairs

Supporting data and figures


ApplicationsPCR, RT-PCR, Complex genomic templates, very low-copy targets
Real-time or endpointEndpoint
Enzyme activity5'-> 3' exonuclease activity
Sample/target typeGenomic DNA and cDNA
Single or multiplexSingle
Reaction typePCR amplification
With/without hotstartWith hotstart


Quick-Start Protocols (1)
User-Developed Protocols (1)
As starting material, 5 g soil was mixed with different amounts of Bacillus subtilis cells. Sensitivity was 5 x 103 cells/5g soil.
Kit Handbooks (1)
HotStarTaq DNA Polymerase; HotStarTaq Master Mix Kit - For highly specific hot-start PCR without optimization  
Brochures & Guides (2)
Addressing critical factors and new solutions
Safety Data Sheets (1)
Certificates of Analysis (1)


Rapid detection of point mutations conferring resistance to fluoroquinolone in gyrA of Helicobacter pylori by allele-specific PCR.
Nishizawa T; Suzuki H; Umezawa A; Muraoka H; Iwasaki E; Masaoka T; Kobayashi I; Hibi T;
J Clin Microbiol; 2006; 45 (2):303-5 2006 Nov 22 PMID:17122023
Quantitative detection of DNA methylation states in minute amounts of DNA from body fluids.
Paliwal A; Vaissière T; Herceg Z;
Methods; 2010; 52 (3):242-7 2010 Apr 1 PMID:20362673
Quantitative PCR-based approach for rapid phage display analysis: a foundation for high throughput vascular proteomic profiling.
Ballard VL; Holm JM; Edelberg JM;
Physiol Genomics; 2006; 26 (3):202-8 2006 May 16 PMID:16705020
Megalin-dependent internalization of cadmium-metallothionein and cytotoxicity in cultured renal proximal tubule cells.
Wolff NA; Abouhamed M; Verroust PJ; Thévenod F;
J Pharmacol Exp Ther; 2006; 318 (2):782-91 2006 May 11 PMID:16690719
Cytochrome P450 gene induction in rats ex vivo assessed by quantitative real-time reverse transcriptase-polymerase chain reaction (TaqMan).
Baldwin SJ; Bramhall JL; Ashby CA; Yue L; Murdock PR; Hood SR; Ayrton AD; Clarke SE;
Drug Metab Dispos; 2006; 34 (6):1063-9 2006 Mar 10 PMID:16531474


What should the starting template DNA quality and quantity be for PCR?

Both the quality and quantity of nucleic acid starting template affect PCR, in particular the sensitivity and efficiency of amplification. PCR sensitivity and efficiency can be reduced by the presence of impurities in nucleic acid preparations or in biological samples. These PCR inhibitors are completely removed when template is prepared using QIAGEN Kits for nucleic acid purification. Please refer to the Brochure "Maximizing PCR and RT-PCR success" for additional information.

The optimal primer–template ratio has to be determined empirically. If too little template is used, primers may not be able to find their complementary sequences. Too much template may lead to an increase in mispriming events. Generally, no more than 1 ug of template DNA should be used per PCR reaction. As an initial guide, spectrophotometric and molar conversion values for different nucleic acid templates are listed below.


Spectrophotometric conversions for nucleic acid templates

1 A260 unit* Concentration (ug/ml)
Double-stranded DNA 50
Single-stranded DNA 33
Single-stranded RNA 40

*Absorbance at 260 nm = 1


Molar conversions for nucleic acid templates

Nucleic Acid Size pmol/ug Molecules/ug
1 kb DNA 1000 bp 1.52 9.1 x 1011
pUC 19 DNA 2686 bp 0.57 3.4 x 1011
pTZ18R DNA 2870 bp 0.54 3.2 x 1011
pBluescript II DNA 2961 bp 0.52 3.1 x 1011
Lambda DNA 48,502 bp 0.03 1.8 x 1010
Average mRNA 1930 nt 1.67 1.0 x 1012
Genomic DNA      
Escherichia coli 4.7 x 106* 3.0 x 10-4 1.8 x 108**
Drosophila melanogaster 1.4 x 108* 1.1 x 10-5 6.6 x 105**
Mus musculus (mouse) 2.7 x 109* 5.7 x 10-7 3.4 x 105**
Homo sapiens (human) 3.3 x 109* 4.7 x 10-7 2.8 x 105**

* Base pairs per haploid genome

** For single-copy genes

FAQ ID -74
What kind of PCR products can be cloned with the QIAGEN PCR Cloning Kit?

