Simple and inexpensive quantification of ammonia in whole blood.

ABSTRACT: Quantification of ammonia in whole blood has applications in the diagnosis and management of many hepatic diseases, including cirrhosis and rare urea cycle disorders, amounting to more than 5 million patients in the United States. Current techniques for ammonia measurement suffer from limited range, poor resolution, false positives or large, complex sensor set-ups. Here we demonstrate a technique utilizing inexpensive reagents and simple methods for quantifying ammonia in 100 ?L of whole blood. The sensor comprises a modified form of the indophenol reaction, which resists sources of destructive interference in blood, in conjunction with a cation-exchange membrane. The presented sensing scheme is selective against other amine containing molecules such as amino acids and has a shelf life of at least 50 days. Additionally, the resulting system has high sensitivity and allows for the accurate reliable quantification of ammonia in whole human blood samples at a minimum range of 25 to 500 ?M, which is clinically for rare hyperammonemic disorders and liver disease. Furthermore, concentrations of 50 and 100 ?M ammonia could be reliably discerned with p = 0.0001.

SUBMITTER: Ayyub OB 

PROVIDER: S-EPMC4462127 | biostudies-literature | 2015 Jun-Jul

REPOSITORIES: biostudies-literature