title: Contamination of 0.2-micrometer infusion filters by N,N-dimethylacrylamide.
abstract: OBJECTIVE
  Infusion filters, 0.2 mum, are commonly used in intensive care units as in-line filters to minimize particle and microbiological burden on patients. These filters usually contain either a positively charged or an uncharged membrane. The aim of the present study was to identify and to quantify an additive causing an unexpected maximum at 234.5 nm in the ultraviolet spectrum of a filtered drug solution using a filter.
  
  
  METHODS
  For identification and quantification of the substance, water for injection was used as eluent. Measurements were done by mass spectrometry and ultraviolet spectroscopy.
  
  
  RESULTS
  The unexpected additive in the filter was found to be N,N-dimethylacrylamide. The eluate of 2 filter batches had a mean N,N-dimethylacrylamide concentration of 3.9 and 2.5 microg/mL, respectively. Further investigations showed that after infusion breaks of different duration, the N,N-dimethylacrylamide concentration at the beginning of the next infusion cycle reaches a higher level than that at the end of the preceding infusion cycle.
  
  
  CONCLUSIONS
  The type of filter examined in this study is primarily used in premature infants, newborns, and infants. These patients are vulnerable to neurotoxic substances having a long-term effect. Therefore, N,N-dimethylacrylamide should be completely removed from the final filter product.
authors.affiliation: Klinik-Apotheke, Universitätsklinikum Carl Gustav Carus der Technischen Universität Dresden, 01307 Dresden, Germany. joanna@hw-arts.de
authors.forename: Joanna
authors.initials: J
authors.lastname: Gasch
authors.forename: Reinhard
authors.initials: R
authors.lastname: Oertel
authors.forename: Claudia S
authors.initials: CS
authors.lastname: Leopold
authors.forename: Holger
authors.initials: H
authors.lastname: Knoth
mesh_terms: D000178:Acrylamides / Q000032:analysis*; D004077:Digoxin; D004866:Equipment Contamination; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D007362:Intensive Care Units; D013058:Mass Spectrometry; D008567:Membranes, Artificial; D010316:Particle Size; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000178:Acrylamides; D008567:Membranes, Artificial; D004077:Digoxin; C099046:N,N-dimethylacrylamide