Hyaluronic acid (also called HA or Hyaluronan) is a glycosaminoglycan with elevated viscosity, enabling tissues (eye, skin, joint and synovial fluid…) to resist to physical and mechanical constraints (torsion, flexion…). Over time, when HA production declines, tissues progressively lose these tensile properties, leading to wrinkles and fold, weak re-epithelisation and age-related troubles. But HA is also involved in many other chronic and cancer-related diseases. In this post, we’ll review one of the most popular HA quantification assays (ELISA test), known to be highly sensitive and robust, appreciated by researchers involved in cosmetology and drug discovery. [Read more…]
Gel Filtration – Which column to choose for your size exclusion purification?
Gel filtration (GF), also referred as Size Exclusion Chromatography (SEC), plays a key role in the high quality purification of enzymes, polysaccharides, nucleic acids, proteins and other biological macromolecules. Gel filtration is the simplest and mildest of all chromatography techniques to separate biomolecules on the basis of difference in size. Nevertheless, the list of available columns is quite awesome and the characteristics of each of them are very different. Also, each characteristic highly influences the quality of the final purified product with important consequences in downstream applications.
I’ve put together a simple guide to help you find your GF system, together with some tips and tricks based on my experience when producing recombinant proteins and antibodies for our clients involved in the early R&D stages through to the latest phases of the bio-production flow.
Download your copy of the guide “Gel Filtration – which column should you choose for your size exclusion purification?“
If you have any questions or if you need some help, leave a message below to get in touch with our lab experts!
3 tips for IHC troubleshooting
The sensitivity and specificity of the primary and secondary antibodies used together with the IHC procedure used, are critical to avoid biased results. Several factors can cause false-positive or false-negative data, so they should all be verified as much as possible for each experimental set-up.
3 main experimental stages particularly need to be under control:
- Detection of the antigen of interest by the primary antibody
- Detection of the primary antibody by secondary antibodies
- Tissue preparation
Here, let’s look at 3 tips that will be of help to improve your IHC data. [Read more…]
Antibody purification troubleshooting tips
Antibody-based techniques are widely used in Life Science laboratories. Antibody purification is often required to raise purity yield of antibody production batches or to reach publication-grade data. In this post, take advantage of some technical tips and troubleshooting points to improve your antibody purification.
Why will mixed mode resins revolutionise R&D scale mAb production?
Monoclonal antibody (mAb) engineering and their development as therapeutic or diagnostic tools have become the must in pharmaceutical industry, in medical biotech and in the research world. Purification of this type of biosimilar requires a particular know-how.
What the datasheet of an antibody really means
Today, I’d like to give some tips & tricks on how to select an antibody… by reading its datasheet.
Obvious as it may seem, the datasheet is in fact contractual. It states the characteristics and guaranteed performance of a given product in general, or an antibody in particular. So it should be read carefully before taking a purchasing decision. No matter if you saw a great antibody detecting protein X in polar bear in some publication. If polar bear is not one of the validated species in the datasheet, the antibody is not guaranteed and you won’t get a replacement or refund. [Read more…]
Following your proteins – anti-tag antibodies (I)
When producing recombinant proteins, one can follow the purification process either by antibodies detecting the target protein specifically, or by adding a tag to it, thus using antibodies detecting not the protein itself, but the tag. This allows to have a battery of anti-tag antibodies that can be used with any protein, rather than having dozens of protein-specific antibodies. Our experts in recombinant protein production (either E. coli or HEK293) at our laboratories in France, are well aware of the key points in any of these processes.
It is not so straightforward to design an anti-tag antibody. One must be sure that it is able to recognise the tag, no matter what protein it is attached to. Here, peptide design and validation with multiple recombinant proteins having the same tag (either in the N-t or the C-t) is crucial. The reason why the anti-tag antibodies we have chosen perform so well in the hands of hundreds of researchers across Europe, is because we select them from sources that really follow this rule when producing their anti-tag antibodies. [Read more…]
Which bacterial strains for recombinant protein expression?
Because of their rapid growth and their affordability, bacterial expression systems are very convenient when producing recombinant proteins.
Nevertheless, one of the key elements in the design of the experimental procedures for producing a recombinant protein in E. Coli is the selection of the right bacterial strain for the right protein. This is not an easy step but remains of utmost importance.
Based on our in-house experience, we’ve compiled a guide aimed at helping you in your choice of the “ideal” engineered bacterial strain for efficient recombinant proteins expression.
You’ll find useful information for selecting the reliable strains suited to your downstream applications, with characteristics (quality, biological activity, folding…).
Interested? Download your copy here:
Guide to choosing the best bacterial strains for recombinant protein expression
Clear best-quality in IP/WB data – TrueBlot technology
Immuno-precipitation & Western Blots often suffer from heavy/light chain blotting, contamination, and ongoing interferences. This can prevent obtaining biologically-relevant data in a given experimental model, especially when the target of interest has a size similar to the IgG molecules that may remain. Getting rid of these “artificial” bands can be tricky. In this post, we’ll be taking a look at the robustness of the TrueBlot® products for facing these issues.
8 criteria for selecting your ELISA kits
Biomarkers specialists are often asked to select an ELISA kit for researchers: with thousands of ELISA references available on the market, the choice can be tricky regarding proteins for which several kits available.
When researchers have to choose a new ELISA kit, the price is regularly the first parameter of selection. But my experience with long term projects shows that it should in fact be the very last one…