High-quality gRNAs for CRISPR-Cas9 and screening applications

When using the CRISPR-Cas9 system to knock out gene expression or knock in a specific mutation, the design, production, and delivery of high-quality guide RNAs (gRNAs) are critical to success. Whether you need transfection-ready gRNAs to use with TrueCut Cas9 Proteins or you need to harness lentivirus to deliver your editing tools to hard-to-transfect or primary cells, we have you covered. Use our gRNA gene search tool to find predesigned gRNAs in either of these formats, or continue to our selection guide below for other choices.

For functional genomics screening, we’ve also packaged our advanced gRNA designs into CRISPR libraries for high-throughput arrayed screening or economical pooled screening.

Selection guide to CRISPR gRNA formats

 Diagram of TrueGuide Synthetic gRNA
TrueGuide Synthetic gRNA
Diagram of LentiArray Lentiviral gRNA
LentiArray Lentiviral gRNA
Diagram of gRNA molecule
Precision gRNA Synthesis Kit
  • A complete kit to generate ready-to-transfect gRNAs from a DNA template
FormatSynthetic RNA oligo, chemically modified for stabilityLentiviral particlesIn vitro-transcribed (IVT) gRNA
ApplicationKnockout (predesigned) or knock-in (custom)Knockout, including library screeningKnockout or knock-in
  • Human and mouse (predesigned)
  • All other species (custom)
  • Human (predesigned)
  • All other species (custom)
  • All species
Delivery methodLipid-mediated transfection or electroporationLentiviral transductionLipid-mediated transfection or electroporation
Recommended Cas9 formatTrueCut Cas9 ProteinsLentiArray Cas9 LentivirusTrueCut Cas9 Proteins
ControlsPositive and negative controls availablePositive and negative controls available 
 Order nowOrder nowOrder now

Quick tools to search and order gRNAs

Search for predesigned synthetic or lentiviral CRISPR sgRNAs

TrueGuide Synthetic gRNAs are ready-to-transfect CRISPR single guide RNAs (sgRNAs) designed to provide specific and high-efficiency knockout of your target gene. If you need to enrich edited cells, are working with difficult-to-transfect cells, or need long-term sgRNA expression, use our LentiArray CRISPR gRNAs.

Order a custom synthetic gRNA

Have a design of your own? Whether it’s from a journal article, a colleague, or your favorite design tool, use our simple, fast interface to upload the custom gRNA sequences you would like synthesized into a custom TrueGuide gRNA

Use our design tool to create a gene editing experiment and order your gRNAs

Need design assistance for creating an engineered cell line? You can design your CRISPR gene knockout, knock-in, or tagging experiment, and order a complete set of reagents (including gRNAs) for it, with our free TrueDesign Genome Editor software.

Contact us for guide RNAs in plate format or other special orders

To order more than 24 gRNAs for delivery on a 96-well plate, or for gRNAs for use with other nucleases or specific scaffold sequences, please contact us at GEMservices@thermofisher.com.

TrueGuide Synthetic gRNA for CRISPR

Invitrogen TrueGuide Synthetic gRNAs are ready-to-transfect CRISPR guide RNAs designed by a proprietary algorithm for high-efficiency editing. These predesigned, guaranteed single guide RNAs offer targeted knockdown with high specificity across the human and mouse genomes.


TrueGuide 1-piece modified Synthetic gRNA
Predesigned knockouts for mouse and human cells 
Custom sequences 
Validated controls available 
Available in plate format 
Chemical modifications* 
Ideal for primary and stem cells 

*Chemical modifications include 2´O-Methyl analogs and phosphorothioate linkages to increase editing efficiency and protect against nuclease degradation.

Data: High-efficiency editing with TrueGuide Synthetic gRNAs

Bar graph showing the cleavage efficiency of multiple kinase genes using TrueGuide Synthetic gRNAs
Figure 1. Robust cleavage of kinase genes with TrueGuide Synthetic gRNAs in Cas9-expressing ME-180 cells. Average cleavage efficiency was >60%.

Data: TrueGuide Synthetic gRNAs help maintain cell viability

Two bar graphs showing high viability of cells transfected with TrueGuide Synthetic gRNAs
Figure 2. TrueGuide Synthetic gRNAs delivered with optimized protocols cause minimal cell toxicity. Lipofectamine CRISPRMAX was used to complex and deliver TrueCut Cas9 Protein v2 and target-specific TrueGuide Synthetic gRNAs into two cancer cell lines using our recommended transfection protocols. Of the three loci, two (PRKCG-T1 and CMPK1-T1) were known to be challenging to edit. Cell viability was measured using PrestoBlue. Data showed transfection caused minimal toxicity, with overall cell viability maintained at close to 100%. 

