Sample Requirements
For DNA samples submitted, Customer is required to ensure the Quality Control (QC) data at the time of sample submission meets the minimum requirements concerning the total amount, concentration, and quality of the DNA submitted. For microbial culture or direct environmental samples submitted, Customer is obligated to ensure that the sample submitted is non-pathogenic to humans and does not contain any substance that may pose a health risk to the personnel working with the samples in our laboratory.
DNA sample
NGS
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Total quantity ≥ 400 ng
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Concentration ≥ 20 ng/µL; Volume ≥ 20 µL
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Purity: A260/280 = 1.8 – 2.0
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Slight deviations are usually fine. QC-failed samples will be considered high-risk ones of which data quality is not guaranteed and will be fully charged even if sequencing fails.
Amplicon project
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No specific requirements on DNA quantity and quality.
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No PCR inhibitors.
Failed samples will be charged at a small fee to cover reagent and labor costs.
Nanopore/PacBio
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Double the quantity and concentration as NGS.
Notes:
(1) The final concentration of each sample will be measured using QUBIT or an equivalent fluorometer after the samples are received. If the samples do not pass QC, We will notify the Customer, and Customer shall either notify us to cancel the failed samples or re-send the samples concerned within ten workdays. Customer can request that the “QC-failed samples” be sequenced, in which case we will prepare the library and sequence the “QC-failed samples” without bearing any responsibility for the data quality. Customer should notify whether plasmid, chondriosome, chloroplast, and other non-bacterial-origin DNA exist in the samples submitted. Customer should notice that, If the DNA originates from a mixture of multiple microbial species, the quality of final assembly and genome annotation will be compromised significantly, and we will not attempt to separate all assemblies into individual species by any means.
(2) An aliquot of DNA sample may be stored temporarily in case of a failed library preparation. All DNA samples will be discarded within 3 months after the project is completed.
Microbial pure culture sample
Agar plates:
colonies should be easily visible and cover > 20% of the surface area on a standard-size petri dish (⌀ 90mm); the agar should not dry out and maintain a good texture for easy collection of cells with a standard sterile loop used in microbiology laboratories.
Pellets:
Bacterial pellets should be placed in a 1.5 mL or 2 mL centrifuge tube. The size of the pellet shall not be less than that generated by centrifuging 2 mL of E. coli cultures grown in LB overnight at 37 °C, typically covering a round area of ⌀3-5 mm.
Notes:
Customer should pay close attention to contamination on agar plates or in bacterial pellets. Customer must ensure each sample submitted is a single pure culture without being mixed with other species. In any case, we will continue the workflow and sequence the genomic DNA extracted from the samples submitted. We will not accept the complaint on the culture’s purity issue filed by Customer based on the genome sequence data generated in this project.
Sample Examples
Pathogens
For shipping of potential pathogens at BSL-2, please always neutralize them first before shipping. The typical working lysis buffer we use to neutralize pathogens is:
Tris-HCl: 10–50 mM, pH 8.0
EDTA: 1–10 mM
NaCl: 50–150 mM (optional but common)
Detergent:
SDS 0.5–1% or
Triton X-100 / NP-40 0.5–1%
Enzymes (not mandatory):
Lysozyme: ~0.5–2 mg/mL (critical for many bacteria; especially Gram+)
Proteinase K: ~0.1–0.2 mg/mL
Only the pellet form of pathogens covered by 200-400 µL lysis buffer is accepted.
Packaging Recommendations
To prevent sample leakage and cross-contamination, customers are highly recommended to use high-quality consumables that can resist external forces and keep the original shape during transportation.
Some inappropriate materials for packaging include 8/12 well PCR strips, 96 well plates with 8/12 well PCR strips cap, 96-well PCR convex plates, 0.2-0.6 mL tubes, and screw-capped centrifuge tubes. Our experience shows that these consumables cannot safely store samples during transport. The strips or caps tend to be loosened or fall off, causing sample leakage, evaporation, cross-contamination or other issues.
We suggest customers only use 1.5 mL or 2 mL centrifuge tubes with a thick wall and 96-well PCR plates manufactured by trustworthy brands. We do not recommend screw-capped tubes as they are incompatible with our automation pipelines. For PCR plates, we recommend using PCR plates with a flat surface that can be evenly sealed.
Please avoid using sticky sealing films on plates that can peel off easily at low temperatures, especially when shipping with dry ice. Heat-sealing for the plate is preferred. For PCR plates with sharp conicals at the base, please safely wrap the plates with bubble wrap for better protection.
Packaging Examples
Sample Labels
All samples must be clearly labelled. Our technical team will photograph each sample vial and confirm the sample IDs with the customer.
A sample sheet is not mandatory; however, providing one can help us identify and process samples more efficiently.
Recommended naming convention: Letter + number (e.g., A1, B12).
Because we often pool large numbers of samples in a single sequencing run, naming conflicts may occur. In such cases, we may assign revised sample IDs by adding letter prefixes to ensure uniqueness.
Shipping Address
Samples should be packed in a proper package and shipped to the following address by express only, not by regular mail or freight, preferably under cold conditions, using foam boxes filled with blue ice packs or dry ice. Avoiding free air space inside the package can extend the cooling period during transportation.
Europe
mBioWorks ApS
Naverland 1C
2600 Glostrup
Denmark
Tel. +45 – 93 99 19 81
E-mail: info@mbioworks.com
Name: Sample Team
Asia
mBioWorks HongKong
M03 RmA, 8/F Excelsior Building
68-76 Sha Tsui Road, Tsuen Wan
Hong Kong
Tel. +852 – 94 01 39 91
E-mail: info@mbioworks.com
Name: Zeng Yong Hui
Free Shipping
For a large project that involves ≥20 samples with standard rates or an order larger than EUR 2,000 during a campaign/promotion, we provide free shipping within the EU and the UK. Please get in touch with us when the samples are ready for shipping and provide detailed package information on size and weight. We will generate a pre-paid UPS label for customers to attach to the package.
Choice of Couriers
For time-sensitive packages that customers wish to arrive at our Copenhagen laboratory within 2 business days, we highly recommend UPS/DHL/Fedex Express. In such cases, GLS/DAO/BRING/PostNord and others that are mostly designed for consumer products are NOT good options.
Customs Clearance
For shipments originating outside the EU, please clearly indicate “DNA test samples” or “Neutralized microbes for research purpose only“ without commercial value on the waybill and on the commercial invoice.
As a best practice, always include a commercial invoice and place it together with the waybill. If the courier is unable to locate this documentation, the shipment may experience significant delays. Providing additional approval or authorization documents from your institution will further facilitate customs clearance.
In general, the more complete and accurate the documentation provided, the faster the customs clearance process will be.
UPS invoice example:
DHL invoice example:
Institute statement example:
