A simple method to determine urea concentration using intact Helicobacter pylori and BromoCresol Purple as a pH indicator

Yuh Ling Lin, Chien Tsu Chen, Su Cheng Lin, Cheng Lee, Hsien Shou Kuo, Chun Mean Shih, Yuan-Hsun Hsu, Yi Ping Chin, Err Cheng Chan

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5 Citations (Scopus)


A modified method for urea quantification, by measuring the ammonia formed by urease, used the urease-positive Helicobacter pylori in place of purified urease with a pH indicator dye, BromoCresol Purple, to provide a color change. The color formed was stable for 20 min and could be read at 588 nm for urea quantification. Using this method, urea standard curves were linear up to 8.3 mM. As there was no need for centrifugation or precipitation, the assay was developed for use with 96-well microplates.

Original languageEnglish
Pages (from-to)1077-1079
Number of pages3
JournalBiotechnology Letters
Issue number13
Publication statusPublished - 2000



  • Ammonia
  • BromoCresol Purple
  • Helicobacter pylori
  • Urea
  • Urease

ASJC Scopus subject areas

  • Biotechnology
  • Bioengineering
  • Applied Microbiology and Biotechnology
  • Microbiology

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