Required Suspension of Do Not Resuscitate and/or Do Not Intubate Orders in Interventional Radiology: A Survey of Prevalence and Practices

A simple and reliable method for creatinine quantitation was developed for urine-based diagnosis as creatinine is an internal standard molecule for the calibration of fluctuating urinary concentration. Herein, the quantitation of creatinine in artificial urine was performed in the range of 1-30 mM, covering the normal concentration of human urine, using 3,5-dinitrobenzoate (3,5-DNB) as an electrochemical probe molecule. The chemical interference from various urinary species, including urea, uric acid, ammonia, ascorbic acid, alcohol, albumin, bilirubin, acetaminophen, and glucose, is confirmed to be significantly suppressed when the reaction of creatinine and 3,5-DNB is limited to 5 min with an increased OH- concentration. Additionally, the reliability of this method is confirmed for the use of real human urine samples by comparing the data obtained from this and with that of the conventional method.

Automated summary

A simple and reliable method for quantitating creatinine in urine-based diagnosis was developed using 3,5-dinitrobenzoate as an electrochemical probe molecule. The method covered the normal concentration range of human urine and effectively suppressed chemical interference from various urinary species. The reliability of this method was confirmed by comparing data obtained from real human urine samples with that of the conventional method.