The PSP test is a qualitative test (yes/no) and should be used as a screen test. There are many different toxin analogues in the PSP family. Each analogue will break at a different level and so the detection limit for the test depends on the specific profile of each sample.
Q: Are the results from the JRT test for PSP similar to that of the mouse bioassay?
The JRT test for PSP can be more sensitive than the mouse bioassay depending on the sample profile. The use of the JRT test for PSP as a screen has reduced the use of the mouse bioassay by more than 90% for some regulatory agencies.
Q: What is the detection limit of the ASP test?
The detection limit of
the Rapid Test for ASP depends on what type of extraction you use.
If you use the Methanol Extraction Method, the tissue concentration in the
extract is 0.2g tissue per mL of extract and the detection limit is
approximately 10ppm.
If you use the Rapid Extraction Method or the mini- AOAC extraction method, the
extract will contain 0.5g tissue per mL of extract and the detection limit is
also around 10ppm.
If you are using the test kits for detecting ASP toxins in phytoplankton, then
the detection limit is around 150ng/mL of ASP toxins per mL of phytoplankton
extract.
Q: Can I make an extract and test for both ASP and PSP?
Yes, both the Rapid Extraction Method and the mini-AOAC Extraction Method can be used on both the Rapid Test for ASP the Rapid Test for PSP. However, the ASP toxin is not stable over time in either of these extracts, and therefore these methods should not be used for ASP if you plan to save and retest the extract later. The PSP toxins are stable over time in these extracts.
RE: SHELLFISH PREPARATION
Q: I have a mixed bucket of clams, oysters and mussels. Can I extract them all together?
No. You must extract only one kind of shellfish for each test. This is because different shellfish have different characteristics of how they take up and metabolize the toxins. For example, mussels are often used as sentinel species in biotoxin monitoring because they take up the toxins very quickly. In contrast, oysters take up the toxin very slowly. Therefore, at a given time in a biotoxin bloom, mussels may be already toxic while oysters may not be toxic yet. Another example is butter clams compared to soft-shell and Manila clams. The butter clams often hold toxicity in their tissues, especially the siphon and other black parts, for days, weeks and even months, while the other types of clams take up the toxin but then metabolize it away quickly when the toxic bloom is over. Because of the differences between the different types of shellfish, it is very important to select and extract only ONE type of shellfish at a time.
Q: Do I have to use 12 animals to make a extract?
It is important that a representative sample of the shellfish be tested. This is because the toxicity is very patchy, and there is much variability between individual animals even in a small area. The representative sample must consist of 12 animals AND 120g of shellfish meat. For example, Pacific oysters can be very large. However, 12 animals must still be homogenized together, even though this is likely to be way more than the 120 g of meat. On the other hand, a hundred tiny mussels may be required to make up the 120g of shellfish meat.
RE: EXTRACTION
Q: What is an extraction? Why do I need a kit to do one?
Extraction is a process whereby seawater or shellfish meat is converted into a liquid containing released toxins (if present). This can be done in three different ways with shellfish and one way with seawater. The extraction kit is a collection of the needed containers, strainers and tools to create the extract and weighs about 2 ½ kg. The items contains in the kit have all been tested and meet the requirements of the process. Most items can be cleaned and re-used, so are one-time purchase.
Q: If I buy my own blender to do the extracts, is the speed of the blender important?
Yes, the speed (rpm) of the blender will determine whether it is able to effectively homogenize shellfish tissue, especially tough tissue like large clams. Our experience indicates that 1800 rpm is not sufficient to homogenize shellfish tissue, while 2000 rpm or more is sufficient. A cordless drill can be used in place of the hand blender, with a hex key and an Oster baby food jar, but the drill must turn at a minimum of 2000 rpm to be effective in homogenizing the shellfish tissue.
Q: Can I buy the components of the extraction kit myself?
We supply the components required to prepare your sample for a Rapid Test largely at cost. There are a number of components that are required in the mini-AOAC kits, as well as a few components of the other kits, that are found in scientific supply catalogues. If you do not have access to these types of catalogues, it may be easier to order the extraction kits from us. If you have access to scientific supplies, we can provide you with a list of components required to prepare your shellfish samples and you can source and purchase these components yourself.
Q: What is the purpose of the buffer used in the Rapid Test?
The buffers used in the Rapid Test kits provide the conditions needed for antibodies in the test strips to perform properly. The conditions of the extracts are not friendly to the performance of biological molecules like antibodies that require physiological levels of salt, pH, protein and other components. The function of the buffer is to change the conditions of the extract to those that are suitable for the antibodies to function optimally. The buffers change the levels of salt, acidity, protein, lipids and other components to those that are optimal for antibody performance.
Q: Can I use any rubbing alcohol and vinegar for the Rapid Extraction Method?
No. You must use rubbing alcohol that contains 70% isopropanol and you must use vinegar that contains 5% acetic acid. This is regular white vinegar and not malt, wine or pickling vinegar.
Q: What concentration of Methanol do I use for the Methanol Extraction Method?
You should use a concentration of 50% methanol to mix with the shellfish homogenate. If you start with 100% methanol, then you should dilute it 1:2 (1 part methanol plus one part water) to produce a final concentration of 50% methanol to be used in the extraction process.
RE: SHIPPING
Q: Why must US customers provide an EIN number
The EIN number (tax number) is the same as the old IRS tax number. This number is required to clear goods into the United States. Shipments without EIN numbers are subject to delays.
Q: What is my shipping address?
The shipping address is the physical address where the shipment can be delivered, the billing address can be different. Most deliveries cannot be made to a Post Office Box. The address must be complete, including any ZIP Code or Postal Code. A contact name and telephone number must also be provided to ensure the shipper has no difficulty getting your kit to you.
Q: Why can't I email my credit card information?
Simply stated, email is not a secure method of communication. Please either fax or call your phone order in.