The Transfection Experts

Our work at Mirus Bio began with a passion for science. That passion continues today with a brand that reflects our commitment to deliver the best results, support, and technologies to scientists worldwide. While our expertise has expanded over the past 25 years, our focus remains the same: We care about transfection as much as you care about your research.

Mirus Bio is a long-standing leader in the field of gene delivery technology. In addition to offering world-class transfection reagents for basic research, we now focus on providing solutions for therapeutic viral vector production, protein production and genome editing.

Our most recent breakthrough product line of TransIT-VirusGEN® Transfection Regents provide superior titers for small-to-large scale production of AAV and lentiviral vectors, supporting gene therapy researchers from discovery to the clinic.

Our History

Mirus Bio’s initial breakthrough came in 1996 with the development of a new type of transfection reagent, TransIT®-LT1, that enabled high-efficiency gene delivery without cytotoxicity. This transfection reagent remains the gold standard for gene delivery applications that particularly require low toxicity.

Taking cues from the mechanisms of naturally occurring and recombinant viruses, Mirus continued to develop and introduce of a wide range of non-viral delivery technologies using blended formulations of proteins, polymers and lipids in conjunction with novel chemistries that provided unique nucleic acid delivery capabilities. Instead of solely focusing on one chemical carrier such as liposomes or cationic polymers, this “biomimetic” approach yielded reagents that were among the most efficient transfection tools available to life science researchers.

Another notable breakthrough came in in 2001, when Mirus Bio scientists introduced the first transfection reagent specifically designed to deliver siRNA with high efficiencies: TransIT-TKO® Transfection Reagent. In 2013, we introduced the TransIT-X2® Dynamic Delivery system which delivers a wide array of cargoes including plasmid DNA, siRNA, miRNA, CRISPR guide RNAs and CRISPR/Cas9 ribonucleoprotein complexes.

With an understanding that some cell types were resistant to chemical transfection, Mirus researchers also developed and introduced the Ingenio® Electroporation Solution which can be used on any conventional device, including our own easy-to-use and cost-effective Ingenio® EZporator® Electroporation System.

Mirus Bio expanded to address the biopharmaceutical research market with the introduction of our CHOgro® High Yield Expression System—a fully optimized expression platform for achieving high protein yields from transient transfection of suspension CHO cells. The CHOgro® High Yield Expression System offers a rapid means for developing protein-based biotherapeutics within a single host cell type with titers that exceed all other commercially available transient expression systems.

While the basic principle of our transfection products was founded on non-viral gene delivery, our scientists next aimed to dramatically improve the production efficiency for viral vectors used in gene and cell therapy. To this end we most recently developed the TransIT-VirusGEN® Transfection Reagent – a workhorse reagent that efficiently delivers AAV and lentivirus packaging vectors to adherent and suspension HEK 293T cell types for high-titer virus production. TransIT-VirusGEN® is also available as TransIT-VirusGEN® SELECT, which is identical in formulation but undergoes testing for identity, sterility, mycoplasma and endotoxin. In 2021 we will release a GMP-grade TransIT-VirusGEN® reagent.

Mirus Bio Solutions for AAV and Lentiviral Vector Production

Mirus Bio Solutions for Protein Production

Mirus Bio Solutions for CRISPR/Cas9 Genome Editing

Mirus Bio Solutions for High Efficiency Electroporation

Mirus Bio Solutions for Broad-Spectrum Transfection

Mirus Bio Solutions for Baculovirus Production


Mirus Bio LLC

5602 Research Park Blvd, Unit 210

Madison, WI 53719


Phone: (608) 4412852

Contact: Miguel Dominguez, Director Sales & Support


  • We show how to evaluate transfection reagents under optimal conditions by testing each reagent side-by-side on the same day with the same batch of cells.

  • HEK 293 cells require proper care for optimal performance in your next experiment, whether it be for basic science research or for production of biotherapeutics.

  • We review a procedure to adapt suspension CHO and 293 cultures, which also serves as a general protocol that has been successful with multiple other cell types and media.

  • We explain how growing CHO cells in suspension will allow for more manageable cell culturing at larger scales and ease in harvesting, which ultimately results in higher yields.

  • Attributes of the new and improved CHOgro High Yield Expression System help researchers obtain gram quantities of protein, simplify workflows, and shorten development pipelines.

  • In this app note, we describe three transfection methods and highlight the Mirus Bio TransIT® transfection reagents and Ingenio® EZporator® Electroporation System.


  • TransIT-VirusGEN® SELECT enhances the delivery of packaging and transfer vector DNA to suspension and adherent HEK 293 cell types to increase production of recombinant lentivirus and AAV. It includes release testing and quality documentation to streamline ancillary material qualification.

  • CHOgro® High Yield Expression System is a cost-effective transient transfection system for high yield protein production in suspension CHO cells. This system features an enhancer that provides rapid, industry-leading protein yields and accomplishes all transfection and enhancer steps in one day.

  • In 1995, Mirus began its journey with the goal of providing the best tools for gene delivery. With over 20 years of experience and multiple breakthroughs in the field of transfection, Mirus is a global leader and trusted brand in nucleic acid delivery. In this short video, you will learn about our transfection products and technologies and how they address the needs of researchers who need turn-key solutions for a wide array of applications that include: virus and protein production, CRISPR, electroporation and stem cells.