Lipofectamine RNAiMAX Reagent kit box and one tube with a blue cap

Get superior transfection for gene knockdown studies with our best siRNA transfection reagent

Invitrogen Lipofectamine RNAiMAX Transfection Reagent, our best siRNA transfection reagent, offers an advanced, efficient solution for siRNA delivery. No other siRNA-specific transfection reagent provides such easy and efficient siRNA delivery in a wide variety of cell lines. You can achieve the highest transfection efficiencies in cell lines including the common cell types, stem cells and primary cells, as well as traditionally hard-to-transfect cell types.

  • Unmatched performance, delivering greater knockdown with less siRNA
  • Easy optimization with a simple protocol helps ensure great performance

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With greater knockdown at lower siRNA concentrations, Lipofectamine RNAiMAX outperforms other reagents

When it comes to achieving effective gene knockdown, Lipofectamine RNAiMAX Transfection Reagent outperforms other siRNA transfection reagents. High knockdown levels of target genes can be achieved with as little as 1 nM siRNA (Figure 1). The Lipofectamine RNAiMAX protocol recommends using 10 nM siRNA as a starting point to maximize knockdown levels. Even when coupled with low concentrations of siRNA, RNAiMAX reagent helps obtain high knockdown levels while is also beneficial in minimizing background expression from untransfected cells and to minimize other non-specific effects.

Bar graph showing the effects of different transfection reagents on p53 expression levels in cells transfected with either a scrambled control or p53 siRNA

Figure 1. Superior knockdown with Lipofectamine RNAiMAX Transfection Reagent compared to competing siRNA transfection reagents. At both 10 nM and 1 nM p53 siRNA, Lipofectamine RNAiMAX Transfection Reagent provides more effective knockdown relative to non-transfected cells than other RNAi reagents, including siLentFect™ (Bio-Rad), DharmaFECT™ (Dharmacon), and HiPerFect (Qiagen) reagents.

Lipofectamine RNAiMAX exhibits minimal transfection-mediated cytotoxicity

Transfection-mediated cytotoxicity can mask the true phenotype of a target gene being studied, so minimizing the amount of reagent used in your transfections is a critical factor for successful RNAi experiments.

Lipofectamine RNAiMAX Transfection Reagent gives maximal knockdown and excellent cell viability across a 10-fold concentration range of the reagent (Figure 2). This broad peak of optimal transfection activity with minimal cytotoxicity means you can be assured of achieving high knockdown levels despite differences in cell density, minor experimental inaccuracies, and other variations. Not also does this make it easy to optimize Lipofectamine RNAiMAX reagent for the lowest siRNA concentration but also reduces cellular stress and cytotoxicity in your experimental system simultaneously.

Bar graph showing the optimal knockdown and minimal cytotoxicity in A549 cells transfected with Lipofectamine RNAiMAX Transfection Reagent

Figure 2. Optimal knockdown and minimal cytotoxicity in A549 cells transfected with Lipofectamine RNAiMAX Transfection Reagent. A range of 0.1 μL to 1.0 μL of Lipofectamine RNAiMAX reagent was used, resulting in efficient knockdown of the p53 gene expression level while maintaining excellent cell viability.

RNAiMAX offers a simple protocol for easy optimization in a broad spectrum of cell lines

Lipofectamine RNAiMAX offers a simple protocol to achieve high transfection efficiencies in many cell types. There is no need to remove Lipofectamine-siRNA complexes, or change or add cell culture media following transfection.

When combined with Invitrogen BLOCK-iT Alexa Fluor Red Fluorescent Control, Lipofectamine RNAiMAX reagent gives you the most versatile approach to all your knockdown experiments (Table 1, Figure 3). Spend less hands-on time and get better results faster.

Two microscopy images, one in fluorescence which HeLa cells are transfected with Invitrogen BLOCK-iT Alexa Fluor Red Fluorescent Control using RNAiMAX reagent and bright-field image 24 hr after transfection.

Figure 3. Improve your transfection efficiencies using the BLOCK-iT Alexa Fluor Red Fluorescent Control. (A) HeLa cells were transfected with the BLOCK-iT Alexa Fluor Red Fluorescent Control (50 nM) using Lipofectamine RNAiMAX Transfection Reagent. (B) 24 hours post-transfection, nearly 100% of the cells take up the control and retain a normal morphology, as seen in the bright-field image.

Table 1. Cell types successfully transfected with siRNA and Lipofectamine RNAiMAX Transfection Reagent

Cell line/typeCell type
MDA-MB-435Breast cancer
HeLaCervical carcinoma
HT1080Human fibrosarcoma
A549Lung carcinoma
HepG2Liver carcinoma
MCF7Breast cancer
Mesenchymal stem cellsBone marrow
HAMSCHuman aortic smooth muscle cells
HEKaHuman epidermal keratinocytes
HREHuman renal epithelial cells
NTERA-2Embryonal carcinoma cells
HUVECHuman umbilical vein endothelial cells
ADSCAdipose-derived stem cells
HCT116Colon carcinoma

How to perform an siRNA transfection with Lipofectamine RNAiMAX

Follow this step-by-step video to perform a successful siRNA transfection using Lipofectamine RNAiMAX reagent.

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Our Lipofectamine reagent-specific protocols have been optimized for efficiency, viability, and reproducibility across a broad range of cell types. Search this library to find protocols and citations curated to fit your experimental needs. Filter by cell type, payload, and product of choice to easily unlock your answers.

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