Toxins & Reference Standards
Choosing the Right Toxin Preparation
Research-grade bacterial and plant toxins supplied as native, recombinant, toxoid and biotinylated preparations, in purity grades from 65% to 95%. The notes below explain which form suits which application.
How to choose
Purity Grade
Two grades are available across most of the staphylococcal line. The 95% grade is for quantitative work where the toxin itself is the variable being measured: standard curves, reference material, assay calibration. The 65% grade is partially purified and costs less, which suits qualitative screening, antibody production and method development where absolute concentration is not the readout.
If the result is a number you will report, use 95%. If the result is a yes or no, 65% is usually sufficient.
Native or recombinant
Native preparations are purified from culture supernatant and carry the post-translational profile of the organism. Recombinant preparations are expressed in a heterologous host, which gives tighter lot-to-lot consistency and avoids co-purifying trace material from the native source.
Choose native when you need the molecule as the organism makes it, such as antibody work intended to recognize field isolates. Choose recombinant when consistency across lots matters more than provenance.
Endotoxin-reduced
Bacterial preparations carry residual endotoxin, which activates innate immune pathways independently of the toxin under study. In cell-based assays and anything involving immune readouts, that background can be mistaken for toxin activity.
Endotoxin-reduced material is processed to lower that background. It matters for cell culture and in vivo work, and it is usually unnecessary for direct binding assays and analytical chemistry.
Conjugated and modified forms
Biotinylated preparations carry a biotin label for streptavidin-based detection, used where the toxin is the detection reagent rather than the analyte. Toxoids are chemically inactivated: they keep the immunogenic structure without the biological activity, which makes them the right choice for immunization and for positive controls in settings where handling active toxin is not practical.
Quantity
Most products are stocked in 100ug and 1mg, with available sizes listed on each product page. Larger quantities are produced to order, so lead time depends on production scheduling. Size is selected when you request a quote.