Quick List

Service Terms
Confidentiality
Delivery
Request to the Customers
Why SinoBio
How to Order
Introduction

    Structural and functional proteomics requires large amounts of very pure and correctly folded protein. Due to simplicity, low cost, and potential to express large quantities of target protein, E. coli expression systems are frequently used. However, production of foreign proteins in E. coli may result in the formation of inclusion bodies. Although inclusion body formation is typically not desirable, the aggregates are resistant to proteolysis, easily purified, and can be denatured with chaotropes. Unfortunately, defining conditions that promote refolding of the target protein into its native conformation is empirical and difficult.
    SinoBio's Protein Refolding Services can help to determine optimal protein refolding conditions by a systematic evaluation of different buffers covering a range of pH and different salt, cyclodextrin, redox agent, and refolding additive concentrations. Associated by the customers we can give a optimized refolding method for the particular protein at last.


Service Terms
  
    Our typical turnaround time is two weeks. SinoBio can provide 20-80% soluble refolded protein at purity of 85% or greater. The final output is dependent on the total amount of target protein comprising the aggregates. The refolded protein is delivered in customized buffer. The major elements of our protein refolding services include the following procedures:

  1. A systemic screen of different parameters including the following:
    1. Direct dilution
    2. Dialysis and diafiltration
    3. Small molecular assistants:
      • Denaturant
      • Amino acids
      • Polymers: micellar and liposomal
      • Alcohol
      • Reducing/oxidizing reagents
      • Salts: Na/K/Mg/Ca and (NH4)2SO4
      • Saccharides: glucose, sucrose, and trehalose
    4. Artificial chaperones: detergent and non-detergent
    5. Matrix-assisted methods: SEC (size exclusion chromatography), HIC (hydrophobic interaction chromatography), affinity column and IEC (ion exchange chromatography)
    6. Gradient methods: pH, Tem, hydrostatic pressure, and denaturant
  2. BUFFER SCREEN: Inclusion body solutions will be dilute to 20 different refolding buffers to determine which parameters will affect the refolding results.
  3. FUNCTION ASSAY I: Refolded protein will applied for functional assayed buy the customer or SinoBio to further confirm refolding effect.
  4. DENATURANT REMOVE SCREEN: An optimized refolding buffer will selected for further refolding assay. Five different techniques are employed to exchange the denaturant buffer with the refolding buffer including dilution, dialysis, diafiltration, gel filtration and immobilization on a solid support.
  5. FUNCTION ASSAY II: Refolding results will be detected by SDS-PAGE, HPLC and/or function assay.
  6. TECHNIQUE TRANSFER: After confirmed by the customer the optimized process will transfer to the customer.
  7. OR, CONTRACT MANUFACTURE: SinoBio also provide contract manufacture for large scale refolding and protein purification service.


Confidentiality
    Your confidential sequence to us by mail will be covered. We will sign non-disclosure or confidentiality agreements when necessary.
    A general template for MTA and CFA are available and you may change the terms according to your requirements and discuss it with SinoBio.


Delivery
    For protein refolding services, we need helps from customers for function assay to determine which is the best refolding condition. Materials delivered to customers include the following:
    1. Samples after buffer screen (analysis results required).
    2. Samples after denaturant remove screen (analysis results required).
    3. Optimized refolding process reports.
    4. Final products after refolding if contract manufacture are required.
    Delivery time:
    The typical turnaround time is 10 business days. Time for shipment is about 4 business days. This may vary depending on where the customer located and accidentally, delayed by custom check.
    The final products will be shipped via fedex. DHL is optional according to the customer's requirements.


Request to the Customers

    1. Protein refolding service can begin from inclusion body or even a electronic protein sequence:
            inclusion body or it's solution
            expressed cell pellets
            expression strain 
            expression plasmid
            cDNA or just a electronic sequence.
    2. Sequence information or detailed protein properties include the pI, hydrophobic property, MW...
    3. SinoBio Biotech can provide some of function assay or customer should transfer the function assay to SinoBio or help us to detect the protein biological activities.

Correlative Service
    Gene Synthesis
    Polyclonal Antibody Production
    Protein Analysis(HPLC, LAL, AA Sequencing, MS, MS/MS)
    Protein PEGylation
    Protein Refolding
    Activity assay for some of the proteins
    Expression in P.Pichia
    Expression in Insect Cells
    Expression in Mammalian Cells
    Expression in e.coli

Why SinoBio
    Professional: SinoBio Biotech focus on recombinant protein manufacture only, and the focus makes us more professional. All of the group leaders are come from big biopharmaceuticals with more than 10 years experience on protein production. The company are well equipped with Bioengenering fermentor, AKATA, HPLC and we can provide cGMP standard for your production. The fermentation scale is from liters to 500 liters. Final production is scale from milligram to tens of gram.
    Expertise: SinoBio's protein experts have more than 300 different protein purification experience, involved in NINE biologics development, most of them are in market and some of them in clinical trails. They also developed about 40 qualified cytokines and tens of biological enzymes.
    Quality: Diverse quality control method available for your choice such as amino acid sequencing, MS, MS/MS, LAL test, HPLC in addition to conventional SDS-PAGE analysis.
    Speed: Fast turnaround time (~10 days for a basic order)
    Price: Competitive prices as low as 800$
    Confidentiality: Strictly confidential customer's data. SinoBio will sign non-disclosure or confidentiality agreements when needed.


How to order
    Please download the order form to specify your information, billing information, and project information;
    Please email the completed order form to info@sinobio.net

    Please follow these instructions closely to speed up your ordering process.

    1. SinoBio Biotech adopt a non-disclosure policy to all of our customers. To protect your proprietary information please mail, email (info@sinobio.net) or fax (+8621-5079-8029) your confidentiality agreement to us for sign. If intended, this should be done before any information is released to us. If you don't have your own NDA/confidentiality agreement, you can find ours at here. Feel free to modify it to suit your specific needs.

    2. Call us (+8621-5079-8029) or email us info@sinobio.net, your gene/protein sequence and particular manipulations you wish us to perform. Particularly give clear instructions on the following options: codon optimization vs. no optimization; host organisms; single host vs. multiple host optimization. Total amount of final protein you required, the qualities and QC terms you required.