The cell wall components of gram-negative bacteria, such as E. coli and Pseudomonads, are designated as endotoxins. They have a hydrophilic polysaccharide and a lipophilic lipid component and, unlike the bacteria from which they originate, are highly heat and pH-stable. Endotoxins are pyrogens (i.e., they can cause fever if they come in contact with mucous membranes or enter the bloodstream). According to the prevalent
pharmacopeias, the defined limit values for endotoxin content may not be exceeded during the manufacturing process of pharmaceuticals. In mammalian cell cultures that are used to produce biopharmaceuticals, such as immunoglobulins, the presence of endotoxins can lead to cell death. For this reason, ultrapure media (i.e., ultrapure water, with levels proven to be below the limits) must be used to manufacture biopharmaceuticals or to propagate cell lines or cell cultures. The objective of this study is to demonstrate that the ultrapure water produced by the arium pro VF system exhibits an endotoxin content that is far below the prescribed limits and that can be used for the applications mentioned above.
Tag: <span>ultrapure water</span>
Inductively coupled plasma mass spectrometry (ICP-MS) is a highly sophisticated multi-element analytical technique that is increasingly being used for trace analysis in various industries including analytical laboratories. The ICP-MS technique is capable of analysis down to sub parts-per-trillion (ppt) detection limits whereby the lowest detection limits can be achieved only in a cleanroom environment. Because water is used early in tests for trace elemental analysis with ICP-MS, it is obvious that any contamination from the water can compromise an entire analysis. Therefore, the water used must be of a high analytical grade quality (e.g., ASTM Type I water). The objective of the analytical test series described below is to ensure that the ultrapure water generated by the arium pro UV water system has a high purity level (in this case, free of all nondetectable metal elements) and can be used without any problems for trace analysis of elements performed with ICP-MS devices…
In situ hybridization (ISH) for localization of DNA/RNA hybrids in cytological preparations was first described in 1969 by Gall and Pardue. This method enables mRNA transcripts to be detected in tissue sections. Unlike expression analyses based on polymerase chain reactions, the exact localization of the target transcripts can be identified within the tissue…
Plants must be capable of responding to climatic fluctuations, diurnal rhythms, available supplies of water and nutrients, and insect attacks and infestations. To ensure such responses, plants need a network of regulating substances called phytohormones. These substances enable plants to respond to both biotic and abiotic stresses by initiating a cascade of orchestrated actions, and to trigger development-specific processes. In this article, we will discuss a highly sensitive analytical method for quantitative determination of phytohormones. The main representatives of the plant hormones are jasmonic acid (JA), cytokines, auxins, abscisic acid, salicylic acid, gibberellins, and strigolactones.