The Importance of Using the Brand PYROSTAR™ in Research with Pharmaceuticals

PYROSTAR for Research with PharmaceuticalsThe brand PYROSTAR™ of the company "Wako" specialises in reagents for the detection of bacterial endotoxins. Bacterial endotoxins, originating from the cell walls of the Gram-negative bacteria, are one of the main and most powerful sources of contamination in pharmaceuticals.

What are known as bacterial endotoxins are Lipopolysaccharides (LPS) that form part of the external membrane of Gram-negative bacteria. These lipopolysaccharides have a toxic effect in mammals, producing episodes of fever and septic shock that could result in death. Therefore, the pharmaceutical industry demands methods for the control of endotoxins in finished products and in all the reagents and supplies used in medicine production which guarantee that these products and supplies do not contain endotoxins at dangerous levels. Similarly, research with pharmaceuticals necessitates this control in products before carrying out clinical and pre-clinical tests. As the LAL method is the recommended one by the pharmaceutical authorities for determining endotoxins, this test is the one used by researchers. With the goal of providing pharmaceutical companies and other biomedical branches with reagents and accessories with which the LAL test can be conducted, Wako has launched the brand PYROSTAR™.

VIEW ALSO: Applications of the LAL test in the pharmaceutical industry

One of the most important accessories of the brand PYROSTAR is the Toxinometer®, a photometric instrument designed especially to measure the change in the turbidity that is produced upon mixing a sample which may contain endotoxins when mixed with the reagents of the Limulus test. The name of the "Limulus" test comes from the fact that this test is conducted with an amebocyte lysate from the hemolymph of the Limulus Polyphemus crab, which is why it is known as the Limulus test or the LAL test by the initials of the English name Limulus amebocyte lysate.

Among the other products which the brand PYROSTAR™ uses, we encounter the tests that measure the presence of endotoxins by different methods of detection that have been developed over the years. The tests for the determination of endotoxins are the ones that are described below:

  • Limulus PS Single Test: Is another one of the reagents of the brand PYROSTAR and consists of a single endotoxin test, where the endotoxins are absorbed in a resin called Pyrosep™, designed to this end, and then they are measured using the Toxinometer of Wako. The importance of this test is that the sample can be dissolved in organic solvents so that it is absorbed into the resin. Therefore, the test can be used for samples that are not soluble in water, such as liposoluble vitamins.
  • Similarly, the Pyrostar™ ES-F Single Test Vial is a vial with which a single test of endotoxin determination can be conducted. However, you can also buy the product that contains 100 tests (Kit of 100 PYROSTAR™ ES-F). You can get this kit including the standard endotoxin or not, or in vial form which contains the reagents that are necessary to conduct 4 tests. With these tests, the detection can be conducted via the gel-clot (or gel formation) method, which would be a qualitative or quantitative measurement by the kinetic turbidimetric method.

Carboxymethylated curdlan is added in these Limulus tests to eliminate the interference that is produced by β-1,3-glucans in the test. Compounds that are of the type of β-1,3-glucans also form part of the cell wall of the bacteria and are capable of activating another chain of reactions that are different from those activated by lipopolysaccharides. However, they separate out the proteins which form a gel that is indistinguishable from the characteristic gel of the LAL test.

Curdlan is a β-1,3-glucan and if it is added in excess, it makes other glucans, which may be found in the samples, not interfere with the measurements. In the past, in order to add the carboximetilated curdlan to the reagents of the LAL test, the carboximetilated curdlan used to be mixed as a buffer. However, nowadays, it has been achieved to lyophilise it together with the rest of the reagents. Therefore, for instance, a reagent specific for endotoxins is already obtained for the LAL test by reconstructing the reagent contained in the PYROSTAR™ ES-F vials with water for the lysate test (LAL Reagent Water).

The other reagents you can find in the catalogue of the brand PYROSTAR™ which are useful for the detection of endotoxins in the research of medicines are listed below:

  • Extractor solution for endotoxins to conduct the LAL tests (Endotoxin Extracting Solution for LAL Test), which contains human serum albumin and makes it possible to conduct the extractions of the samples, which will be analysed with greater reliability than if they were being analysed with the use of water or a saline solution.
  • Standard control endotoxin (Control Standard Endotoxin), which contains 500ng of lyophilised and purified endotoxin from the strain of E. Coli UKT-B sy, which serves as a pattern for endotoxin tests.
  • Tubes, tips for Micropipettes and aluminium lids for the tubes of the BioClean® series (BioClean® Series), all of which are with the necessary purity levels to work in environments that are free of endotoxins, where the LAL test takes place, and to conduct the measurements with the toxinometer.


Kit of 4 PYROSTAR™ ES-F (2 ML) with CSE Kit of 100 PYROSTAR™ ES-F (5.2 ML) without CSE
Kit of 4 PYROSTAR™ ES-F (2 ML) with CSE Kit of 100 PYROSTAR™ ES-F (5.2 ML) without CSE