Ethylenediaminetetraacetic acid chemical structure

Numerous positive delayed skin tests in patients with contrast medium-induced non-immediate skin reactions have been reported when the patients were tested with the culprit contrast medium [summarized in 1]. In a large European multicenter study, 37% of patients with non-immediate reactions were positive in delayed IDEs and/or patch tests [13]. The majority of the patients also reacted to the culprit contrast medium and also to other, structurally similar RCM. Notably, in more than 30% of those skin test-positive patients a RCM had been administered for the first time. Thus, there is a lack of a sensitization phase. Again it may be hypothesized that these previously non-exposed patients may have already been sensitized. Different patterns of RCM cross-reactivity indicate that several chemical entities could be involved. No positive skin tests have been obtained with other contrast medium excipients, such as ethylenediaminetetraacetic acid (EDTA), and only rarely patients have been found to react to inorganic iodide. 

Figure 3.6 shows 12 structures that may correspond to the abbreviation DPA. Six of them can be output by the ACD/Name to Structure software package, and six more were found by browsing the Internet. Note that even a specific context cannot guarantee an exact meaning. For example, both structures 3 and 8 were found in publications about coordination compounds. In general, chemical abbreviations are not unique and can rarely be distinguished from other trivial names except for the rather weak criterion that all letters are capitalized. We can conclude that conversion of any trivial name shorter than about five or six characters is not safe. A few rarer exceptions do exist, but this is a very short list. Examples include reserved abbreviations such as those for dimethyl sulfoxide (DMSO) and ethylenediaminetetraacetic acid, EDTA. 

The formulations of the lipiodol W/O/W emulsion developed by us and the conventional emulsions for TAB (Nakamura et al., 1989) are shown in Table 11.6, together with their physical properties. All the materials used are injectable. The anticancer agent used was Farmorubicin (FARM), which is a powder mixture of eptrubicin hydrochloride (BPI) and lactose. The aqueous contrast medium used was Omnipaque 240 , which is an aqueous solution of 517.7mg/ ml iohexol, 0.1 mg/ml ethylenediaminetetraacetic acid disodium calcium, and 1.21 mg/ml tris(hydroxymethyl)aminomethane. The chemical structures of BPI... 

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