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TransIT-TKO Transfection Reagent – 0.4 mL

A high efficiency, low toxicity, siRNA and plasmid DNA transfection reagent for mammalian cells



  • Broad Spectrum siRNA and Plasmid DNA Delivery – Utilize one transfection reagent and protocol for a wide variety of cells
  • Low Cellular Toxicity – Maintain cell density and reduce experimental biases
  • Reproducible Results – Obtain consistent, targeted gene knockdowns from day to day
  • High Knockdown Efficiency – Achieve optimal gene silencing in a large percentage of cells to ensure experimental success

SKU: MIR 2154

Supporting Data


High Efficiency Endogenous Knockdown in iCell® Cardiomyocytes. The TransIT-TKO® Transfection Reagent was used to transfect iCell® Cardiomyocytes (Cellular Dynamics International) plated at a density of 136,500 cells per well of a 12-well plate pre-coated with fibronectin. Seven days post-plating triplicate wells were transfected with TransIT-TKO® (3-5 µl per well) and non-targeting control siRNA or GAPDH targeting siRNA (50nM per well). Seventy-two hours post-transfection, the amount of GAPDH mRNA was measured relative to 18s rRNA mRNA levels using qRT-PCR and then scaled to the expression level of the non-targeting control siRNA.  Error bars represent the standard error of the mean (SEM) of three independent complexes. See more information on stem cell applications.


Delivery of Fluorescently-Labeled siRNA Using TransIT-TKO® Transfection Reagent. HeLa (70% confluence) cells in 12-well plates were transfected with TransIT-TKO® Transfection Reagent (3 μl/well) and Label IT® siRNA Tracker™ Fluorescein-labeled siRNA duplexes (GREEN, 50 nM final concentration in the well). The cells were incubated 24 hours post-transfection then fixed and counterstained with TO-PRO®-3 (nuclei, BLUE) (Life Technologies) and Alexa Fluor® 546 Phalloidin (actin, RED) (Life Technologies). Confocal images were acquired on a Zeiss LSM 510 Confocal Microscope.


High Efficiency Knockdown and Low Toxicity Using TransIT-TKO® Reagent in HeLa Cells. Firefly and sea pansy luciferase reporter vectors were co-transfected into HeLa cells using TransIT®-LT1 Reagent. Cells were incubated for at least 4 hours, split into 24-well plates, allowed to adhere and transfected with 25 nM of either a non-targeting siRNA or an anti-firefly luciferase siRNA using the indicated reagents with the volumes noted beneath each well. Luciferase expression, normalized to non-targeting siRNA control (bar graph) and lactate dehydrogenase (LDH) levels (line graph) were measured at 24 hours post-transfection. LDH levels are reported as % cytotoxicity compared to cells alone and were measured using a commercially available colorimetric assay; all values at or below zero are represented as zero on graph.


Efficient Knockdown of Endogenous Genes in Primary Hepatocytes Using TransIT-TKO® Reagent. Primary mouse hepatocytes were transfected with the indicated siRNAs or a non-targeting control siRNA using the TransIT-TKO® Reagent. Twenty-four hours post-transfection, the amount of each mRNA was measured relative to GAPDH mRNA levels using qRT-PCR and then scaled to the expression level of the specific target mRNA in the cells alone (untreated) controls.


Cell Line (Source) Endogenous Transcript Knockdown Efficiency
BNL CL.2 (mouse liver) MAPK1 80%
MAPK3 83%
HeLa (human cervix) Lamin A/C 80%
Hepa1c1c7 (mouse liver) MAPK1 80%
MAPK3 75%
MEK1 75%
PTEN 80%
HepG2 (human liver) MAPK1 80%
NIH 3T3-L1 MAPK1 70%
MAPK3 70%
Secondary Human Astrocytes Lamin A/C 80%
Primary Mouse Hepatocytes ABC A1 70%
Lamin A/C 81%

Knockdown of Endogenous Genes Using TransIT-TKO® Reagent. Various cells were transfected with siRNAs targeting the indicated genes using the TransIT-TKO® Reagent, and the knockdown percentage was determined using quantitative RT-PCR.



Storage Conditions
All Configurations: Store at 4°C

Product Guarantee
All Configurations: 1 year

Usage Statement
All Configurations: For Research Use Only.

Animal Origin Statement
All Configurations: This product is animal origin free.

Technical Product Literature

Full Protocol
TransIT-TKO® Full Transfection Protocol (PDF)

Quick Reference Protocol
TransIT-TKO® Quick Ref Proocol (PDF)


Additional Resources

Technical Report: High Efficiency siRNA Delivery In Vitro (PDF)
Publication: Delivery of small interfering RNA to mammalian cells in culture

Stem Cell Applications
Optimized transfection protocol for iCell® Cardiomyocytes (Cellular Dynamics International) using TransIT-TKO® Transfection Reagent: PROTOCOL (PDF) | iCell® Page
Cell Types successfully transfected at Mirus using TransIT-TKO® Transfection Reagent (PDF)


See the TransIT-TKO FAQs

Using transfection reagents and enhancers from Mirus has given our platform a competitive advantage. Increasing efficiency and lowering costs for all of our porgrams.


Sally Mader, PhD
ZYZ Theraputics