TrueGuide Synthetic Guide RNAs—Frequently asked questions (FAQs)

gRNA, or guide RNA, is part of the CRISPR-Cas9 system. The gRNA molecule has two components: a target-specific CRISPR RNA (crRNA) and an auxiliary trans-activating crRNA (tracrRNA). The gRNA guides the Cas9 protein to a specific genomic locus via base pairing between the 20-mer crRNA sequence and the target genomic sequence. 

sgRNA stands for single guide RNA, as opposed to the conventional, native S. pyogenes CRISPR-Cas9 system that uses a two-part guide in which CRISPR RNA (crRNA) is hybridized with a tracrRNA. An sgRNA combines both RNAs into a single, long RNA. sgRNAs are typically 100 nt in length and can be expressed from a vector or chemically synthesized.

Because the modified sgRNA demonstrates superior efficiency across more cell types than the two-part system, the TrueGuide crRNA:tracrRNA two-part guide RNA product format has been discontinued. This has allowed us to simplify our synthetic gRNA offering and focus on the modified sgRNA.

CRISPR gRNAs are available from Thermo Fisher Scientific as chemically synthesized RNA oligos, packaged lentiviral particles, or generated as in vitro transcribed (IVT) gRNAs using the GeneArt Precision gRNA Synthesis Kit.

Chemical modifications include 2’ O-Methyl analogs and phosphorothioate internucleotide linkages at the 5′ and 3′ ends of the molecule. These modifications enhance editing efficiency by increasing binding to the target site and inhibiting nuclease degradation, respectively.

You can purchase an sgRNA without any chemical modifications by using the custom gRNA order tool.

TrueGuide Synthetic gRNA, when transfected with TrueCut Cas9 Protein, offers maximum editing efficiency across broad cell types while minimizing cell toxicity and innate immune responses. Unlike a plasmid-based system, the RNP system is transient with faster turnover, which minimizes random integrations and off-target effects.

TrueGuide Synthetic gRNA sequences are analyzed by mass spectrometry to verify sequence integrity.

To estimate CRISPR/Cas9 mediated editing efficiency in a pooled cell population, you can use the GeneArt Genomic Cleavage Detection Kit, next-generation sequencing (NGS), or Sanger sequencing. Either sequencing method—NGS of the amplicons from edited populations, or Sanger sequencing of amplicons cloned into plasmids—gives a more accurate estimate of percent editing efficiency and indel types. See the TALEN and CRISPR Validation Tools page for a more extensive discussion of these methods, and the TrueGuide Synthetic gRNA User Guide for protocol guidance.

LentiArray lentiviral gRNA for screening and editing hard-to-transfect cell lines

Invitrogen LentiArray CRISPR gRNA are pre-designed, pre-packaged gRNA lentiviruses designed for efficient gene knockout. LentiArray CRISPR gRNA designs have been created with a proprietary gRNA design algorithm and are optimized for maximum knockout efficiency without compromising specificity. 

LentiArray CRISPR gRNAs are available to support pre-screen assay development and post-screen hit validation when performing high-throughput screening experiments with the LentiArray CRISPR libraries. LentiArray CRISPR gRNA should be used with LentiArray Cas9 Lentivirus to perform genome editing experiments in hard-to-transfect cell lines and primary cells.

Data: Successful knockout of EGFP with LentiArray gRNA

Knockout of EGFR expression with LentiArray gRNA shown via analysis of immunofluorescence is stained cells as well as western blot analysis

Figure 3. CRISPR-Cas9-mediated knockout of EGFP with LentiArray gRNA.(A) A431 cells were subjected to EGFR knockout (right column) using LentiArray Cas9 Lentivirus and LentiArray CRISPR gRNA and compared with untreated cells (wild type, left column) and cells treated with Cas9 but no gRNA (Cas9 control, middle column). Cells were stained for EGFR expression (green), nuclei (blue), and cytoskeletal F-actin (red), and analyzed for immunofluorescence. Loss of EGFR expression was observed only in EGFR knockout cells (c, f). (B) Reduction of EGFR signal was also observed via western blot for target protein in EGFR knockout cells vs controls.

IVT gRNA for rapid generation of custom designs

The GeneArt Precision gRNA Synthesis Kit is a complete system for rapid synthesis of guide RNA (gRNA). 

With this kit, two short single-stranded oligos that code for the target sequence serve as the starting material, and the gRNA template is assembled from these oligos with a T7 promoter in a short “one-pot” PCR reaction. Following this, the assembled product is then used as template in an in vitro transcription (IVT) reaction. A subsequent rapid purification step produces high-yield (>10 µg), high-concentration (>200 ng/µL), transfection-ready gRNA in as little as four hours.

Combining IVT gRNA with our TrueCut Cas9 Protein v2 has been tested in a variety of suspension and adherent cell lines with >70% cleavage efficiencies and no indications of toxicity. 

The resulting gRNA can also be co-transfected with our ready-to-transfect CRISPR Nuclease mRNA. Both protein and mRNA Cas9 formats require no plasmid manipulation and are compatible with high-throughput and multiplex genome-wide cell engineering approaches.

Order the IVT gRNA synthesis kit

For Research Use Only. Not for use in diagnostic procedures.

Stylesheet for Classic Wide Template adjustments