Custom Plasmids Design, Construction & Preparation Services

Gene synthesis services

OBIO offers gene synthesis services at prices as low as $0.14/bp.

Vector Cloning services

Multiple vector backbones are available.

We offer highly reliable vector cloning services across various backbones. Whether you need CRISPR Cas9 plasmid vector cloning for gene editing, shRNA knockdown vectors for gene silencing, or specialized lentiviral plasmid preparation, our team delivers sequence-verified vectors tailored to your specifications.

*The cloning turnaround refers to the time from production initiation to completion.

It does not include transit time and QC of customer-supplied materials and transit time.

Plasmid preps and scales

To meet the diverse research and application needs, we offer a variety of plasmid extraction services.

* maxiprep(lib): Library plasmid extraction service.

* midiprep and maxiprep use endotoxin-free process for preparation.

*For further discussion of your specific needs or to learn more about our plasmid extraction services or plasmid preparation service, please contact with us.

FAQs of Plasmids

Do you offer downstream virus packaging after plasmid construction service?

Absolutely. As a one-stop AAV and lentivirus manufacturing CRO, we seamlessly transition your custom-cloned plasmids into high-titer recombinant virus production.

What is the typical turnaround time for gene synthesis?

The turnaround time for gene synthesis is generally limited by gene length. Genes shorter than 3,000 bp without complex or repetitive motifs can typically be synthesized within 1 to 2 weeks. For constructs exceeding 3,000 bp, or those containing repetitive sequences or high GC content, the production cycle will be extended accordingly, and the exact lead time shall be assessed on a case-by-case basis.

Do you charge extra for complex sequences (e.g., high GC content, repetitive regions, or toxic genes)?

Our pricing is calculated based on gene length. No extra charges will be applied for sequences with high GC content or repetitive elements; however, synthesis lead time will be prolonged due to inherent technical difficulties of such sequences. Similarly, toxic genes incur no additional fees, and we employ proprietary vectors to clone these genes to facilitate subsequent protein expression and viral packaging.

The footnote says midiprep and maxiprep use "endotoxin-free process." Why does this matter? Is miniprep not endotoxin-free?

All our plasmid prep kits are designed to reduce endotoxin levels. Endotoxins (LPS) from bacteria can activate immune cells and interfere with transfection in sensitive cell types such as primary neurons, dendritic cells, or stem cells. While no kit can completely eliminate endotoxins, our plasmid preps undergo rigorous testing, and each batch of kits is quality-checked to ensure low endotoxin content.

How do I determine whether lentiviral delivery is appropriate for my cell type?

The choice depends primarily on your cell type, transfection efficiency, and experimental objectives. 

High transfection efficiency (>70%): A plasmid-based expression vector is often sufficient for transient expression studies.

Stable cell line generation: A lentiviral vector is generally the preferred choice because it enables stable genomic integration and long-term transgene expression.

Low transfection efficiency (<30%): Lentiviral vectors are recommended, as they can efficiently deliver genes into many difficult-to-transfect cell types.

Moderate transfection efficiency (40–60%): Both plasmid and lentiviral vectors may be suitable. However, lentiviral vectors typically provide more uniform and reliable gene expression.

Unknown transfection efficiency: Lentiviral vectors are often the safer option, particularly for primary cells, stem cells, suspension cells, and other challenging cell types.

If you are unsure which approach is best for your experiment, our technical support team can help evaluate your cell type and application requirements to recommend the most appropriate delivery strategy.