Frequently Asked Questions
Often we receive questions from our customers. Therefore, we decided to answer the most common questions here.
If you still do not manage to find an answer to your question, please do not hesitate to contact us.
How should allergens be stored?
How should I store the products after I dissolved them with a PBS buffer?
We do not recommend to store the solution with PBS at -20ºC. By using PBS as a buffer and storing at -20ºC you will create phosphate acid and phosphate acid can damage the proteins. If you are going to use PBS buffer, you can store it in a refrigerator at 2-8ºC. The time you can store it depends on the quality of your PBS and how sterile you are working. If you really want to freeze the solution we recommend to use 0.9% NaCl. In general, we recommend to freeze-thaw your material as little as possible. Find out more here.
How can I order your products?
At what temperature do you ship your products
What is the difference between a whole culture and mite bodies?
Freeze dried mite bodies (.30) consists only, at least for 95%, of mite bodies (ratio Der p 1/Der p 2 is 1:1). Downstream processing of mite bodies results in a freeze dried product which has higher Der p 1 and Der p 2 concentrations than mite bodies (.30).
In conclusion, it is simply a question of quantities and ratios of Der p 1/Der p 2 in Whole cultures (.60) and mite bodies (.30).
I am using your biotinylated HDM products. Do you have a protocol for the use of these biotinylated products?
What kind of medium do you use in producing your mite cultures which give the mite allergens?
Can I re-order material from a specific LOT/ batch?
Can you deliver excrements of the house dust mites?
Why is it important to work with purified allergens rather than allergen extracts?
What is the difference between the forms you offer?
.30: Mite bodies: purified mite bodies, this does not contain other material such as the faeces of the mites. Delivered in total dry weight.
.40: Semi-purified mite bodies: semi-purified mite bodies. Less purified then the .30. Delivered in total dry weight.
.60: Whole culture: A whole culture consist of all the material of the house dust mite cultivation. This means: mite bodies, eggs, larves, cultivation medium and the faeces. Delivered in total dry weight.
.64: Extract with low level of endotoxin: the same as our regular .85 extract but with a low level of endotoxin. Delivered in total dry weight. We only have this product available of the D. pteronyssinus mite.
.71: purified Group 1 allergen (Der p 1 or Der f 1). Based on protein content (BCA).
.72: purified Group 2 allergen (Der p 2 or Der f 2). Based on protein content (BCA).
.85: Extract (of whole culture): the whole culture which is extracted. A whole culture consist of all the materials of the cultivation, including bodies, eggs, larvae, skin parts, cultivation medium and the excrements. This is the regular extract which is the most used by researchers. Delivered in total dry weight.
.86: Extract (of mite bodies): purified mite bodies which is extracted, this does not contain other material such as the faeces of the mites. Delivered in total dry weight.
.87: Excrements: the purified excrements (faeces/ droppings) of the house dust mites. We have excrement extracts available from D. farinae and D. pteronyssinus. Delivered in total dry weight.
.95: Extract: Regular HDM extract but not filled out on dry weight but on protein content (BCA). These are small vials which are developed for researchers.
In what form do you deliver your products?
How long can I store your products?
Do you ship the products worldwide?
Can we use your raw materials as an active pharmaceutical ingredient (API) starting materials?
I am working with animal models. Do you have examples of models in which house dust mites (HDMs) are used?
What buffer should I use to dissolve the products?
What production process do you have for your moulds?
Are your products suitable for in-humans use and immunotherapy?
How are allergens purified?
How to dissolve mould extracts
Are the products dialysed before freeze-drying?
Our products will be delivered in freeze-dried (lyophilised) form. Before freeze drying the products are dialysed in a volatile buffer. This results in salt free end product. You can dissolve the product in a buffer of your choice.
HDM extracts are made from natural animal material which opens up the possibility for different kinds of bacteria to be present in them from the mite of origin. Autoclaving is not possible with mite extracts as this negatively impact the product and although filtering over a 0,22μm filter does diminish bacterial and fungal contamination it does nothing against one bacterial genus called Mycoplasma.
Endotoxin, also referred to as Lipopolysacharides (LPS), is the major component of the outer membrane of Gram-negative bacteria and is released upon disintegration of the intact bacteria (Gorbet et al, 2004). This can occur either through growth, division, cell death,...
In short: Buffers using phosphates, such as the commonly used phosphate buffered saline (PBS), are frequently used in biochemical research. When your intentions is to freeze a product for long-term storage, we advise against using a phosphate buffer but suggest using...