PCR products that will be cloned using the QIAGEN PCR Cloning Kit should be generated using a thermostable DNA Polymerase without proofreading activity, such as Taq DNA Polymerase. Such polymerases attach a single A overhang to their reaction products, which can hybridize to the U overhang of the pDrive Cloning Vector. For efficient addition of an A overhang during the PCR procedure, we recommend a final extension step for 10 min at 72°C as described in the standard protocols of the Taq PCR- and HotStarTaq PCR handbook.


FAQ ID -165
Do you have a protocol for polyacrylamide gel analysis of oligonucleotides?
Yes, please follow the Supplementary Protocol 'Polyacrylamide_gel_analysis_of_oligonucleotides' (PCR03).
FAQ ID -961
Is Q-Solution required for PCR with QIAGEN's PCR kits?

Not necessarily. In a lot of cases, the uniquely formulated PCR Buffer provided in the HotStarTag Plus DNA Polymerase, HotStar HiFidelity Polymerase,  Taq DNA Polymerase, HotStarTaq DNA Polymerase, and QIAGEN Multiplex PCR Kits provides optimal amplification of specific PCR products. The usefulness of Q-Solution needs to be determined empirically for each primer/template setup, by running parallel PCR reactions with and without Q-Solution under the same cycling conditions.

Q-Solution changes the melting behavior of DNA and will often improve a suboptimal PCR caused by templates that have a high degree of secondary structure or high GC-contents.  For more details on the effects of Q-Solution on PCR amplification, please see the Q-Solution sections of the HotStarTaq Plus DNA Polymerase, HotStar HiFidelity Polymerase, Taq DNA Polymerase, HotStarTaq DNA Polymerase,  and the QIAGEN Multiplex PCR Handbooks.

FAQ ID -380
Have you tested the effect of inhibitors on PCR performance?

Yes. Please see Table 3 in our brochure Maximizing PCR and RT-PCR success. We tested the effects of different inhibitory substances in a number of PCR systems. We also analyzed the effect of including different volumes of reverse transcription (RT) reaction mixtures in PCR. Please see the table below for a list of commonly encountered template impurities and their inhibitory effects on PCR.


Impurities showing inhibitory effects on PCR

Substance Inhibitory concentration
SDS >0.005% (w/v)
Phenol >0.2% (v/v)
Ethanol >1% (v/v)
Isopropanol >1% (v/v)
Sodium Acetate ≥5 mM
Sodium Chloride ≥25 nM
EDTA ≥0.5 mM
Hemoglobin ≥1 mg/ml
Heparin ≥0.15 i.U./ml
Urea >20 mM
RT reaction mixture ≥15%



FAQ ID -818
How much DNA is obtained in the average PCR reaction?

The DNA yield obtained in a PCR reaction depends on the size of the amplicon, design of the primers, starting amount of template and primers, amplification efficiency, reaction volume, numbers of PCR cycles etc. Therefore it is really difficult to predict what yield to expect. Nevertheless, in our experience, approximately 1 µg is a good guess for most cases.

FAQ ID -750
Can QIAGEN's Taq- and HotstarTaq DNA Polymerases be used for cycle sequencing?
Taq DNA Polymerase and HotStarTaq DNA Polymerase are compatible with cycle sequencing. However, our buffer system is not optimized for this purpose. Optimization of reaction conditions is therefore required when using these Polymerases for cycle sequencing. Unfortunately, we do not have any protocols for this application. An initial activation of the enzyme is necessary if HotStarTaq DNA Polymerase is used.
FAQ ID -741
How can one determine the optimal annealing temperature for a specific PCR assay?

To determine the optimal annealing temperature for a PCR assay, a Temperature Gradient experiment should be performed. To do this, you will set up several PCR reactions in duplicate for the same primer/template combination, using the same PCR chemistry, and subject each of the reactions to a slightly different annealing temperature within a specified range. If a thermal cycler with a temperature gradient function can be used, you can simply program a temperature range for adjacent wells in the cycling block. If no cycler with a gradient function exists in your lab, you will either have to perform duplicate reactions at different temperatures in different machines (if available), or back to back in the same machine.


FAQ ID -288